An other Straight 8

An other Electra straight 8 build thread

I have 15 km of flat road from my house to my work here in the south of France. The aim was to design a comfy bike with a good chopper style.
I Chose the electra straight 8 for this project.




I started with a 16s8p battery pack with 18650GA cells / 60A BMS.









Then disassembled the bike



2 torque arms made with 5 mm stainless steel (one with holes for brake caliper mount)



The 9C RH205 motor was laced into the original rim with new red spokes.

The fork was first changed for a zoom one, but finally i chose the well known DNM USD-8. I had to change the front hub too for accomodating with the 20mm thru axle.

Brakes are Magura MT5e (for Regen). 200 mm Front disc and 180 rear.

The biggest work was to design the fiber glass battery box that fit in the frame.

That was my first experience with fiberglass. I made a wood master (Next time i will use PU...).





Then I made a two parts mould on the master :








And finally the battery box.






Electric system is :
- 12 FET Sine wave controller from Powervelocity.com
- 5k magura Throttle
- 12V DC converter for motorbike LED lights, flashers, horn and USB phone charger.
- Ignition key
- 3 positions switch
- XLR plug for the charger.


First ride :

Great battery box and cool looking chainring. 8)

Wow! Nice job. That battery box is awesome. Those front forks must make the ride a lot nicer. If the bounce is still too much a suspension seat post really helped on mine. Well done and very clean looking. Congrats.

Yes I'm seriously thinking about buying a suspension seat post.

Which one did you choose ?

Well done! Since you have a working mold, you might consider selling battery boxes for this frame?

Here are a couple more Straight-8's

https://www.electricbike.com/marks-cromotor-phatrod/