Quick Release, Easy-Carry Ebike Battery Setup

Parking your ebike outdoors all alone? When shopping, my cargo bikes are locked but out on the street… but the battery goes in with me. Here’s how I do it without people thinking I am carrying a bomb.

Yes You Can Take ‘it’ With You

An ebike used for utility purposes is, by its nature, going to be left out a lot. You go to the store, load up a shopping cart, come back and fill up your saddlebags. You really want all the parts on the bike when you left to still be there. Especially after loading on 50 lbs of cat food, Oreos and diapers.

The most obvious way you keep the bike itself is to use a good locking strategy. I’ll save that for a different discussion. This time I will focus on how I protect the single most-expensive component on any ebike – the battery. Not by locking it up, but by making it so I can do a quick grab and carry it in with me.

By removing that battery, we are making that big heavy ebike into a boat anchor, which we can hope makes it at least a little less attractive to thieves.

Size (and Shape) Matters

What I am describing can be made to work with any shape battery, kept anywhere on your bike. What you see here works best with a squarish, oblong battery. In the pics below I am using a 17.5ah Luna Storm battery, which is pretty big and heavy (in part thanks to its powerful but not-so-energy-dense 25R cells). More likely, if you have a similar heat-shrink battery pack like this one, its quite a bit smaller and lighter.

I also keep a Luna Wolf Pack battery like this and do not use its magnetic mount. The battery is easy to quickly get off that mount, but leaving it inside of a bag like I describe here is, overall, easier than stuffing it in every time, taking it back out and so on. For packs like this (Wolf, Shark, Dolphin etc.) you could certainly bring a small pack and put it in/take it out as a part of your routine.

There’s more than one way to skin this cat, so what you see here is just a jumping off point.

Lets Get to It

This is the battery in its bag, just like it would be if I rolled up to the local Costco.

Ignore the charger cable in the front. I took this pic at work in my ebike garage.

If we zip open the bag, we don’t see a battery. We see an inner bag, along with that charger cable extending thru to the rear. The controller cable is in there too just out of sight (look closely and you can see it)

If we look inside the bag, we see the battery charge cable is in fact an extension running from the rear of the interior bag up and out the front. The motor cable – an XT90S connector – also has a short extension between the battery cable and the motor cable. The idea is this: when routinely, frequently detaching and reattaching the cable, if there is any wear its on a cheap, replaceable extension and not a critical, live/hot cable coming directly off the battery.

Disconnect the cables and give a tug to the inner bag. Here its shown halfway out but you will just pull the thing out in one motion.

When I leave, I generally put the cables back inside and zip it only halfway-ish, so its obvious there’s nothing worthwhile to steal inside. Move along.

Annnd here we are. the cables are shown sticking out of the inner bag. You will want to cap those for safety’s sake. I use cheap plugs I got a bagful of on Fleabay for a couple bucks.

And yes… as-is I have had someone ask me “what is that a bomb?” … only half joking and ready to clock me if I make a sudden move. So stuff the wires in the bag so they don’t stick out.

Tell the Bomb Squad to cut the red wire

Done! Wires are capped and stuffed into the bag in 5 seconds. The sling strap goes over your shoulder for easy carry. I just lug it to the nearest shopping cart and put it in the bottom rack with my helmet and off I go.

This is just a 3L hydration bladder pouch, the sling strap that comes with it and a shoulder pad I swiped off another strap I wasn’t using.

Parts

Its a really short list with one item on it.

Hydration Carrier

You see above the Blackhawk S.T.R.I.K.E. carrier in use. Purchase link is here. Yes, the name is a tad ridiculous. But this pack is minimalist and is just durable cloth with no insulation or padding. Its easier to stuff into a confined space. Mine came with a super sturdy velcro sling strap.

Another that is well made (and a tad smaller for a tighter fit is sold by Voodoo Tactical. It comes with thin backpack-style shoulder straps that don’t take up *too* much space in your triangle bag and are not enormously fiddly when stuffing back in there.

Another one I use (with my Luna Wolf pack) is this government-issue USMC carrier. The link is to a brand new unit. I got mine surplus and cheaper on Fleabay. This pouch has no straps (you can clip on your own from a duffel bag if you like) and it is the opposite of the Blackhawk carrier: Its thick and padded. I can still stuff it into any triangle bag I have despite this. Its great as a protective layer over a battery.

Wrapping It Up

There are lots of ways to do this. How I do it is no big deal. Key takeaway here is to find a method that works for you so you can swiftly grab the battery, go off to your next adventure and then come back and plug right back in again.

Frankenstein Boots For The Ursus Jumbo

I had an aftermarket kickstand that was too short. Here’s a way to add a tough-as-shoe-leather extension that should last forever.

My Mongoose Envoy received a much-needed upgrade to its kickstand when I upgraded to an Ursus Jumbo, whose much-wider (18″) leg platform keeps the bike stable on uneven pavement or when it was heavily loaded.

The stock Envoy stand works well unless you have 100 lbs of groceries loaded up. Do that and .. oops you gently bumped the bike! Over it goes and boy does your life suck. You’ll have to unload the bags, stand the bike back up, uncrack the eggs and load back up again. Same deal happens when parked on an incline.

The Jumbo solved this problem given its obvious mechanical advantage.

Jumbo on… Skinny tires. Problem solved.

… until I put some big poofy 26×2.8 Vee Speedster tires on the bike, which raised the frame up probably a full inch; maybe more. That meant of the two legs that Ursus kickstand has, only one of them was on the ground at any one time. At first it was kind of fun to be able to lower the stand and roll the bike around, or out of my way with ease. Then I saw what a bad idea it was on a sloping driveway. The bike was happy to tip over. For a cargo bike that will be loaded, that has to change.

Fat tires tall. Fat tires good. Kickstand barely touching ground bad.

A couple of methods presented themselves. The first was to lower the stand by shimming the base. While I would have been able to find a longer M10 bolt to do the job, making a shim that will actually work is a lot more complex than just throwing in some washers and calling it good. Absent a mill and some billet to do some custom fabrication, shimming was a no-go. So, since I can’t make the base longer, that leaves only the legs. I had to make them longer.

Shoe Goo… To The Rescue!

I should be brought up on charges for that header. Couldn’t help myself, and besides its true. Shoe Goo is a shoe repair tool that is essentially replacement shoe leather. Or shoe adhesive to hold your precious Converse All Stars together after they came apart. Or both. For you shade tree mechanics, if you think of it as a hard rubber equivalent of JB Weld … you have it down.

I suggest buying the big tube. I used about one full tube per side.

So what I decided to do is to stick my kickstand upside down in a vise, block off the bottom of each leg with some painter’s tape, fill the resulting cup with goo and let it dry. Peel off the tape and I’ll have a longer kickstand with a new, tough-as-nails rubber foot.

It turned out to be a bit longer than that, and took quite a bit more time to cure. But layering on a bunch of goop to the bottom of the kickstand is the short version of what I did here. And best of all, it actually worked.

Time For Plan B

What you see above is only the first attempt, using green painter’s tape. And while it worked (see photos sans tape) it became clear just by looking at it I could expand the ‘foot’ to a much greater size if I taped off the base and poured in more goo. You can see this in the last two photos where the tape has been removed. the foot of the Jumbo has essentially a large hole in it that you can further tape off, then fill in. this time you need to tape halfway up the leg as that hole runs thru to the front of the stand, and your tape will provide a deep chamber for the goo to fill and harden into.

This time I used silicone tape, which I discovered by accident does not stick to Shoe Goo! Knowing that, I was able to use a scrap of tape to help sculpt the slowly hardening-but-still-pliable glob of goo. That matters because as this stuff dries – and then cures – it shrinks into itself. You will need to come back every couple of days to apply another layer. And when at some point you call the job done, you will want to let this material sit for at least another five days.

So if you are doing the math here, that means this is going to take time. I spent a total of about two weeks applying, filling again after it shrinks down and then letting it cure so its stable with a bike standing on it.

Is it worth the trouble? Well, I spent about $8 on two of the big tubes of goo and another nickel or so on a length of black rubber mastik tape around each foot to pretty them up. When I was done, I had a kickstand that completely solved my problem, and I can expect to be able to use for the life of the bike. If you want, Shoe Goo comes in a black formula that will have a matching look… but it costs more than double what the clear stuff does.

If You Do This…

I felt my way thru this project and learned as I went. The way YOU want to do it is skip the first stage with the green tape entirely. Use the silicone tape to wrap the entire foot. Wrap snugly at the bottom of the channel you want to fill, and as you get to the top – the actual extension to the base – do not wrap that tight, just do it loosely and make sure the tape wrap adheres to itself. Then inject the goo with a narrow nozzle (there are kits out there that have them) deep into the channel you just created, filling it from bottom to top until you have a single large ‘sole’ wrapped in the silicone tape.

Then, walk away from it for 24 hours. Add more goo as it cures and shrinks down. Use a scrap of silicone to pat down the added goo so it forms a nice smooth surface. If it seems solid, remember thats just the outer layer and inside its still like jelly. I went on a week’s vacation after I thought I had it done and it was pretty solid.

So… Wait it out. the results are worth it.

Mongoose Envoy Update – Cargo Deck 3.0

When I originally used a double-kick longboard deck to make an XL cargo carrying top for my Mongoose Envoy project, its 33″ (84cm) length and 10″ (25cm) width seemed really big.  Considering I was coming from a world of ordinary bike racks on normal-wheelbase bikes, it was quite large.

img_20190929_170059
Deck 1.0, shortly after installation. I try to avoid the word “festoon” to describe a bike build so those two little bags in back went away soon afterwards.

The XL deck worked *splendidly*.  I had no complaints whatsoever, and I could have left it like that forever.  However…

The board, by virtue of its 33″ length, only used 4 of the 5 available rows of M5 mounting bosses.  So I had definitely left some available space on the table.   In a perfect world, I would have found a longer version of the same board:  Say a 40″ double-kick.  But alas, at the time, I couldn’t find one.  I also could not find another board that had this same 10″ width.  Everything else was more narrow.  But I could get close with what became Deck 2.0: a 40″ x 9.75″ kicktail longboard.

It installed easy enough.  I painted it with Rustoleum truck bedliner to pebble the surface just right so it held onto gear a bit.  I used the same inverted grub-screws for drill guides like I describe in the Deck 1.0 post.   And the rack was now long enough so it used all 10 mounting points on the frame.  It couldn’t be more solid – the board is 8 layers of Canadian maple – and makes a sturdy handle I can use to pick the bike up and move it around from the rear.

And… its 40″ long.  With that solid center mount kickstand, its handy to have a coffee table with you wherever you go.  From a cargo standpoint I could easily net down a 3-foot duffel bag on top and still have room to spare.

Still, It didn’t work out quite the way I planned.  I thought I wanted to move the rack further forward so I could mount gear under the seat.  So I did that and the idea was to take up the otherwise wasted space just behind the seat.  But once I had it set up, I found the space effectively unusable.  I needed to keep some room back there for the Thudbuster to flex as part of its normal duty cycle, and my legs hit whatever was jacked up all the way to the front.

I also missed the front kick on Deck 1.0, which provided a natural slope to keep gear from sliding forward under hard braking.  As a substitute threaded a couple of M6 bolts directly into the M5 holes (no fixing nuts needed) that existed for the nonexistent trucks. These held down a simple 50-cent L bracket wrapped in my favorite padded rubber mastik tape.  It worked but in the end I removed it for aesthetic reasons. 

Lastly, I mounted the board just a hair too far forward, and occasionally I brushed it with my legs during the pedal stroke.  Not a big deal unless you are a perfectionist. I didn’t want to redrill the holes so I could move it back. It was a minor imperfection. So I left the board on for several months and it worked great.

But I did acquire a 44″x9″ kicktail longboard from Magneto, with the intention of using it on the back of a planned Surly Big Fat Dummy build.  That plan went away, and the 44″ board had no home… so what the hell lets put it on the Envoy.

While I was at it, I decided to make a couple of changes.  First of all, the Magneto board comes with an aggressive, highly abrasive grip coating on it.  I took an orbital sander and smoothed it down some so it would not potentially wear thru duffel bags and bits I’ll have netted down on top of it.

Next, I painted it with the same Rustoleum truck bed coating spray.  This took a little more of the harshness off the grip coating and gave the deck a tough finish.  I also decided to two-tone it with some medium gray paint on the underside.  It turns out this is totally invisible unless you are laying on the ground looking up at it.

Also, instead of re-using the 25mm post spacers, I bought new ones 40mm tall. These required longer 75mm bolts.  Having used the rack already for several months with 25mm between deck and frame, I wanted more room to move my hands in and out attaching/detaching net hooks, passing cinch straps thru etc.

It came out great.  This Magneto board is a sandwich of bamboo and maple so it has a touch of flex to it. This made  bolting to the somewhat uneven frame easier.  Its still rock solid despite the now 4″ longer tail out the back, which I do not notice from a convenience standpoint (its not too long, which I worried about).  The 40mm spacers are an absolutely perfect height to let me get my hands in there without being so long they compromise the solidity of the mount.

The board has a front kick, but it turns out it can’t easily be used, for the same reason I couldn’t use the front few inches on the 40″ deck. However it is slightly narrower than the shorter board so even though it is just as far forward, I no longer hit it with my legs.

As a gear-stop/bumper, I wanted something a bit more substantial than the half-assed L bracket I used on the shorter board, so I used a couple of the leftover 25x13mm M5 spacers, plus some 10x10mm spacers I had in my parts bin, to create some ‘electrode’ stanchions fore and aft.  With the large area washers at top, they either provide a bumper for gear stowed on the deck, solid purchase for a hook, or a place for my net to grab onto in the very back. Silicone grip scraps fit right over them to ensure the edges of the top washer don’t bite into my gear.

The two forward stanchions are extended from the deck mounting holes and go all the way thru to the frame.  They use 110mm M5 bolts.  The two in the rear use the rearmost holes drilled for the trucks. These use matching countersunk bolts and finishing washers like those used with all the other mounting hardware.

img_20200514_163026
A bit of scrap silicone handlebar grip tucks under the rear stanchions to provide a smooth, grippy place for my net to glom onto. You can stretch the net all the way back and over the kicktail, too.

Compare this pic above to the 40″ board and its clearly longer, but functionally, the increased length is no bother.  If I had to fit the bike on a train or bus then this is not the best solution.  At some point, if I need some extra carrying space out back, its available.  At present, I have an extended amount of space for my round 40″ duffel.

… and a bigger coffee table.

The BBSHD: Musical Chainrings

It seems inevitable.  When I build a bike, I go through front chainrings trying to get the gearing just to my liking.  My Mongoose Envoy build has pretty much set the world record for tweaks in this regard.  But gearing wasn’t the problem so much as chain alignment.  Alignment is one of the most talked about issues with mid drives and up to this point I have not had to work too hard to get it right.  This build, not so much but I think I finally got it (like $350 later).

While dealing with this I have fooled around with three different sets of crankarms (160’s, 170’s and 175’s).  Not the subject here so if you notice the different crankarms in the pics, I am ignoring them on purpose.

Sidebar:  When building the Surly Big Fat Dummy, I found exactly the same thing as I did here insofar as chain alignment is concerned.  And used the same solution – the USAMade adapter listed as an Honorable Mention below got pulled out of the parts pile and put to use.

The Right Tool For The Job

The Mongoose build is a first for me in many ways.  One thing in particular:  the BBSHD fits the frame really well.  Its a 68mm bottom bracket with absolutely zero chainstay obstruction for the secondary housing.  So I can butt the motor right up against the bottom bracket.  Further, its a lonnnng way back there so chain alignment and misalignment – an inevitable concern with an HD build – is a lot more forgiving since the angles are gentler thanks to the longer reach.  On this bike, if I want I can even forego the offset non-drive side crankarm and the pedals are still easily centered under me.  So the HD is a great fit here.

About That Job…

The Mongoose is a cargo bike.  So it hauls heavy stuff (usually groceries).  It has a secondary job as an unladen backup commuter, but primarily it needs to be optimized to start from a stop while the entire system – with me – weighs 400-450 lbs (180-204kg).  I have really loaded it that heavily so this is not a theoretical exercise.  So I want a big-ish chainring for when I am pedaling fast and light, and still need to be able to get to the big cogs in the back for when I am loaded up and chugging along like a two-wheeled freight train.

Plan A:  Luna Eclipse (42T)

The Luna Eclipse is one of the best BBSHD chainring setups on the market, with a unique ‘wicked’ tooth profile meant to eliminate the possibility of a chain drop under extreme use.  It also has the most extreme internal offset of any chainring option.  This will do the most to overcome the grief visited upon the BBSHD builder by that drive’s secondary housing sending the chainring way out to right field.

Its also gorgeous.  The gunmetal finish I chose matched beautifully with the dark grey frame.  Unfortunately 42T (which is the standard for full-offset chainrings as any smaller and you can’t clear the secondary housing) was not large enough to keep me from clown-pedaling when riding the bike as a commuter.  There was another problem:  Chain alignment.  Running that smaller 42T ring with the smallest rear cog resulted in, after only a few weeks, a whole lot of wear on the inside.  This is why mid drive builds demand the most out of the builder in terms of thinking things thru.  Time for Plan B.

IMG_20200503_123800
Its not ruined yet, but its lifespan sure has been shortened.  this was only a couple hundred miles of wear.

The Eclipse is a proprietary chainring platform, but fortunately other sizes are available.  the largest of which is what I tried next.

Plan B:  Luna Eclipse (48T)

So Plan B was to swap in a Luna 48T ring onto the Eclipse center section to fix the clown pedaling, and to stay the hell off the 12T small rear cog to deal with the alignment issue (I am using a welded together steel cluster for durability and the 12T is alloy and not a part of the welded cluster, so its better to stay off it for the sake of longevity anyway).  I thought that 48T/14T on this bike was the perfect sweet spot.  A small front ring is best when its on cargo duty, and a large one is best when its a commuter.  48T, when used in conjunction with upshifts, gave me pretty much everything I needed.

Pretty much but not everything.  First of all, remember the deep offset of the Luna ring?  It moves the chain inboard 24.8mm which *usually* eliminates the damage the BBSHD does to chain alignment.  Not on the Mongoose, whose narrow bottom bracket effectively papers over all of the sins committed by the motor (at this time I had not yet fully figured this out).  So, as I found with the 42T ring, it was inset too far, even when I stayed off the smallest cog.

So Plan B helped, but it didn’t solve the problem.  After only a couple weeks (I am now checking carefully and frequently) I saw the beginnings of the same wear on the inside of the chainring.  Like the 42T, I had to retire this thing fast so I could use it on some future project.

IMG_20200503_123820
Not as bad as the 42T, but still bad.  Both this one and the 42T looked perfect on the other side.

Sidebar: A mid drive chain powered by a 1500w motor is a chain saw when it comes to components rubbing against it.  That is just a reality of a mid drive and you have to deal with it as part of your design/build process.  When you get it right, you are golden for thousands of happy miles.  Get it wrong and you are sawing thru chainrings and cogs like nobody’s business.

Plan C: Lekkie Bling Ring (46T)

So now what?  42T was too small.  48T was more or less just right.  And the chainring offset that lets me use the inner cogs at great alignment still needs to be reduced or I can’t use anything but the lower gears.  Lekkie has a Bling Ring available in 46T.  It has the same internal offset their 42T ring has and, since I use them on two other bikes I know they are top quality.  At 18.3 mm its offset is quite a bit less than the Luna.  So I got a 46T.  I also added a 2mm spacer underneath it, further reducing the chainring offset to 16.3mm.  That is a whopping 8.5mm less than before so I hoped I would be good on the smaller outer cogs and still let me use the big inners.

And, pretty much, it was.  Chain alignment didn’t seem to be much of an issue, although it still wore down a bit more on the inside.   I was also able to shift up to the biggest cogs in the rear for very low gearing options.  Those are important on a full cargo load and if I am dealing with hills.

But… I flat out missed that 48T high gear for commuting.  And I was still seeing – very slight but noticeable – wear on  the inside of the chainring teeth from the chain, which was still visibly angling outboard a fair distance.

IMG_20200503_123847
This one was on for a few months and had 8.5mm less offset.  But it still shows signs of premature aging.  This was undesirable but livable.

I decided to try an extreme option I had not previously considered.  But on this bike, where all of the normal chainring offset stuff doesn’t seem necessary, it might actually work.

Plan D: Luna 130 BCD Adapter and Wolf Tooth 48T Ring

BBSHD chainrings are generally all proprietary to the platform.  Not so in the cycling world, where chainrings are universal, needing only to match the proper Bolt Circle Diameter for the chainring bolts.  Match the BCD between crankset and chainring and you are good to go.  There are adapters out there in the world that allow a Bafang motor to use standard 104mm and 130mm BCD chainrings.  The problem is they don’t give you anywhere near as much inward offset.  But given my experience so far, maybe I can live with that.  They should fix my alignment on my ‘commuter’ cogs, but will I still be able to use my ‘cargo’ cogs?

In addition to the LunaCycle 130 BCD adapter, I also chose the Wolf Tooth Drop Stop chainring as those rings are best-in-show for this sort of thing on a mid drive.  Attachment to the adapter was a little different than the usual chainring-to-crank operation in that its backwards.  The chainring bolts onto the inside.  I was able to play some games to good effect:  I reversed the chainring so it is logo-side-inward.  Not as pretty, but doing that lets me take advantage of the countersunk bolt holes on what is normally the outboard side.  The countersinking let me mount a bolt so it is almost flush with the ring, which in turn is butted up almost on top of the secondary motor housing.  With the countersinking it now has plenty of clearance.

Plan D Results

FINALLY.  Everything is working right.  The reduced chainring offset means my 14T cog (still not using the 12T for the reliability issues mentioned above) lines up straight back.  This outboard shift did affect my inner cog alignments but I can still get to all of them but the biggest 32T.  I’m comfortable with the angles on all but the second-largest 30T for long term use, and in a pinch, that 30T will work fine.  I just don’t want to stay on it for a week.  So this 9-speed is now a 7-speed and as DIY mid drives go thats still better than a lot of builds can manage.

And worth mentioning, like a lot of what they do, the CNC-machined Luna adapter is freaking gorgeous, and very precisely manufactured.  So much so it really stands head and shoulders above another adapter I got my hands on and was able to compare it directly to.

Honorable Mention: USAMade 130 BCD Adapter

I was surprised at how well this worked and how nicely it was made.  The part only cost me $29.99 on Amazon.  Still, it was Made in USA, well machined and rock solid.  The only things I didn’t like about it was the fact it was machined a bit too heavily, which meant it placed the chainring a millimeter or two further outboard than was necessary, and in this game millimeters count.  Further, as you can see above I was able to reverse the WolfTooth ring and take advantage of the bolt head countersinks.  That didn’t work with this part as USAMade countersunk the outside edge of their part, which made the bolts too long to allow my trying the same trick on the inside, where I needed it.  For a different build it might work fine so I am keeping it for my parts pile.

As for the Stone chainring seen on the USAMade adapter (scroll up to the title image at the top of the page), thats a Chinese Special that ran less than the godawfully expensive Wolf Tooth.  Its noticeably lighter in construction than the WT and I’m not sure I am sold on the tooth profile.  This ring will sit in my parts pile waiting in the wings as an emergency replacement.

Mongoose – Chapter 8 (Low Cost Builds)

So in Chapter 8, I put up a Build Sheet.  If you do all the math, you will find my $750 bike turned into a $3600 bike (some bits, like the battery, I already owned and just plugged in so cashwise I am not out the full parts total).  Given how expensive quality cargo bikes are, and the level of quality I have now, I am very happy with that cost vs. benefit.  I have a really solid frame and top quality components, and a bike that is probably the best all-around transportation/auto replacement bike I have ever owned.

But what of all of this was actually necessary?  I build bikes as projects.  Generally, I am more concerned with making the bike the best it can be.  I don’t pay as much attention to final cost as most people would.  Especially since I oftentimes upgrade in bits and pieces, which is less of a shock to the budget.

Based on my experience with the stock Mongoose bike – seeing first hand what worked, what didn’t and what I changed because I had more money than brains – I can see a different way to go that might be of a lot more interest to people who just want a good bike that doesn’t break the bank.  For the record, I’m of the opinion that the Mongoose Envoy represents a significant break from current cargo bike offerings in that it can be built into a first class solution for a lot less, thanks to its bargain basement starting price.

So… lets build a few different configurations using my kitchen-sink, spaghetti-against-the-wall build.  In the end, I replaced everything but the frame, headset and fork.

All prices are in US Dollars.  The last two builds are non-electrified.

Build #1:  Just The Very Basics+Assist ($1,807.48)

This is a low-cost build that changes only the things that I think must be replaced.

Right off the bat, you can see I left on the Magura 4-piston MT5 brakes, and the great big (but relatively inexpensive) thick rotors.  These brakes work so smoothly and so well when I have had this bike fully loaded.  I think you’d be insane not to take any and all uncertainty completely out of your braking equation.  These brakes are not overly powerful when you consider the duty cycle they will have to put up with.  Safety first, but this choice also guarantees trouble-free ease of use.

This build uses the BBS02 because it is lower-cost and still does a spot-on job.  You can see from my motor choice post that if I did not already have other BBSHD bikes in my stable, I would have chosen the ’02 for this build as it is ideally suited for the cargo bike job.  The cost below does upgrade to the mini color display; adding $40.  Knowing the different displays as I do, this is well worth that minor upcharge.

Note I changed the shifter… that has to happen thanks to the change in brakes.  The stock brake levers are combined with shifters (cheaper that way, I bet) and if one goes, so must the other.

Mongoose Envoy Bike               Amazon               731.49
Magura MT5 disk brake set         bike-discount.de     137.00
ISH-203 203mm rear disk adapter   bike-discount.de       6.86
QM5 203mm front disk adapter      bike-discount.de       6.86
Tektro 203-17 downhill rotors (2) ebay (hi-powercyles)  42.40
MicroSHIFT TS70-9 shifter         Amazon                22.88
BBSO2 motor kit                   Luna Cycle           490.00
   68-73mm standard motor
   mounting hardware
   wiring harness
   speed sensor
   basic crankarms
   Luna 500C mini color display
   Universal thumb throttle
Battery Solution
   52v 12.5ah battery pack, basic Bicycle Motorworks   369.99
   pack construction, 50a BMS and
   Samsung 25R cells

Build #2: Change Out The Drivetrain ($1,933.00)

Includes everything above, plus the following, which adds $144.61 to the build price.

Everything From Build #1 plus...
KMC X9.93 chain (7 feet/more links)  Luna Cycle   57.75
Shimano HG400-9 12-36T cluster       Amazon       25.99
Shimano RD-M591 9spd derailleur      Amazon       41.78

This takes out the frankly bottom-end Shimano drivetrain and in its place substitutes a smooth-as-glass 9-speed click-shift setup.  Yes the chain is expensive but if you want to do a mid drive right, you have to pay attention to the chain and the rear cluster, which in this case is a durable, steel, welded-together unit that will give longevity and will not tear into your cassette body.

You can get a strong steel cluster with an 11T small rear cog, and I suggest you resist the temptation.  11T cogs are always problematic on mid drives in the first place.  On a cargo bike the problem is worse.  The speed you can achieve dropping that one tooth is likely unattainable anyway.  Especially when you factor in the weight and the motor-bogging that will occur under load.  Don’t do it.  Get the 12T.

Worth noting:  The stock Mongoose 8-speed cluster is also a welded steel unit so its just as survivable.  Also the Mongoose chain is an 8-speed KMC, so its likely just as durable.  The weak links – no pun intended – are the rear derailleur and shifters.  Mine worked poorly although I intended to replace it with a 9-speed from the get-go, so I didn’t try to adjust it into compliance.

At this point, we have a really first class electrified cargo bike that stops easily, shifts smoothly, will survive over the long term thanks to the components we plugged into the drivetrain… and we’re still under 2 grand.

Build #3: Add a Front Rack ($1,988.48)

Yikes we’re still under 2 grand here!

Everything From Build #2 plus...
Front Rack 
   Axiom Streamliner Front Rack  Amazon       46.99 
   Delta AxelRodz skewers        Amazon        8.49

Adding the front rack greatly increases your versatility.  For mine, I use waterproof RockBros 27L panniers similar to Ortlieb rolltops: They are big, carry a lot and mount about 2″ low on the rack.

Note my discussion of the installation of this rack in the Odds and Ends post.  You’ll need to spring for about 20 stainless 5/32″ fender washers to fit the rear AxelRodz skewer onto your front axle.  This sounds crazy but really, it works very well.

Build #4: Beef Up The Drivetrain ($2,187.43)

We’re adding almost $200 with just these next two parts.

At this point, since we are building with a BBS02, we’ll want to address its weak links a little differently than I did with my BBSHD.

The Lekkie chainring gives you some offset to bring your chain line back into alignment, provides a tooth profile that eliminates any chain drops and lasts, essentially, forever provided you do your part as described in the mid-drive section of the motor musings chapter.

Everything From Build #3 plus...
   Lekkie Buzz Bars (crankarms)  California-ebike    99.00
   Lekkie BBS02 46T chainring    California-ebike    99.95

As for the crankarms, those are self-extracting, quality bits of forged alloy, versus the low-end Chinesium alloy used on the stock arms.  Those square-taper arms are often replaced, and the fact they only cost about $15 each makes said replacement relatively painless… but never having to replace them in the first place is an idea that has some merit.

You can consider the crankarms an optional option and see if you pedal hard eough to make them fail, which you might not, in which case you’ll save yourself a hundred bucks.

Build #5: No E-Assist, Proper Parts ($1,081.69)

What about just treating the Envoy as a ‘donor’ to make an analog bike?  Take advantage of the great frame and replace the iffy components to make yourself something really good for really cheap?

I did not throw on the hand built uber-wheels, or change the tires.  Both of those components work well on the stock bike.  Sure I think custom wheels and upgraded tires are a good idea, but they are icing on a cake and, particularly with the wheels, spike the build price up considerably.

I focused on turning the bike into a silky-smooth-running, safely-stopping hauler.

  • The drivetrain – excepting the front crankset – was replaced with a great Shimano 9-speed long cage derailleur
  • The chain may seem expensive, but you’ll have to buy two 9-speed chains to make one long enough to fit this bike, or just buy the super-strong one I did that is in one piece already with no potential mid-chain weak spots where the two chains would otherwise be attached together.
Mongoose Envoy Bike                Amazon            731.49
Magura MT5 disk brake set          bike-discount.de  137.00
ISH-203 203mm rear disk adapter    bike-discount.de    6.86
QM5 203mm front disk adapter       bike-discount.de    6.86
Tektro 203-17 downhill rotors (2)  ebay               42.40
MicroSHIFT TS70-9 shifter          Amazon             22.88
Shimano HG400-9 12-36T cluster     Amazon             25.99 
Shimano RD-M591 9spd derailleur    Amazon             41.78
Shimano FD-M591 derailleur (front) Amazon             29.95
KMC X9.93 (two of them)            Amazon             36.48

Build #6: No Electrics, Fully Loaded ($1,566.41)

This one has almost everything but the kitchen sink thrown in for max comfort and quality.  Here again though, I left off the hand built wheels.

  • The Thudbuster LT is pricey but its such a big change to the comfort of the bike, a top build has to have it.
  • $90 for a kickstand is hard to choke down, but if the bike falls over once at the store with 100 lbs of groceries in the bags… it doesn’t seem quite so expensive.
  • Those Jones bars are just too comfortable.  Nothing wrong with the stock bars… but if we are throwing on stuff to feel good, these have to be on the list.
  • I use the RockBros panniers with my own front Axiom rack and decided to include them here.  They are big, waterproof and inexpensive.  While you do not want to overload your front rack, these can carry jumbo bags o’ tortilla chips without squishing any.  So as usual, size does matter.
Everything from Build #5 plus...
Thudbuster LT 27.2 XL            Amazon      119.99
Ursus Jumbo Superduty kickstand  Amazon       79.99 
Jones H-Bar SG Loop Handlebars   Jones Bikes  79.00 
Jones 205mm Kraton Soft Grips    Jones Bikes  20.00
Front Rack 
   Axiom Streamliner Front Rack  Amazon       46.99   
   Delta AxelRodz skewers        Amazon        8.49
   RockBros 27L Panniers         Amazon      108.99

Wrapping it all up…

The first four builds above address all of the functional weaknesses of the $730 Mongoose Envoy.  Do these things and you have

  • upgraded an analog bike into a solid electric performer
  • addressed every functional weakness in the original bike

The last two builds take a look at the same thing, but go in the direction of making the bike the best it can be without a motor.

One functional item I am leaving off here is a heavy duty wheel build.  While I have one in progress, and its on the build sheet, the fact is I have not yet killed the stock wheels.  Nor have I ding’d them.  They are still nicely true, and my desire for a 30mm internal, survive-the-apocalypse set of wheels can be argued as me overdoing it… again.

There are a lot of other line items on my personal build sheet that are not discussed on the electric builds.  Stuff like the Thudbuster seatpost, or the Jones bars.  These address personal comfort issues that don’t need to be there.  Those are items you can spring for individually over time… or not.  You know how the bike upgrade thing goes…

So have at it!