
I recently completed this DIY electric motorcycle. Weighing in at 125 lbs this one-off prototype is super fun on tight and/or sweeping single track trails. As of this writing I have about 20 charge cycles on it and next steps are to make it street legal, improve the battery charging procedure, and to keep having fun riding it.
I sold my DRZ400S after doing the Trans America Trail and put those funds into this project. You can check out my trail blog at www.talesfromthetat.wordpress.com if you like.
I’m not the only one who thinks this is area of light weight electric motorcycles is an unfilled niche. Check out the French guys doing LMX and the Sur Ron bike from China too.

Stats:
- 7500 watts continuous (this is the output it will give all day without melting). That’s about 10 hp which doesn’t seem like much but since it’s electric it is a whole different world from a 10 hp gas motor. Another factor to consider with electric is that most motors will put out double their “continuous” rating for short bursts like 30 seconds (IF your batteries and controller allow). Regardless of the numbers there is a smile inducing sense of ample power. It wheelies with ease – at slower speeds. I do miss having a clutch.
- 52V – 30Ah battery. Cells are Samsung 30Q
- Kelly KEB72380 Controller
- Shimano Saint Brakes – I need to add a larger rotor to the back wheel but overall the brakes are excellent.
- CR125 seat
- YZ250 foot pegs
- 50″ wheel base (downhill bikes are in the 45″-50″ range and modern dirt bikes are around 58″)
- 35″ seat height (modern dirtbikes are generally 37″)
- 125 lbs. For reference: downhill bikes ~ 35 lb range, modern gas dirtbikes are at least 220 lbs
- 67 degree head hangle
- 13″ ground clearance (similar to modern dirt bikes)
- Front and rear suspension travel is 7″
- Range: so far I get about two hours of road riding or three hours on single track trails.

Here I have turned the smaller scale drawing of the frame into a full size on brown paper so that I could verify bend angles on the frame tubes.





One of the things I aimed for with this build was to minimize unsprung weight. This is a known key to maximized suspension handling. This photo compares rear tires from three bikes: at far right is a massive back tire from my CRF450X, in the middle is the one from my current electric motorcycle experiment, which weighs less than half that of the traditional motorcycle rear tire, and at left is the back tire from a Specialized Big Hit – downhill bike, essentially a 24″ bicycle tire.

Here I’m lacing up the rear wheel for my electric motorcycle experiment using a Pro Wheel 19X1.4 rim, Oset hub and custom SS spokes. For now I’m leaving the front wheel a regular 26″ downhill bicycle rim with Maxxis tire. If I end up doing the taco to it or going for DOT approval I’ll switch to something more like this for the front also.

Here the swing arm is being welded together. I used an air cooled Miller Econo-Tig.



