New to E-Bike Building – Need Advice from the Pros!

[Rhapsody]

Hey guys!
I’m building my own DIY e-bike from scratch — frame, battery, everything — and I’m learning as I go. If you’ve built one before, I’d love to hear your tips or connect for occasional guidance. Just trying to avoid rookie mistakes and build something solid.

Thanks in advance! The bike I want to build is going to be a surron clone. Aesthetically pleasing but not as efficient... I would love to learn under whoever as far as they can help me complete this project.

 

[amberwolf]

We'd need to know complete details about the project, how it's going to be used, and under what riding conditions, in order to provide useful feedback.

Otherwise I could only recommend reading other build threads, troubleshooting threads, etc., that cover whatever it is you're going to do.

 

[E-HP]

Do you weld aluminum?

 

[bananu7]

The general tip would be to fit the project to your fabrication capabilities. Nothing is truly "from scratch" and you will need to rely on the supply chain sooner or later. I suspect you won't be making your own suspension, tyres or battery cells. So it's pretty important to decide what parts you want to make (e.g. frame, seat, battery enclosure) and what you want to buy (literally everything else).

Even when assembling existing components, there's a lot of moving parts (literally!) and getting fitment right is always a challenge. Basically there are two ends of the spectrum here: design everything in CAD and rigorously maintain everything up to spec, replacing and modifying until it all fits, or not design anything and just rig everything in situ. You'll see in the existing builds that something in the middle generally yields acceptable results for one-off builds.

Then there's the decision order. You need to lock into certain choices because they will impact everything else. The thing I personally would recommend would be to start with the exact tyres you want, in the sizes you want, and build everything in sequence from there - rims, spokes, hubs, swingarm and front suspension, and finally the frame itself, with the caveat that you should know at least more or less what the battery will be like. This should minimize backtracking and will ensure that the project has parts that are optimally strong/lightweight.

 

[Rhapsody]

We'd need to know complete details about the project, how it's going to be used, and under what riding conditions, in order to provide useful feedback.

Otherwise I could only recommend reading other build threads, troubleshooting threads, etc., that cover whatever it is you're going to do.

The document attached has a summary of everything I plan to do, problem is I need someone with substantial knowledge in e-motorcycle building and its intricacies to guide me. Where I stay e-motorcycles are quite rare so there are no laws or limits to my creativity. I just need people to mentor and guide me on this project. Thanks in advance!

 

[Rhapsody]

The general tip would be to fit the project to your fabrication capabilities. Nothing is truly "from scratch" and you will need to rely on the supply chain sooner or later. I suspect you won't be making your own suspension, tyres or battery cells. So it's pretty important to decide what parts you want to make (e.g. frame, seat, battery enclosure) and what you want to buy (literally everything else).

Even when assembling existing components, there's a lot of moving parts (literally!) and getting fitment right is always a challenge. Basically there are two ends of the spectrum here: design everything in CAD and rigorously maintain everything up to spec, replacing and modifying until it all fits, or not design anything and just rig everything in situ. You'll see in the existing builds that something in the middle generally yields acceptable results for one-off builds.

Then there's the decision order. You need to lock into certain choices because they will impact everything else. The thing I personally would recommend would be to start with the exact tyres you want, in the sizes you want, and build everything in sequence from there - rims, spokes, hubs, swingarm and front suspension, and finally the frame itself, with the caveat that you should know at least more or less what the battery will be like. This should minimize backtracking and will ensure that the project has parts that are optimally strong/lightweight.

The document attached has a summary of everything I plan to do, problem is I need someone with substantial knowledge in e-motorcycle building and its intricacies to guide me. Where I stay e-motorcycles are quite rare so there are no laws or limits to my creativity. I just need people to mentor and guide me on this project. Thanks in advance!

 

[chuyskywalker]

problem is I need someone with substantial knowledge in e-motorcycle building and its intricacies to guide me.

Have you built a smaller scale ebike before? How's your knowledge and experience in welding? What battery welding equipment do you have? CAD? Etc, etc, etc.

There's a LOT that goes into making something as fast and powerful as you are talking about, especially when you seem to aim to build even the frame yourself. Starting with simpler parts and pieces and working your way up to it would be wise.

Jumping into the deep end of "I'm going to replicate surron's from scratch!" is an extremely ambitious goal... you should temper your expectations.

 

[Rhapsody]

Have you built a smaller scale ebike before? How's your knowledge and experience in welding? What battery welding equipment do you have? CAD? Etc, etc, etc.

There's a LOT that goes into making something as fast and powerful as you are talking about, especially when you seem to aim to build even the frame yourself. Starting with simpler parts and pieces and working your way up to it would be wise.

Jumping into the deep end of "I'm going to replicate surron's from scratch!" is an extremely ambitious goal... you should temper your expectations.

To be honest this is the first ebike I going to be building. I know aiming to replicate a surron seems ambitious... The truth is I want to build an ebike that somewhat looks like a surron with a 48v 20ah battery, motor and controller of equal standards and the ability to get a distance of at least 40km out of it. If you can help I would really appreciate. Also I would be building the battery myself, I have access to a spot welder, nickel strips, 18650 cells, a bms... whatever I will need to complete the task.

 

[chuyskywalker]

Go to youtube, my man, or browse the build threads here. There's AMPLE amounts of how-to's out there already without people needing to hold your specific hand to start this. When you get stuck and research fails you, come back and asks specific questions, demonstrate that you've done some/any leg work on solving it yourself, and people here will be happy to help.

 

[Rhapsody]

Go to youtube, my man, or browse the build threads here. There's AMPLE amounts of how-to's out there already without people needing to hold your specific hand to start this. When you get stuck and research fails you, come back and asks specific questions, demonstrate that you've done some/any leg work on solving it yourself, and people here will be happy to help.

Understood thanks for the help.

 

[e-beach]

Get your motor, your wheels and build your battery. Once you have those components, build your frame around them. It will be easier to build a frame around components you can measure then it is to theorize measurements of components you don't have yet.

 

[TPEHAK]

You need to design whole thing in CAD program first.

Here is how you build the frame

Motor controller for reference design with pedal assist function can be taken here

Archon X1 Programming Thread (questions and experiences)

I played around a little bit and was finally able to connect via VESC Tool to my Innotrace X1! First I made connection using a simple USB to CAN adapter (e.g. canable) and tried to send common VESC CAN commands (VESC CAN-Bus Communication). I got no response and assumed it has been either...

forums.electricbikereview.com

Reference firmware for motor controller can be taken here

vedderb - Overview

vedderb has 38 repositories available. Follow their code on GitHub.

github.com

Here how to make brushless motor

Here is how to build battery

https://www.emtbforums.com/threads/tqfreaks-dengfu-e55-build-thread.32525/post-480116

 

[bananu7]

an ebike that somewhat looks like a surron with a 48v 20ah battery, motor and controller of equal standards

There's zero chance you'll be able to match Surron's quality with those components if you go DIY. Same goes for the frame if you make it from "steel tubing". Your "document" is a wishlist, not a plan.

problem is I need someone with substantial knowledge in e-motorcycle building and its intricacies to guide me

How much are you paying for consulting? Or are you assuming you'll get professional quality consulting by paying substandard prices? The Surron bikes (which you're comparing yourself to) were designed by a large team of people over the course of years, working on every single detail. How much do you think designing it costed?

Now, I don't want to sound too discouraging, but you're heavily underestimating the project right now. That's not uncommon for a first-time builder and happens to all of us, myself included. At least you're using existing wheels, controller and motor. That's a good start and will give you something to build "against". So let's review what we have in there:

* If you want to build on 19" wheels, you'll end up with a teenager-sized vehicle at most (kind of like the Surron). Make sure you're aware of it. I would really recommend going with a 21" up front for a full-sized adult.

* 1-2kW motor is far too weak for this, unless you're citing the "rated" power. The actual system power you should target for this build should be around 7.5kW +/- 2.5kW. Less than that and it will just struggle to move around. More than that and you'd need to heavily upsize all components making the build impractical compared to an MX frame.

If you want it to go offroad, mid drive is the only option. Hubs are only OK for the pavement or gravel roads. And in that case, you'll probably want QS165 with either the surron reduction mid-hub (you can actually buy them on Aliexpress) or the built-in reduction.

* 60V is unnecessarily low. 72V controllers are cheap enough to go with 20s.

* 200mm fork travel is enough for a kids bike or for use on gravel roads. It's not enough for serious offroading for an adult. At the same time I understand that you'll be fighting for every gram. Realistically, your options are either a 200m FastAce fork (37mm) or a used KTM Freeride front-end (43mm). I know that Surron riders praise the Freeride fork as a massive upgrade; for me it was absolute garbage compared to the full-sized 300mm travel WP Xplor.

* Don't pick the shock spring rate until you know the total weight and weight distribution. Don't pick the shock length until you know what rocker system you want to use and how much progression you will need. Builds without a rocker aren't appropriate for offroad.

* 203mm rotors are fine for a bicycle. Brakes should be picked after the total weight of the vehicle is known.

So even at the component choices you have a few things to think about. You should probably decide on a weight budget ("lightweight" means absolutely nothing) and see how much you can "spend" on what parts.