How To Build An Ebike From Scratch

Introduction (you are here)
Step 1: Planning
Step 2: Hunting
Step 3: Tinkering
Step 4: Buying
Step 5: Assembling
Build Day 1
Build Day 2
Build Day 3
Step 6: Perfecting
Tools List

This is a Big One

This is an ambitious topic. There’s a LOT here. The entire series ended up being over 41,000 words, across 11 installments. Organization was a challenge, but I think it is laid it out in reasonably broad brush strokes that make sense. The Tools List at the end is organized in discrete sections for each Step.

What Does ‘From Scratch’ Mean?

I’m going to go through a complete project build that starts with a bare frame. I then add all the parts to that frame to make a fully functional electrically-assisted bicycle. We won’t be concentrating so much on electrical / motor specifications, as we will picking out every single part needed to build a bicycle. Right down to the shifter ferrules and cable crimps. Building a bike is a lot less intimidating when you have a complete list of everything needed, along with the tools required to install them.

This will be a ‘frame-up’ build: start with a bare frame and make it into an ebike.

I originally planned this article long ago. It was obvious to me there was a need for a sort of ground-up tutorial. I have participated in a lot of conversations with people who wanted a fun project, but realized quickly they were in over their heads.

Thats where I was myself the first time I did it – back before ebikes, in fact. I built my own analog bicycles back in the day. So when it came time to join the Dark Side and build electric bicycles, I leveraged what I already knew. I just had to add some bits to the parts list to account for the electrics.

Throughout this series, I will try to balance the value of taking a deep dive on a specific task, to just referencing that something needs doing, and perhaps linking you to an existing step-by-step tutorial. Some will be my own. I’ll reference many articles published on this site to cover a lot of that ground.

Where Am I Cheating?

I didn’t build the wheels. Really… wheelbuilding is a fairly advanced topic. For a person who needs help from a ‘how to build a bike’ article, that person should not also be taking on wheelbuilding lessons. Let a pro do it for you.

In my case, supply chain issues compounded by my regular wheelbuilder’s busy schedule meant I needed to find a way to get wheels professionally made for this bike… within a specific time frame, with specific parts. I’ll get into the wheel parts saga in detail in the assembly sections.

Anything Else?

Yes. We will be buying a battery. Not building one. If you need instruction on building a bike, learning how to also safely build a battery pack – something that can burn down your house and kill people if done wrong – is not something you should be taking on.

Also, I’m describing how to build THIS ebike from scratch: A full suspension, BBSHD-assisted, mid drive e-MTB. I chose this build because it is a pretty generic animal. Its not something weird like one of my gargantuan cargo bikes, or an all-wheel-drive beast. Those are great bikes, but not projects that appeal to the first time builder, nor are they of mainstream interest.

So… you aren’t going to see me discuss building a hub-assisted ebike. I’ve stated publicly in other fora I am done building hub bikes (with no plans to change this). However, I would like to, at some point, add a supplement to this build series to discuss what is done differently if building a hub-motor’d ebike from scratch.

Its not a major departure from this instruction set (its simpler) and only involves a few different specialty tools – chiefly a crank puller and a bottom bracket tool. And we’ll need to address torque arms. And…

… Never mind. Lets save that for another time.

Oh And There’s Also This

Lets call this a Mission Statement: DIY Does Not Have To Mean Half-Assed.

Look around on the internet for awhile. You will know exactly what I mean when you see all the projects where duct tape and zip ties are used as major components.

This project is intended to build a bike that is as close to factory-quality as possible. In fact, where it comes to the bicycle components themselves (brakes, headset, hubs, rims and so on) it will exceed them. We are not building a bike for profit here, but rather for excellence as a bicycle.

There will be things I deliberately do that spoil the polished look. But when the Perfecting stage is posted with the final production pics (not the bike shown on this page) you should be seeing a bike awfully close to that ideal.

Background on the Subject Bike

As mentioned above, I wanted to do this series some time ago. Unfortunately, after trying to get it off the ground, I realized I needed a fairly mainstream build to work with as it went along. It took awhile before that opportunity presented itself.

Recently I decided to build a small, self-contained, full suspension bike for use around town on short errands, and light trails. A bike I could easily toss into my car and haul back out again. Finally, this was the ‘normal’ bike for this writing project.

The Apostate is the result.

Quickee General Layout:

Lets take a brief look at how this is going to go down:

Step 1: Planning

Decide what kind of bike you want to build:

• Cargo? Full suspension mountain bike? Hardtail fatty?
• Put together a preliminary parts list to give yourself a ballpark idea of cost (don’t worry there’s a sample list ready for you to customize). Your parts list will be the backbone of your project management too.
• What kind of motor are you going to use? Hub (geared or direct drive)? Mid drive (from what manufacturer?).
• Where is the battery going?

Step 2: Hunting

Step 1 told you what kind of frame you want, in at least general terms. Now you get serious about buying one. Looking around the marketplace at real products will teach you new things you didn’t realize you needed to know. Read specs closely. Buy the frame that meets your needs.

Step 3: Tinkering

Now that your frame has been delivered, you can start confirming measurements so you know for-reals what the dropout widths are, seatpost diameter and so on. With the frame in your hands, you buy parts with confidence knowing they will fit (this includes your chosen motor, battery and controller). Having the frame in front of you rather just reading specs and seeing pictures is likely going to give you new – and perhaps unexpected – insight on the job ahead. You may change some of your parts decisions mid-stream.

Step 4: Buying

Now that you have looked long and hard at your frame, and made your final (?) parts decisions, its time to cast your net wide and start buying all the parts. The parts list you roughed out in Step 1 and finalized in Step 3 becomes crucial here. It will manage the entire process of buying and tracking parts shipped from myriad locations.

Step 5: Assembling

This is the big one. You’ve been receiving little boxes from parts shops for weeks. Now with everything in hand, the rubber meets the road: Put that parts pile together and make an electric bicycle. Since I did the actual build in about 3 days, I split up the assembly articles into three parts, each covering what was done on Days 1, 2 and 3.

Step 6: Perfecting

Once you finish assembly, the chances are near zero that you picked all the right parts the first time around. Expect to learn new things when you actually ride the bicycle. Maybe the handlebars would be more comfortable if they were a little wider, or the stem was a little shorter. Or longer. There’s almost always something that needs a tweak.

The Apostate was no exception. Right after the first test rides were complete I knew I wanted to make a couple of sizing changes. From there it went straight into the back of a car where it went riding daily for a week in The Grand Canyon. After that fairly extended initial period of use, I had a few additional things I wanted to change.

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Are we ready to get started? Lets go!

Step 1: Planning