First EV Build - 1983 Honda XR350R Conversion: 72V 3kW (Supermoto Project)

[83Xr250r]

Hey Yall
I’m converting a classic 1983 Honda XR350R over to an electric powertrain. I picked up this XR frame and decided it’s the perfect bike for for a street build.

Full disclosure: This is my very first EV build. I'm traditionally a gas bike guy I know my way around combustion engines and regular bikes inside and out, but I’m completely new to the electrical side of things. Honestly, I don't know a whole lot about battery layouts or controllers yet, but I want to learn

The switch is mainly cuz local police in my area have been cracking down hard on gas powered bikes lately, to the point where guys are getting them impounded. Thankfully, the cops around here don't really care as long as the bike is electric and it at least looks like you're pedaling. Because of that, the plan is to make this look clean and somewhat street legal.

Ultimately, my dream end-goal for this bike is to turn it into a full supermoto build. That said, street setups are hella expensive right nowespecially trying to lace up 17s. For now, I'll likely get the powertrain running on the stock dirt wheels to save some cash, and upgrade to the supermoto look down the line as funds

• Frame: 1983 Honda XR350R
• Voltage: 72V system

• Motor: 3000W continuous mid-drive setup. It features a Double-D (flat on two sides) output shaft, so I'll need to source or machine a compatible drive sprocket or an adapter that won't slip under load. I don't know exactly what brand or model the motor is. I got it from a friend, and he didn't know what it was either.

• Controller: 72V Sinewave controller. Same story as the motor came from a buddy with no brand labels or instruction manual, but I'm glad it's a sinewave setup so it should run incredibly quiet and smooth once it's wired right.

• Battery: 72V triangle e-bike battery. The brand on the casing says Codd Power, but that's all I know about it I don't have a spec sheet or know its exact history. I'm planning around a tight 3.75-inch thickness. I'll post some detailed pictures of everything below once I start the mock-up so hopefully someone here can help me identify the whole kit!

• Gearing: Custom rear sprocket conversion (maintaining 520 chain if possible, or converting to a 420 setup depending on motor sprocket options)

I still want to run a solid headlight and basic lights to blend in properly on the street hopefully 4x3 so it will fit the stock housing . To keep things simple and completely isolated from the main 72V traction pack, I’m thinking about using a DeWalt 20V power tool battery adapter paired with a 12V step-down regulator/buck converter. I already have tool batteries lying around.

Since I am an electric beginner, I am completely open to all the advice, constructive criticism, and pointers you guys can throw my way. If anyone recognizes this motor, the sinewave controller, or has experience with Codd Power triangle batteries or has advice on the best place to get sprockets for a double-D shaft setup Thank yall

 

[vijaypanwar]

What controller are you actually using? What are the specs?

 

[vijaypanwar]

have you seen shadowsabre 12 fet controller . i think that controller is perfect for you giving you power upto 27kw.

 

[bananu7]

I don't know exactly what brand or model the motor is.

Same story as the motor came from a buddy with no brand labels or instruction manual,

I don't have a spec sheet or know its exact history.

Were all those parts confirmed to work together correctly? Or are they just random bits you managed to assemble together? If the latter, I would seriously question whether they form a reasonable base for a first build. A controller without manual, not configured for the specific motor already, is worth about as much as a brick of the same size. Even with a manual, there's no guarantee that it would actually mesh well with that specific motor; being "sine wave" won't have much to do with anything. With no software, diagnosis and tuning will be extremely hard as well, and rely entirely on what's already programmed.

A 3kW continuous motor might be a good fit power-wise, but does it have a reduction gearbox? Without one, you'll need to run extremely low gearing (perhaps less so for the street use, but SM still needs acceleration and low-end torque) and you'll compromise the driven sprocket location, hindering the suspension performance.

A battery of unknown origin and specs shouldn't be considered safe to be used for a high-performance motorcycle. You won't know if it has sufficient protection inside and whether it can handle the power ("e-bike battery"? unlikely...) and the abuse of motorcycle riding safely. I would highly discourage you from just throwing this onto the project unless you have the skill and expertise, or know someone who has, to check and verify that it's actually fit for the purpose.

I'll need to source or machine a compatible drive sprocket

Machining a custom sprocket for a weirdly dimensioned shaft will cost (street price) half as much as a new QS motor from Aliexpress with a sprocket already on it.

My advice would be to put all those parts in a bin for later use once you have more experience, pick up a medium power motor+controller combo from Ali, and (if you want to save money) spend 80% of your research and build time learning how to construct a safe battery pack, because that's where you can save the most on DIY - but also where proper knowledge and safety precautions are the most critical.