m@Robertson

Larry vs Harry Bullitt Hill Hauler, Back-to-Front Part 3

In this installment we’ll spend all of our time looking at the battery box and the separate controller/charger box that are both hiding under the cargo floor.

Bullit II Build Series
Part 1
Part 2
Part 3 (you are here)
Part 4

This Is The Big One…

Crawling thru the bike starting from the back of the rear rack, we’ve worked our way forward to the cargo box area. This is where all the real work – and all the ‘oops’ and ‘uh-oh’ – happened. I will mostly skip the wrong turns and instead focus on what worked.

Because so much went into doing the basement, and it was a primary objective in this build, this post will be focused there and be talking about just the floor, and boxes underneath it.

The Main Bullitt v2.0 Objective?

Hide the damn battery box. Thats it in one sentence. Lets look at what we did last time. Here is the v1.0 battery box on the Lizzard King.

I say “in case you miss it” above only half kidding. A lot of people do miss it. Maybe they see it and mistake it for a deeper cargo area. It isn’t. It is beneath the floor, hangs under the frame and holds a heavily padded, large battery.

People often make the mistake of thinking it will scrape the ground. It doesn’t. In fact its never touched anything in more than two years of service. But… the bike would look cleaner without it.

Here is what it looked like inside a couple of years ago when I bolted it shut for the last time.

Figure 2: If you want to see more on this bike, with all the details of the battery and whatnot, the whole build process was documented here.

Worth noting:  Before I did that final bolting-up, I had already checked after a few months of wet and dry riding.  No water or crud was making it inside.

Lets skip to the end and see the result:

The battery box is there, but this time you can’t see it. In fact, it holds an even bigger capacity battery this time (it is physically smaller. We’ll get to that later).

There isn’t just one box. There are two. The one in the back holds the battery. The one in the front holds the front motor controller and a weatherproof onboard charger. I plug the bike straight into mains power.

It came out great. It was a bitch getting it there, and I didn’t know if my underlying idea would work until well into the project. If I ever do a Verson 3.0, it will be a by-the-numbers assembly. But I plan this bike to last my lifetime and have no desire to try again. You, on the other hand, are free to do your own and not make my mistakes. So lets begin.

The Box(es)

Lacking machinery, materials and fabrication skills up to this task, I took a tape measure, did some measuring on the Lizzard King (my new frame was still in transit) and started some research. Then I got on the internet looking for made-to-order, simple metal work. I found metalscut4u.com after some googling. They had an online project configurator. I ended up using it to quickly draw up what I needed and placed a work order.

Are they the best choice (especially versus a local machine shop)? I don’t know, but they were the best option I could find, even if the project was a bit pricey. They shipped promptly and the product was exactly to my measurements.

I didn’t order actual boxes. Instead I used what are described as ‘hat channels’: a single sheet of aluminum, with 90-degree bends in a sort of inverted hat shape that is open on two sides. It was a simpler and cheaper job. My thinking was some special needs to fit the Bullitt frame would make it easier to adapt a hat channel into a quasi-box, with extra-thin, short sides I’d put in myself.

Sizing

Figure 4: Length and width as-received. The creepy selfie at left is a bonus.

Since the shop and I are both in the USA, the order process used Imperialist measurements. The hats are 8″ x 15″, with the hat ‘brim’ – the wings that support the box hanging on the frame – at 1″. These measurements are internal, and this matters because the alloy is 1/8″ thick, so outer dimensions are a bit wider as a result. Its the outer dimensions that decide whether the box fits inside the frame.

How deep are they? Its been so long since I did the actual work (8 months as I write this), I don’t quite remember. Roughly 3.5 inches? Don’t pay attention to that as you will need to measure your own battery, and figure out what a second measurement will be in the following next step. Those two taken together, and factoring in your steering arm placement, will decide box depth.

With all the talk about inside and outside measurements, lets touch on the box thickness. On the Lizzard King, that box was purchased as-is, and it uses alloy that is probably 1/16″ thick. Its thin, lightweight and sturdy enough, but not enough to be confident of it withstanding impacts. Thankfully it never has hit anything.

Since I was using a 3rd party metal working service, I had to take what I could get in terms of the thinnest alloy they offered, which was 1/8″. That is twice as thick, and twice as heavy. But its alloy so not that much weight, really. The thick walls make for a lot of strength. Having boxes with both thick and thin material, I’m a lot happier with the thick stuff.

Put The Sides On

I already had a long strip of 2″ aluminum, 90-degree angle bar stock in very thin 1/16″ size (sorry again for the units but to be precise I’m describing it exactly as-sold). I also had a good supply of Shoe Goo, which is a super-strong adhesive that permanently, totally bonds almost anything to almost anything else.

The idea was to cut a precise strip that covers the outside width of the hat. Glue it to the hat both from the underside, and along the vertical edge, which has 1/8″ inch of full edge contact, plus a bead running up along the inside vertical edge. This forms a bond that may as well be welded on.

Attaching the angle stock with glue from the outside preserves the unbroken box surface, and leaves the inside perfectly smooth. It can’t leak if there aren’t any holes. There are no wear points to rub on, like a bolt head or rivet, if there aren’t any. Plus… every millimeter counts when it comes to vertical space. Bolt/rivet-free attachment from the outside reduces internal vertical space by exactly zero.

Figure 5: The rear-most box. I used too much adhesive on the right piece. Not an issue. I goofed and primer’d the hat too soon. That had to be done over after the couple of weeks it took for the adhesive to fully cure.

If you enlarge Figure 5, you can see the underside portion of the side pieces are filed shorter. This keeps them from extending past the curved, bent bottom: No edge to catch on.

Figure 6: Quickee test fit with the sides on the rear hat – now its a box. The shorter height of the sides allow cable egress/ingress.

So much for the back box. The front one is more complicated: The Bullitt has mounts for the side panels in that forward space. You can’t just drop a box into it. This is a big part of why I used ‘hats’ instead of boxes: The need to hand-fit this part. Figure 8 below shows the job fully done.

To clear the side panel mounts, I marked the hat with circles matching the position and outside diameter of the side panel fittings. Next I took an angle grinder and sliced into the marked area in a very rough arc marked on the hat, taking off (hacking) material close to but not crossing the marked line.

From there, the arc was smoothed by hand with half-round metal files. After a fair amount of filing, test fitting and filing some more, I had enough material removed to fit snugly into the frame.

Figure 7: Those pesky round side panel mounts. And a drilled spacer (at bottom)

In Figure 7 above, note the box is shorter than the frame width, and is pushed all the way to the left. The idea was to use that gap for running cables in what will eventually become a deep channel.

After the holes were complete, the next step was to cut shorter side plates that accommodate the side panel mounts. It was important to give the adhesive plenty of time to fully cure, so that was a couple more weeks of down time. Figure 8 below shows the boxes ready for primer.

Primer and paint

Figure 8: Not so sloppy this time with the adhesive. Holes match the Bullitt’s crossbars and will be enlarged later

The next step was to primer both now-completed pieces. Both were roughed up considerably with a random orbital power sander for better primer adhesion.

Figure 9: Primer coat complete. Its thick enough that the box surfaces are now smooth

I spent some time deciding whether to paint the boxes gloss white to match the frame, or a stealthy black. The latter won out and, after a week or so to let the primer cure, I rattle-canned on a couple of coats of satin black automobile engine paint

Other Parts Of The Equation

Referring back to Figure 2, you can see the Lizzard King’s 32ah battery was so big it would have never fit between the frame crossbars. It had to be slung underneath. That was battery cell reality in 2021. Further, because of the Bullitt’s steering arm, the underslung box could not be very wide to let the arm move while steering the bike. Thus you see a battery mounted lengthwise, on a narrower box whose drive-side edge is diagonal and not squared.

This version has to be shallow to fit above the steering arm. That lets you use the full width of the frame space. But it creates a box not deep enough to fit a battery under the floor.

Unless you raise the floor. Thats the key idea – and its not just my own. I’ve since seen other Bullitts where the same thing is done.

The Bullitt’s factory honeycomb floor sits below the top of the frame rails. So we can raise it higher. That increases the effective depth of the box. But the honeycomb floor is quite thick. Millimeters count. The dibond floor sold by Velution is very thin, strong and lightweight so I used that and gained more space.

How Do We Raise The Floor?

That is a fiddly little job to get right. The box lips themselves will raise things up 1/8 of an inch. But where the two overlap between them, its double that height. To even out the rise on all three crossbars, I used a 1/8″ drilled alloy strip. You can see one at the bottom of Figure 7. One goes on the front and the other on the back.

But thats still not enough for the floor to clear the battery. Wood strips cut, drilled and treated against weather were the lightweight answer. I used Home Depot to source those.

Is It Going To Fit?

Before I got to painting the box or affixing the sides to the hats, I had to do a test fit to prove the concept. I dropped in the hats, plunked in the battery, taped on the spacers and…

Figure 10: It fits! (mostly). Dang this is going to work.

It Fits. Now What?

After the test fit, knowing it was very close out of the gate, it was time to do it for real. That involved a whole lot more effort.

Cable management

This is a task a good builder never takes lightly, and can be a nightmare on a 2wd system. Mix in the length of cable runs required by a Bullitt frame and it was a lot of tedious work. I bought a stack of HIGO cable extensions in advance, ordering double what I needed. It turned out I used all of them.

Insulation

To prevent water/sand ingress I used two different types of automobile door insulation – the big rubber seals that run around the edges of car doors. It clamps itself to the tops of the box sides.

Figure 11: At left is the charger AC cord exit. At right, the wood strips, seen treated with an ugly water repellant wood stain. The one on the right is chewed up and only used for testing during the build.

In Figure 11 above, the power input cord for the charger had to exit on the non drive side. I used slit silicone hose to cover the bare (filed smooth) edges of aluminum the cable contacts. You can also see the car door insulation sealing the top of the side edge.

Final Bits and Pieces

Also seen above, the charger is already bolted on. The controller is about to be as well. It and the charger’s undersides were lined with thermal transfer tape, to enhance heat transfer to the thick aluminum box.

You can see in Figures 11 and 12 how the slightly-shorter wood slats, and the offset to one side, creates a channel for cable runs.

Figure 12: Final fitment is complete. Next step is to bolt the floor down. The bolts in the left-most shortie wood slats will be used to bolt the floor down when it goes on.

You’ll have to scroll all the way down this page and look closely to even see this one: The boxes are not level to one another. The forward box (which doesn’t need as much depth) is sitting on top of its 1/8″ alloy spacer strip, and on top of the ear of the rear box. So it sits higher. The rearmost box needs every bit of space it can get, so it sits directly on the frame crossbars.

Battery Fitment

The battery is fixed in place with small bits of super-dense closed cell MinicelT-600 foam.

The battery fits so snugly in the available space that cable routing was difficult. The charger cable was split to two lines – one forward to the charger, another rearward to the top tube bag for an aux charger if needed (like a Cycle Satiator doing an occasional precise balance charge). Battery output also had to be split to each motor, front and rear.

The Wood Spacers

These were bolted directly to the frame, and further clamped by bolting the floor on top of them. Not in the pictures: I used a layer of hard rubber adhesive stripping, 1″ wide, atop the wooden slats. That provided the final bit of extra space to let the floor lay flat without bending it over top of the battery pack.

The short wood spacers at left in Figure 12 are sitting on a layer of that rubber adhesive, with more adhesive squares on top sides for proper leveling. You can also see big, loose zip ties that have not been trimmed yet. Those are cable guide loops for wires – insulated in silicone tubing – that run underneath the floor.

Lastly

The front box does have two open holes thanks to the frame’s side panel mounts. The charger and front motor controller are both IP65 rated and can only benefit from some ventilation, so this is not an issue.

The Floor Goes On

I planned from the beginning to use extra clamping to the floor. I don’t want to see a giant battery bounce into sight. I added four additional bolts. The foam pads on the Velution floor that cover all frame contact points are already cut to match the frame holes. So I knew where to drill without having to measure.

Figure 13: The floor is on, and staying on. I lined the edges of the floor board with rubber channel liner.

The floor has countersunk holes pre-drilled into it. I wanted to spread out the clamping force, so I used some extra-wide countersunk washers from MacMaster-Carr. I also needed two sizes of extra-long countersunk M6 bolts from the same source.

The Floor Attachment Tweak

I expected that raising the floor had one consequence: The holes would all line up, EXCEPT the two on the forward bulkhead, behind the front wheel. Those would be up high and no longer match the frame crossbar holes.

When I was thinking this issue through, I didn’t yet understand how simple it is to drill thru dibond floor material. What I should have done is just drill two new holes, and plug the factory originals. By the time I realized this, I had already bolted the floor on. To undo that I would have to take it off again. The gymnastics needed to get bolts, washers and nylock nuts together in between those two boxes… No thanks. So I stuck with the original plan.

My first solution involved making two patch plates for a second bolt to fit through the original floor hole (the bottom bolt and patch plate are tightened on before the floor is bolted down).

Figure 14: the patch plates, without backing sleeves/washers. Click to embiggen

A few days later, I realized a spacer block from Velution that I hadn’t used made a nicer substitute for the patch plates.

Figure 15: Neat little brackets. Ugly-ass washer stack

In this picture I just fit the spacer blocks with a stack of washers. Once fit, I measured the space and replaced that stack o’ washers with a single black alloy spacer that bridges the gap precisely and cleanly.

Failed/Discarded Ideas

Plug in the charger via an External panel plug

I bought and still have the C14-type panel-mount plug for this. I’ve seen other Bullitt battery boxes do this, but they are not hidden between the frame rails, so they plug in on the right or left side.

Since my box sides are hidden, I could only put the plug in the back. So I have to get down on my knees every time to plug in the charger. Screw that. Plus I did not want to cut holes in the boxes. You need a hole to have a leak.

Figure 16: I just ran the power cord back to the frame bag. There is about a meter of extra cord, plus I keep a 15-ft (4.6 meter) flat appliance cord in the bag in case I need to reach out further

Interconnect the boxes with a tunnel to pass wiring between them

The sheer size of the battery eliminated this idea. I had a plan… but then the battery arrived. And the hats arrived. And I saw there was no way anything would fit unless it was just a pair of gasketed open holes. Nope.

Make a 1-piece double-hat box instead of lumping two next to each other

This didn’t happen for one reason: Money. This would take the project out of the realm of a cookie-cutter web site configurator’d project and make it a custom-consultation job. Someone with better fabrication resources or abilities will want to do it this way but it was a bridge too far for me.

Make cuts in the box ears that interleave the two sitting together

Neat-o idea. Sounded great sitting and thinking about it. Then I got into the actual build and had 40 things to do, and this was a great big #41. In the end simply adding two alloy strips of an equal 1/8″ thickness on the front and back dealt with the issue just fine.

Qapla’

Figure 999: If you want to see a battery box, get your face down to ground level.

We’ll talk about the custom battery, the onboard charger, the cargo box liner, the front wheel and a few other bits in Part 4 to wrap discussion of this bike up.

Larry vs Harry Bullitt Hill Hauler, Back-to-Front Part 2

This continues the walk-through of my hill-climber Bullitt, starting with the mid drive motor installation and taking a close look at its BBSHD configuration.

Bullit II Build Series
Part 1
Part 2 (you are here)
Part 3
Part 4

So lets continue…

I’ll jump straight into the physical motor installation.

Mounting The BBSHD To The Frame

The install on this motor was almost exactly as I have already described for the Lizzard King. Its the same bike frame, after all. There were, however, some minor differences.

frame fitment was different

This frame just flat out did not want the BBSHD to fit. The cable boss under the bottom bracket was not quite in the same spot perhaps. Or dimensions on the frame were subtly different somehow. Either way, that cable boss blocked the motor. The proper solution to fixing this on this frame would have been to go to the motor and file back the forward bolt mounting ‘ear’ until the motor fits. Restated: sacrifice the mounting plate’s forward attachment point. Then give yourself the exact same motor attachment method that Bafang themselves use for the M625 – the upgrade to the BBSHD. It doesn’t have a forward bolt position either. What does it have? They do the Hose Clamp Trick (although not as well).

Above: What the Hose Clamp Trick looks like on a Bullitt if you glance down. Its been awhile since I built the bike so its a little grimy. 5 minutes with a toothbrush and some detergent would clean it right up.

This link goes straight to the motor clamping section of How To Build An Ebike From Scratch. While the description of the motor mounting and that Hose Clamp Trick is not on a Bullitt, the background info given, plus the detailed description of how to lock a BBSHD down permanently, so it can never shift whether it wants to or not, makes using that link and companion article the best way to describe what I did.

Based on other owner reports that came thru when I was building mine, there is variance from frame to frame that can yield an easier fitment, or a harder one. Naturally I got the harder one.

Shorter Crankarms

My Lizzard King used forged 175mm (Shimano Steps) crankarms. I had a spare set of the same arms on a shelf, in 170mm length. So I just used those. If I had to buy a set of crankarms, I would have tried to get hold of some 165’s.

Wire Tunnel

Once again I used a length of PVC for a protective wire tunnel on the top of the frame to run motor wiring forward. I used white furniture-grade PVC. Furniture grade PVC is more expensive than standard white Schedule 40 from the hardware store. But its shiny, pretty and a perfect match to the Milk Plus color and gloss finish.

The tube is held on with two industrial, giant-sized white zip ties. They’re overkill but don’t have that ‘zip tie’ look, because they are so physically large. The PVC is sitting on a bed of adhesive white foam to help hold it in place as bumps and bruises accumulate over time..

And that was it. Everything else was a carbon copy of the Lizzard King motor install.

The original Box Two 9s drivetrain, on a new and shiny fresh bike build. It will never be this clean again. The pedals are Funn Rippers with spring-loaded cleat engagement and yes, I do ride cleated in.

Motor Configuration (BBSHD Settings)

The BBSHD settings differences are not many versus my flat-land Bullitt, but the differences in performance are profound. On the Lizzard King, BBSHD pedal assist on level 9 – the maximum – peaks at a sustained 400-450 watts. That is a considerable power reduction that makes sense on flat land.

But in steep hills where the slope can go from zero to Uh Oh in about 30 feet, you are well-served to take it up a notch. I’ll cover all three screens here, but the changes that matter are almost all on the last one: The Pedal Assist Screen.

The Throttle Screen

This screen is almost my default. The only change is an evolutionary one: Start Current is reduced to 2%, so the throttle rolls on even more gently to the drivetrain. You hear a lot about how Bafang motors bang and jerk on the chain. 2% on Start Current completely smooths out that behavior. Also setting End Voltage to 4.2v creates a smooth throttle curve that makes it easy to modulate power output in very fine increments – the opposite of the default behavior.

The Basic Screen

Once again, this is pretty much my standard settings on this screen. It retains my speed limit graduations, which are meant to help cut power when my cadence gets high. Essentially what I did with the Speed Limit percentages was start at 100% on Level 9, and then work my way back in simple 5% increments down to the bottom Level 1.

The Assist 0 limits of 1 and 1 are there to preserve the normal function of throttle when you set the screen to Level 0, which disables Pedal Assist.  This lets you pedal with no motor support without turning the motor off.  Throttle remains available in case of an unexpected need.

I have strongly reduced the effect of the Speed Limit cutbacks via separate settings on the Pedal Assist screen. Since leaving these alone doesn’t hurt anything, and the fewer changes the better, I left my generic settings in place.

The Pedal Assist Screen

This is where the magic happens. The Hill Climber settings are based on my Surly Big Fat Dummy’s settings, which was my former ride in this area. I took what worked on that single-motor cargo bike, copied them to the Bullitt and then experimented a bit.

Since Bafang does not tell anyone anything about how these settings interact, we have to guess on some things. There is no way to set a specific power output level that is reliably sussed or documented.

The settings on this screen move the maximum steady output of pedal assist power to 900-950 watts. Thats a lot, and enables me to select assist level 6 or 7 and still get up the worst hills, with a safety margin available in 8 or 9. This turned out to be especially handy when I was hauling several 50kg loads of gravel for a landscaping project.

ABOVE RIGHT: the new Hill Climber. LEFT: The flat-land Lizzard King. Only Current Decay and Keep Current are changed. Small differences, big results.

NOTE:
Version 2.2b of the open source BafangConfigTool has a graph that does a decent job of trying to explain how the settings interact and affect performance.

Start Current is very low at 2% for the same reason it is at 2% on the throttle screen: Eliminating jerky initial engagement (5% is what I used to use).

Slow Start Mode is as gentle as is confirmed to be safe for the motor’s controller. Lower numbers here = slower starting and 3 gives me the gentlest motor-safe slope to that curve.

Start Degree Signal is a fairly prompt 4. Once again the problem to beat is starting from a stop at an intersection while on a steep hill. Specifying a lower number of pedal assist signals to accept before the motor kicks in makes it start power delivery sooner, but I have also set Start Current and Slow-Start Mode so low this relatively fast engagement doesn’t cause any concerns with drivetrain strain.

Stop Delay remains as small as is safely possible to preserve the motor controller.

Current Decay (one of only two changed settings) has been set to the maximum of 8, which either minimizes Current Decay, or eliminates it entirely (Bafang isn’t giving anyone any help figuring out which, or when). Having high cadence reduce power assist makes a lot of sense on flat, paved ground, but when you are set in a granny gear and pedaling like mad to crawl your way up an excruciatingly steep hill, the last thing you need is for the motor to cut back power thanks to high cadence. It also looks as if this one setting is primarily responsible for the increase in peak sustained power.

Stop Decay remains at zero. The idea is if you stop pedaling, you want the motor to stop. I ran some experiments recently as part of an internet discussion. I found a suggested setting of a whopping 1100 ms (i.e. set it to 110) produced nothing negative. The cutoff still happened so fast I couldn’t argue it hurt anything. In steep hills, a long setting like 1100ms could actually smooth things out a bit if crawling up a hill and perhaps your cadence stutters accidentally. Not a setting I kept, but its worth noting.

Keep Current (the second of two changed settings) is kicked up just a bit to 40% from the Lizzard King’s 30%. Frankly both settings are aggressive. The Current Decay of 8 is preventing this setting from engaging at all unless I am on flat ground, moving relatively fast (i.e. not crawling at 6 km/h up a hillside) and spinning my crankarms at high cadence.

Version 2.2b of the BafangConfigTool can be downloaded (entirely at your own risk) at the author's web site.  I make no representation of any kind as to its quality, lack thereof, your ability to avoid totally destroying your motor or cause a horrific accident of some kind as a consequence of using it.

Saddle and Seatpost

I used the same Ergon ST Core Prime saddle that I know my butt prefers. However, since the Kinekt post on the other Bullitt has a pogo stick effect at fast cadence, and I know the Thudbuster LT doesn’t: I put the Thud on this time.

That cable is a seat leash to add a few moments delay to a theft attempt. I covered the rear camera in the dashcam series.

Stuff In The Frame ‘Triangle’

I used a Blackburn frame bag just as on Godzilla. However, this one does not hold the front motor controller. It does hold the batteries for the front fork lights and COB LED strips. It also holds the mains power cord for the onboard charger, as well as the charger’s 15-foot/4.5 meter power cord extension. There is also a secondary charger connection to the battery in case I want to plug in an external Satiator charger or similar (we’ll get to the charger stuff in a future installment). Beyond that, there is space for wallet, sunglasses, phone and keys.

The zipper on the other side of this bag holds the power banks for the headlights, side light strips and a dashcam.

At the back of the cargo bulkhead are Velution’s Large bag solution, that uses Ortlieb large dry bags. These are much bigger than the Fahrer bags on Godzilla, and I like the Ortliebs a lot better. They hold all of my routine tools, spare inner tubes, patch kits, pump and so on. Because I need to routinely empty these bags when I go inside of a shop and leave the bike outside, I keep the contents in easily-removed cloth zippered pouches (two each side). That makes it easy to pull out the pouches and toss them into a carry bag.

Steering/Cockpit

For handlebars, this time I chose the Ergotec Space handlebar. Think of it as a Jones Bar in Junior size. Its backsweep is less than the Jones 45 degrees, but still comfortable. I installed short Ergon grips hoping to extend them longer than normal with segments from a Wolf Tooth Fat Paw grip, but I needed so much room to fit the shifter, I couldn’t. I ended up with a normal grip size.

Cockpit Version 1.0: At the shop on the night assembly was completed. Dual independent throttles, dual independent PAS settings … and dual displays. Not subtle.

Everything is in easy reach on the bars and – originally, at least, is a carbon copy of what I had already done on the Lizzard King.

Cockpit Version 2.0

A few months went by, and I decided to clean up the bars at the expense of information display, which I am not a fan of anyway (we got along riding bikes just fine for more than a century without all this data reporting).

Pretty clean handlebars – as far as 2wd bikes go. Also Cockpit v 1.0 had the grips upside-down.

The DM03 Bafang Display

The DM03 is made by VeloFox for Bafang BBSxx motors. It is a small monochrome OLED screen. Sales ads describe it as an improved version of the SW102 display. The SW102 is most commonly known as what the EggRider v2 display/programmer uses. I only wanted an ultra-small, discreet display, not the extra EggRider functionality.

A big selling point of the DM03 was it supported 9 levels of PAS. An SW102 gives only 5. Additionally, the DM03 has larger buttons than the SW102. Since I also have an EggRider v2 on my Cyc X1-powered 29er, I can compare the two displays look-and-feel directly.

Knowing how visible my EggRider was in bright sunlight, I was under no illusions: The DM03 display is only just barely visible in bright sunlight. But I was after compact size, and I can do without a display. This is a perfectly functional PAS control unit for people who do not feel a need for an ever-present data readout.

If its foggy, in the shade or overcast, then the display is easily visible. You can also shade it with your hand and squint at it in the sun, but you’d better not do that while in motion. I only look at the thing to remind myself which PAS level I am in.

The DM03 Advanced Settings Code

Just like other Bafang-compatible displays, the DM03 display for Bafang motors has an Advanced setting, where you can edit things like wheel diameter, and make the all-important selection to support 9 PAS levels. The code to get into the DM03 display’s Advanced Settings screen is1657. I purchased two of them from two different vendors. Neither provided the code with the display, but both promptly gave it to me when I asked so I could finish setting up my bike.

Cockpit Version 3.0

I’ll add a picture when this gets installed. I use a KT controller and display for my front motor. As of the time of this writing, I have a KT LCD4 display on order and en route. Essentially it is a KT-flavored version of the same minimalist DM03 display. This one uses old-school LCD, and has a backlight. It should be perfectly visible in bright sunlight and total darkness. We’ll see. This will take all of the displays off of my handlebars for a cleaner setup.

The KT LCD4 should work MUCH better as an LCD in sunlight versus the similar OLED displays.

Carbon Fiber Steering Tube

I used the Velution one-piece carbon fiber steering tube. I found with the Lizzard King I moved the handlebars once to find my optimal height … and never moved them again. The Velution tube is a small fraction of the weight of the steel factory model plus the weight of the EasyUp is gone. You also get a MUCH cleaner look with the included smooth alloy spacer.

Heads-Up: If buying the Velution steering tube, be aware it does not come with a crown race (not their fault; they never said it did). Source one yourself. I used a steel Cane Creek 40.

Kinekt Suspension Stem

After going to all that trouble to lose weight on the steering tube assembly, I gave some back with this Sherman tank of a bicycle stem. For me it is worth it. My wrists have never been the same after a car hit me in 2017, and between the swept back bars and a suspension stem, this is what I need to be able to ride without pain getting the better of me.

I upgraded the internal spring to the extra-firm Orange version, which is not available unless you buy an orange 1.5″ upper seat spring directly from Kinekt. I also installed the damper upgrade kit. That gives you a stem so firm you can’t move it by hand. It only moves when installed. So I can use it with a full lean-over seating position and it will not bottom out on me.

The Cargo Bay

Here’s where all the work is, and this is where the build actually gets interesting. But given how long this post is at this point, its time to put a sock in it and save that topic for Part 3.

Larry vs Harry Bullitt Hill Hauler, Back-to-Front Part 1

A Bullitt has been my daily driver in all-flat terrain for more than two years. Now I need another for steep hills. Rather than just copy the original I will re-think my choices and make some cool upgrades.

My first Bullitt - the Lizzard King - was the basis for this bike build and written up extensively here.  This bike is essentially a v2.0 of the same bike.  There is much background detail left out of this current discussion (like drama-free AWD) since it was covered the first time around.

Bullit II Build Series
Part 1 (you are here)
Part 2
Part 3
Part 4

Bookends!

Before I get started, lets address why I need two Bullitts. When I built my first one, it was a bucket-list item I expected to last me forever… and its still going strong. But, here’s the thing: I split my time between two locations.

I work in Fresno California, where the land is all table-flat, and my job has for the last several years required me to essentially move there and set up a second residence. My actual home is in Pacific Grove, California… which has totally different terrain. Where Fresno is roasting hot in the summer and flat as a table, ‘PG’ is smack on the Pacific Ocean seashore, is only flat at the shoreline and has plenty of low but steep hills. I live at the top of one, in fact.

Recently I was finally able to start living at home again. My Surly Big Fat Dummy provided cargo bike duties, but I found something I didn’t expect: Having had a frontloader for a couple of years, now I knew what I was missing. I didn’t want to put up with the quirks of a longtail. I ended up describing the differences in detail. I found I was actually resenting the ride limitations, and putting off rides as a result.

Sneaking into Laguna Seca Raceway while it was closed for construction – I had the whole complex to myself. The Surly Big Fat Dummy was a joy to ride that day.

Screw that. Cycling is an integral part of my life. Its time to

Build Another Bullitt

As part of the build planning process, I needed to do a Build Sheet. Click the image below to go to the actual build sheet complete with links to almost every part in the build. I won’t discuss every bit and piece in this short series, but this list contains pretty much every part.

This image links to a Google Docs parts list with live links to the parts

So… how do I organize this writeup? This bike is at its core just an improved version of the one I already built and documented. There’s no point in doing that all over again, but at the same time its hard not to if I want to avoid making the reader bounce back and forth from one build description to another.

Lets just start at the back of the bike and work our way to the front. I’ll go into details where I think they are worthwhile, and be brief when I think I am on well-covered ground.

Rear Rack

This is a fairly common Axiom Streamliner DLX. Its got dropout extensions that move it well back for heel clearance, and a 50 kg weight limit. It is the identical rack I used on my first Bullitt, but oddly, this time the rack fit perfectly with none of the mods needed to get its dropout extension to fit. Apparently Larry Vs Harry have moved the threaded boss on the dropouts down by just a bit versus the ones they sold two years ago.

A standard-issue Axiom Streamliner rack with an extra-beefy front mounting bracket. No idea if this increases its capacity but factory stock its rated for a lot of weight already.

I also used a beefier center stay mount from one of my Axiom Fatliner racks and created a stronger-than-stock solution.

Similar to the ‘bobtail’ deck I made for the Lizzard King, this rack has a ‘deck’ made up of two components. One is a long strip of aluminum flat bar, 2″ wide and 1/16″ thick (sorry for the Imperialist units of measure but thats how its sold here). This flat bar is drilled and bolted to the front of the rack using existing holes. Holes drilled at the rear simply use a zip tie to attach it to the back of the rack. As previously, this thin aluminum bar is part of the rear fender solution.

The Kicktail

You’ll notice the deck bar is longer than the rack, and bent up in the back. I did these two bends by sticking the straight alloy strip in a big steel door and frame, and putting my weight behind it. With that bend in place, mounted on the rack, the deck now has a sort of kicktail… like on a skateboard. It doesn’t serve the same purpose though: The extended bit of deck catches water spray coming up off the tire. So its part of the ‘fender’.

The deck is extended in a second bend that goes up to vertical. In the back of this portion, I stuck some prismatic red tape – the same type as is used in municipal street signs – for a big passive reflector. Additionally, on the front – because why not? – I mounted a square of yellow prismatic tape for forward-ish reflectivity (my local laws prohibit the use of red, facing forward).

Lastly, at the top of the kicktail, you can see a short black strip. This is a narrow length of thick rubber mastic tape. It extends well past the deck’s edge and folds over onto itself, so it becomes an extended rubber bumper. I have learned from doing kicktails like this in the past that if you don’t cover the trailing edge in rubber, sooner or later you cover it in blood (even if you file the edges down).

Last time, it was a ‘bobtail’. Bent differently so it was a smooth curve. Executed a little differently this time to give me a tighter radius bend and a perfectly vertical section this time for the rear reflector.

The Plastic Sheet

The second component to the rack deck is a bit of thin flexible sheet plastic. It has been cut to fully cover the rack, and then slipped under the aluminum bar. Holes matching the top deck have been drilled thru it and as such it is affixed tightly and permanently to the rack. To mount a pannier, you only have to lift up the very thin plastic and attach the pannier’s hooks as usual.

The use of a narrow strip of aluminum, coupled to a flexible sheet of plastic that covers what the alloy does not, gives me full rack deck coverage while maintaining my ability to easily attach a pannier. Why bother? Because this is a part of the rear fender-that-is-not-a-fender coverage.,

Rear Mud Guard

The closest thing to an actual fender is a really big mud guard. It is a Mucky Nutz Fat Face Fender XL (They sell white ones on clearance dirt cheap). It is a front fat bike fender, put on the back wheel, and reversed. Then to extend it in back I added some white gorilla tape. It is bolted to the frame in front using the fender bolt and boss that LvH put there. This bolt pulls the mud guard forward to clear the 2.0″ Schwalbe Marathon Plus Tour tire.

Working together, the rack, rack deck and mud guard provide full fender protection without the use of a fender.

A little matching white extra wide gorilla tape, judiciously applied, extends the mud guard up to the rack deck – no water makes it onto the rider.

Brakes

Same as I do on every one of my bikes: I am using 203mm wide, 2.3mm thick Tektro Type 17 rotors and Magura MT5e 4-piston calipers front and rear. The front brake cutoff is connected to the front motor and the rear cutoff is connected to the mid drive. It is not possible to cross-connect the cutoffs to the dissimilar motor controllers so either one cuts off both motors.

Rear Wheel (and Drivetrain)

The Lizzard King, my original Bullitt, has an 11-speed drivetrain and a 52T (!) front chainring, feeding an 11-42T rear cluster. I only use the middle three or four gears to maintain good chain alignment and high pedaling cadence.

This time I need to negotiate steep hills whose slopes vary, often on the same climb. So a big rear cluster is a given, strength is paramount and I need more usable gears to work with the varying terrain.

The Bullitt has short stays in the back. A BBSHD moves chainline outboard. So no matter what chainline angle will be a challenge. Its going to be tough to use the smallest and biggest cogs on the cassette.

Done… Then Re-Done

Drivetrain Plan A

My first setup was a 9-speed system. I used the Box 2 Extra Wide derailleur, an ebike-friendly Box 1 single-shifter, and its matching Box 2 12-50T cassette cluster. I have used this hardware in the past. It is a premium solution that is not the cheapest, but a lot less expensive than the upper tiers of the other Big S brands.

Pics or it didn’t happen: The Box derailleur can reach the 50T cog. The 12T little one can be reached too. But both of them are too far over inboard or outboard to be used meaningfully..

I labeled the Box Components drivetrain as Plan A. We’ll look at Plan B, and why there is a Plan B, further on.

Next in the drivetrain, there’s the front chainring. I have used the 40T Lekkie chainring and the smaller-than-stock motor cover it requires on my Apostate, and knew it worked well. The 40T ring also has a lot of inboard offset, which you need on the LvH frame.

The Lekkie ‘Pro’ 40T chainring, which only fits over top of the Lekkie motor cover. Note the smaller chainring teeth that are 10-12 speed compatible. No 9s.

But I need as much offset as I can get. Lekkie makes a ‘Pro’ line of chainrings, and they have an additional 2mm of offset. I wanted that extra 2mm as I will ride this bike on the bigger, inner cogs. Complicating things: the Pro rings are not 9-speed compatible. They have a different tooth profile meant for 10-12s systems.

I got around this by using a SRAM EX1 mid drive chain, which is compatible with 8, 9 and 10s systems, so I’m still good.

By using the Pro chainring I gain 2mm. If I perform an optional modification to the Bafang motor casing, I gain another 2mm. With those two mods I moved the chainring a full 4mm inboard towards the seat tube.

Shave off some of the BBSHD motor housing, just behind the Lekkie motor cover. This lets you do without a 2mm spacer to gain that much more offset. Done in about 15 minutes with a hand file.

Drivetrain Plan B

After I built the bike, and ran it for a couple of hundred miles, I was not happy with the Box Components drivetrain. The matched set of components are every bit the butter-smooth, high quality system I expected them to be. However, chainline considerations kept me from using three of the gears on the 9-speed cluster. Since I am a pedaler and not a throttler, I still benefit from lots of gears despite the electric assist. A 6-speed leaves room for improvement. I was missing my 11-speed on my other Bullitt.

Contemplating this, I had – sitting on a shelf unused – a Microshift Advent X 10-speed drivetrain looking for a home. It looked like a solid alternative that might give me a couple more gears, with no meaningful penalties. Here’s a comparison I put together while I decided what to do:

My real comparison was between the top two choices, but I also threw in the Microshift Advent 9-speed steel cluster on the Box 2 derailleur (I use that on my Apostate) just to see how it lined up.

In the chart above, the red cogs are too skewed to use. The yellow are livable if I must and the green are good to go. This chart told me

If I am limiting myself to my 3rd-from-the-top cog to be absolutely safe, both clusters are giving me the same 34-tooth big cog.
The next cogs down on the Advent X give me as-good or better low gearing.
I get more gears to work with – two more – on the Advent X.
I never want to use the smallest cog anyway on any mid drive build, so I don’t care about the little one on either choice.
It looks like the Advent X is going to give me smaller cogs for when the ground is flat.

The saying goes that ‘Steel is real’ when it comes to tough bike frames. The same is also true of a cassette cluster that gets flogged by a mid drive motor.

Here are some known issues that aren’t on the chart:

I’m going up steep hills with 100+ lbs of load on the bike, not counting my own self and my extra heavy locks (2 meters of boron steel noose chain and two motorcycle U locks). This puts severe strain on the drivetrain and demands a conservative limit on how skewed I run the chainline.
The Microshift Advent X cassette is ideal as beefed-up mid-drive-friendly clusters go. It has all steel cogs and is permanently pinned together on all but the smallest cogs, so force is distributed across the entire cassette body rather than having one cog dig in at a time.
My handlebar layout made space a premium. The Box One shifter surprised me: Shifting often required the full throw of the shift lever, so it needed more space on the bars. SRAM shifters only require a very short throw. So there was something else I was missing.

Chainline on the inside, middle and outside. Even though I can get to the 48T cog, chainline is too skewed for a hi torque uphill slog.

with 250 miles on the odometer, I changed the drivetrain for the Advent X. It has worked beautifully. Shifting has been great all across the gear range. When I need a new cluster, I’ll be replacing a US$40 part.

I also followed a tip from a Youtuber and put an 11-speed chain on this 10-speed system. 11s chains have identical inner dimensions to 10s. They are just a hair narrower on the outside. Using an 11s, you gain an absolutely silent drivetrain. I didn’t realize how loud my SRAM chain was until I switched and… blessed, complete silence. It runs as quietly as a belt.

I used a Wipperman Connex 11se ebike chain on sale at JensonUSA for a whopping US$23.94 rather than the usual US$106.95.  After seeing how well it performed, you can bet I bought enough spares at that price to last me for the foreseeable future.

On the innermost cog, which we’ve already established is not usable, the limitations of a mid-length cage versus the Box 2’s extra-long cage are apparent. Its a smaller cog than the Box 50T, but the derailleur is pulled far forward thanks to its lesser ability to wrap chain. Right picture: Three cogs down – the one I consider the max on really steep, loaded climbs – the derailleur is in a happy place.

I still love the Box Components drivetrain. I’ll move the 12-50T cluster to the Apostate, which can use the bigger cogs. The derailleur and shifter… I’ll find a use for them someday.

Build a Wheel

The final drivetrain item is the construction of the rear wheel. I originally wanted to duplicate the Lizzard King’s rear wheel, but the almost-indestructible SunRingle MTX39 rim was unavailable. The DT Swiss FR560 downhill rim is at least as strong, half the weight and twice the price. I’ve used them before and they are awesome so thats where I went. I stuck with my usual DT Swiss 350 Classic ratchet engagement rear hub, with the ebike/tandem 24pt ratchet and steel cassette body upgrades. I’d have preferred a DT 350 Hybrid that includes these upgrades on a beefier hub, but just like the MTX39’s, they were nowhere to be found at the time. Spokes are Sapim Strongs with brass nipples.

The rear wheel is shod with a Schwalbe Marathon Plus Tour, which has a near-knobby articulated tread. Our local bike paths get covered in sand whenever the wind blows, which is a lot here.

This is a paved path about 15 feet wide and the main local urban cycling thoroughfare. It was buried in sand the day before when the wind kicked up. I need knobby tires year-round here.

The next step from the back of the bike forward is mid drive motor installation and (drumroll) configuration. That is a big enough topic to make this a good time to wrap up, take a breather and continue the story in the next post.

DIY Bicycle Front (And Rear) Dash Cam, Part 3

Here is a quick wrapup on DIY, ultra high-resolution bicycle dash cameras. We look at sharing between bikes and issues that go with routine daily use.

This is the conclusion of the topic introduced in Part 1, where started out by looking at the rationale and parts needed for a high-quality DIY front and rear dash camera solution.

Odds and Ends

I originally wrote most of what you see here within the Part 2 Installation and Config post, but for clarity and brevity’s sake its better suited to a short, separate treatment.

There are only a few things you will want to stay on top of when living with your dash cam setup. Lets go over them now.

Long Term Maintenance?

Camera Settings

Every once in a while, the camera will have a brainfart. One morning you will fire it up and it won’t work right. Investigation may lead you to discover it has reset itself to factory defaults. Thankfully, it only takes a couple of minutes to redo them – especially now that you have a guide to use to knock them out quickly.

What I usually see is a message telling me “Memory card is full”. Which should never happen, because the camera is doing loop recording. It is supposed to automatically records over the oldest recording on the Micro SD card. So the card can’t fill up. But it did.

That is a sign that loop recording has shut off. Enable it again and you solve that problem, but if that setting reverted, very likely you will find they all changed. That includes both the video settings changes and the overall system settings. Literally this morning I just had to re-enable all of the video settings, and then also had to go into the system settings and a) redo the date/time formats and b) enable the date/time timestamp… but the camera still remembered the correct system time, so it wasn’t a total loss of memory (still, check the system time just in case) or a full reset.

Riding daily and thus needing two runs per day with the cameras – to the office and back home again – I find this happens about once a month with my older camera models (the one that balked this morning was an older Akaso V50 Elite, which I would not buy again now that the V50x is available). It has not yet happened with one of my V50x’s.

Battery

Over time the battery loses capacity. Not a big surprise as that is normal for a li-ion pack. Hooking up the camera to an external power source is a big help for this. The power source just keeps the li-ion pack inside the camera topped up… almost. It doesn’t replace it.

When the camera starts getting old, you start seeing a situation where even if the camera is connected to an external power supply, it still dies mid-ride. That is because running the camera at this high resolution and frame rate means it eats a tiny little bit more power than the power feed can pump back in. As the battery ages, this slight disparity catches up with the camera.

The solution: every week or two on an old camera I need to turn the camera power on and let the camera sit, turned off, and charge its battery. Then its good again for a couple weeks. This can be done while I am charging the bike so its no big deal. Also, since these cameras come with two batteries, switching them one for the other on occasion puts wear on both of them and staves off this issue for quite some time.

I have never had a battery get so worn I considered replacing the camera. So this is an issue but its not the end of the world.

Sharing Cameras Across Multiple Bikes

I shared a parts list in Part 1 already, but lets do another, slightly different one and look at project cost for one bike, then two.

front + rear cameras for single Bike:

Action Camera    US$90.00 x 2
SD Card             20.00 x 2
Front Camera Mount  18.00
Rear Camera Mount   12.00
27000mah Power Bank 30.00
USB Cables (2 pak)  11.00
-------------------------
Total Cost         291.00
                  =======
Cost Per Bike      291.00

Front + Rear Cameras For Two Bikes:

Action Camera     US$90.00 x 2
SD Card              20.00 x 2
Front Camera Mount   18.00 x 2
Rear Camera Mount    12.00 x 2
27000mah Power Bank  30.00
USB Cables (2 pak)   11.00 x 2
Extra Scuba Box      13.00 x 2
--------------------------
Total Cost          358.00
                   =======
Cost Per Bike       179.00

What we’re doing above is buying two of everything to mount the cameras, but just one power bank and one set of cameras.

To move from one bike to another we just pop the cameras and power bank off of the one bike (remember the scuba boxes make for quick-detach) and right back onto the second bike in literally just a few seconds.

US$291 sounds like a lot until you look at your alternatives. Tally up the features you won’t have when buying a commercial bespoke solution, versus this one. We went over the alternatives in detail in Part 1. If you add to it the fact that it is easily made portable, works for two bikes and gets your costs down to US$179 per bike… you are way ahead of the game.

Extrapolate this out to as many bikes as you please. For three bikes, you come up with a total of US$425, which yields a per-bike cost of to US$142.

Video Editing Software

Recording your travels, you might want to look them over (or maybe you had an accident and need to show it to the cops or your lawyer). How do you dig the files out?

First, the easy (and almost useless) way: View them on your camera. You can scroll thru the vids and tap on one to run it onscreen. But the screen is like a 2-inch diagonal TV set, which can’t show any level of detail. You need to export the file to your PC to view and zoom in on a big screen monitor.

When you bought the camera, you also bought a MicroSD card to hold your files. Remove that card from your camera and plug it into a MicroSD card reader. This is one of the ones I have, so I know it works.

Plug that card reader into your PC. It will come up as a USB drive. Like a thumb drive. You will find files in three types.

THM files

These are Thumbnail files. These are merely the thumbnail images you see when scrolling thru the video list on your camera.

LRV files

These are Low Resolution Video files. I mentioned earlier a recorded file in 4K30FPS is enormous. An LRV file is a playable low res version. If viewing a video on the tiny camera screen, this little file is used. Otherwise, these aren’t going to be of any use.

MP4 Files

This is your high resolution recording. That will be obvious when you see the enormous file size. MP4 is a format this is a bit nebulous in terms of its use of standards, but you should be able to load it into common video software/freeware.

Copy the files to review to your PC’s hard drive. Load them into your video software. My Windows 10 PC came with Microsoft Video Editor pre-loaded. I use that to expand the video to full screen and play it back. I can pause it and click thru frame by frame until I can read a license plate of a car going by. If I am viewing the upside-down rear camera view, a couple of mouse clicks rotates the view to right-side-up.

Finally, once I find a still image that displays what I need, I can store a screen shot to hand over to a lawfully interested party.

Wrapping It Up

With any luck, all you will do with these cameras is install them, turn them on at the beginning of every ride and off at the end.

But if you ever need a witness after an accident, a super high-resolution, 170-degree forward and rear-facing, image-stabilized record of the event is there for you – and if you ever need them, they will be more than worth the time and effort it took you to set them up.

DIY Bicycle Front (And Rear) Dash Cam, Part 2

This installment will focus on the installation and configuration of an ultra high resolution (4K and 30fps) DIY front and rear bicycle dash camera system.

This is a continuation of the topic introduced in Part 1, where we went over the rationale and parts list needed for a high-quality DIY front and rear dash camera solution.

Lets Get Started

We’ve purchased and received our parts. Lets install them and get everything set up. This article is going to be rather straightforward and by-the-numbers, as we already went over the reasons for rolling our own dash cam solution in Part 1.

Before we start bolting everything on, we will modify the scuba box.

The What?

Yes I said ‘scuba box’. Pretty much every budget action camera comes with a waterproof box as an included accessory. It lets you take the camera to the bottom of your swimming pool or lake or whatever. Putting the camera into the box makes it waterproof (and somewhat crashproof, too). Thats great, but what we really want is to make it easy to remove from the bike.

Most cameras have a threaded hole meant to interface with a standard 1/4″ camera tripod fitting. You can use that to screw the camera down onto a mount directly.

We don’t want to do this. When you are routinely using a camera on a daily driver bike, you need a quick and convenient way to take if off.

Why Take The Cameras Off?

It was literally just yesterday when, at my local Costco, I was beginning my process of locking the bike. A curious onlooker leaning against his parked car asked me “You aren’t going to leave those GoPro’s on there, are you?”

“Hell no” I Replied

“They go inside with me, and back on when I come back out.” I showed him how I just opened the scuba box door, disconnected the USB power cord and into a little go-bag they go (I re-use the bag that holds my bike lock), along with my removable taillights, tool bags and power banks. I also noted they are not expensive GoPro cameras. But still, two of them would be a pretty nice haul for sticky fingers.

And THAT is the real reason for the scuba box.

But its not quite ready yet. When I first started using cameras like this, I relied on their internal batteries for power. I quickly learned it was a pain to recharge the battery so frequently. Besides, battery life could be insufficient to get through a single ride.

The solution is to plug the camera into an outside power source. The camera still runs on its internal battery, but that battery is constantly topped up by the power source you connected. It (almost) never runs out and you can forget about it. More on this below.

So plugging the camera in is great, but we encased it in a watertight box, so you can’t plug anything in. Unless you…

Take A Drill To The Scuba box

The V50x camera – and every other action camera I have used – has a USB Micro-format combination data and charge plug. To get to that plug, we need to drill a slightly oblong hole in the box (speaking of which, when buying USB cords do not pick one with a big blocky plastic guard around it, or you’ll need to drill a huge hole).

In the left picture above, the hole is bigger than it needs to be. Oops my bad. But even so, an oversized hole like this should not cause a problem in even a heavy downpour. Still, you should be more careful than I was.

I said ‘oblong’ hole. To get that, I a) drill a round hole and then b) press against the side of the hole with the running drill. That grinds away just some of the top and bottom of my once-round hole. Then I incrementally test-fit and expand the hole some more until the cable fits snugly. There’s usually more hole than I need, but it never is so much it compromises the box’s structural integrity.

My Milwaukee step drill bits (I have this set) go thru the boxes cleanly in hot-knife-thru-butter fashion. So its easy to over do it. I have never ruined a box, but still be careful.

This set is part number 48-89-9222 and is the cheapest step drill set Milwaukee sells from what I see.

You can also use a simple old school drill bit and work it from side to side. Conventional bits are more difficult and leave more mess in terms of shavings. Once you get the hole drilled the rest is pretty simple.

Mount The Front Camera

First, this mount is more-complex than necessary. But it is what I consider to be a more ‘evolved’ method. I use a handlebar extension to raise the camera up high. This makes it more obvious to cars around me. I am using the following components, from the top down:

This thing is really up high but is not in my way

The Akaso V50x camera, inside of its scuba box. You can see the USB Micro wire coming out of the side connected to the USB port of the display, providing continuous power.
The adjustable forward camera mount. I added a red adjuster knob to it.
The camera mount is attached to a short handlebar extension, angled up to about a 2 o’clock angle. This helps because I need to mount a special light there, thanks to the particular setup of that bike. For your needs we only care about the extension because it raises up the camera. Zoom in. You can see it has two mounting arms (the product sells with just one). I had an extra. If you don’t, buy a second one and use the arm that comes with it. You could also buy a longer extension as those come with two arms, but I wanted to keep it small.

Step back from the bike a bit. That camera – raised up by the handlebar extension – *really* sticks out. Which is totally the idea here.

If you don’t have to mess with the added complications of a display and a light sharing real estate with the camera, you may still want to use that extension to raise the camera up. It is solid, doesn’t jiggle and helps make it obvious to others a dash camera is in use.

Keep It Simple, Stupid!

I have done a lot of these with a simpler mount – no extensions. The bottom-most picture below is an almost identical bike with the same displays and even the same funky light. That time I mounted the camera to the side.

For all of these bikes above, I just bolted the camera mount directly to the handlebars

If you are going this simpler route, it may be smart to put the camera on the left side as you face forward, where it will be more visible to neighboring vehicles. I hadn’t figured this out when I did these bikes.

Mount The Rear Camera

There is much less going on in back than on the front mount. I’ve only found one ‘best’ way to do this:

Attach the saddle rail camera mount.
Attach the scuba box to the mount, with the camera inside.
Attach the right-angle USB cable that feeds power to the camera.

Pretty easy. You will spend more time routing the USB cable to your power supply so it stays tidy.

Above: That short cable running thru the frame and seat rails is a seat leash, which, coupled to the dual-bolt seatpost clamp, makes it more time-consuming to steal the saddle and seatpost.

What Power Supply?

There are a few different ways you can go here.

Use the Internal Camera Battery

This is the way I did it for the first couple of years I used these cameras. At the end of a commute into my office, I pulled the camera from the scuba box and plugged it into a USB charger. At the end of my workday at home I did it again.

This was before I started drilling holes into the boxes, but we’ll get to that. When going this route, it is the least convenient because of the charging, but it is also the easiest to install with no extra effort.

Use An External Power Bank

Charging the camera twice a day was a pain on a daily driver bike. So I moved to an external power source. Since I still needed that scuba box for ease of removal, I drilled a hole in it so I could plug into the camera.

This is where my power banks go on both of my Bullitts

One power bank can easily power two cameras. A big power bank can do it for a long time. I like to recharge them once weekly, every Friday. I use a big power bank, but that big bank also powers other lights, so for just a camera you can use something smaller. Your mileage may vary.

My project parts list includes two options, both of which I use personally. One is a high-quality name brand. The other is a low-cost, no-name product with good reviews that is working just fine for me.

Use The USB Port On Your Display

This one is kind of a no-brainer. It makes for the cleanest setup. You can select options on the camera so when you turn the display on and off the camera goes on and off with it. Also you can skip the weekly power bank charges since you are using the main ebike battery.

However, not every display has a USB port. None of them have two ports to accommodate a front and rear camera. I have 2wd bikes with two displays so I can cheat, but thats true for almost nobody else.

You may want to just hook up one camera to your display and one to a small power bank. Or if you are handy with electronics, wire in a USB buck converter to your main battery for multiple USB ports.

Camera Settings For Dashcam Use

There are a variety of ways to fiddle with settings. In particular the power-on options to make the camera turn on and off automagically when you plug it in, power up your ebike display or turn on your power bank. I have found the most reliable method is where I manually start things up and shut them down. Letting the camera manage it, I’ve had one too many experiences where it has decided to take the afternoon off and shut down mid-ride for no apparent reason.

Driving Mode vs. Video Mode

Driving Mode is one of the 9 main modes that the V50x camera has for startup. Driving mode is a dedicated dashcam mode that – in theory at least – helps makes the camera completely automatic. When it senses power, it powers up the camera and immediately begins recording. When external power is no longer fed to it, it shuts down. That means if your ebike display comes on or shuts off, so does the camera.

That sounds great but in practice on these cameras, it literally does not work for some reason. What happens is the camera powers on exactly as expected, but then within seconds (before I have a chance to climb on the bicycle and start moving) it shuts off. Its not motion-activated because riding the bike does not trigger it to start back up again. If there is a way to make it work as advertised, the instruction manual is completely silent on it.

I prefer to use simple Video Mode, where I use the on/off and recording start/stop switches myself. Done that way it always works with no surprises.

For the settings below, if I do not list something that is on the menu, the setting is left in its factory default state.

Video Settings

Resolution	4k30fps This is the best setting for getting clear readings on a moving car’s license plate.
Image Stabilization	On You need this for jiggle-free video
Gyroscope	On According to the manual, this is the same thing as Image Stabilization. I turn them both on for the smoothest possible recording.
Loop Recording Time	3 minutes This sets how long each video snippet is. You want short loop recording time. A 3-minute video in 4k running at 30 fps will be well over 1 gigabyte in size. A longer loop sounds like a great idea until you try and work with a two gigabyte file in your video software.
Audio record	On It can’t hurt to have sound to go with your recording. Audio will be muffled thanks to the scuba box encasing the camera.

System Settings

Sounds	all enabled This just turns on all audio feedback to your touchscreen presses.
Distortion Calibration	On According to the manual, this is a helper for Image Stabilization. It narrows the field of view slightly.
Angle	170 degrees The widest angle possible. Since we’re trying to gather evidence in case of some sort of traffic accident, more is better.
Diving Mode	Off Do not mistake this for “driving mode”. It compensates for the lack of red light while diving under water.
WDR (Wide Dark Range)	On Allows greater detail in shadows when an image contains both bright and shadowed areas.
Auto Power Off	Off The camera can be set to power off during inactivity. Turning this off prevents the camera from deciding it needs a vacation.
Screen Saver	1 minute This just shuts the screen off to conserve the battery
Date Format	yyyy/mm/dd Personal preference. The format used for the onscreen date stamp
Date Stamp	Date and Time This sets the recorded onscreen stamp to show both date and time.

Wrapping It Up

With any luck, all you will do with these cameras is install them, turn them on at the beginning of every ride and off at the end.

But if you ever need a witness after an accident, a super high-resolution, 170-degree forward and rear-facing, image-stabilized record of the event is there for you – and it will be more than worth the time and effort it took you to set it up.

We’ll cover odds and ends, which includes video software to extract your little home movies, in Part 3.