Chalo
100 TW
I finally took a few pictures of my cargo bike set up the way I use it. It started life as a 68cm, 27" wheeled Nishiki Rally road bike, but after using it in a couple of different pedal-only configurations, I decided to donate its rear triangle to my custom frame project. I made the part of the frame forward of the seat tube. It has a 20" front wheel and 700c rear wheel, with 2.0" and 35mm tires respectively.
I fitted a normal 48V 750W Bafang BBS02 with a 46t chainring, but swapped the crank arms for 152mm steel unicycle cranks. They're narrower than the stock arms because they don't flare outwards, and the short length lets me pedal at higher RPM to keep the motor spinning efficiently.
Here you can see the front platform, which I originally intended to carry a passenger seat, but which now carries a flip top tote bin on a thin birch plywood support. I set up the fork to take the drum brake "backwards", because the leading shoe is heavily worn in the forward direction and it works much better in reverse. The fork was a 20" BMX fork with 1" steer tube, but I welded a long 1-1/8" steer tube and crown race seat over it.
I attached the 48V 13.5Ah Shark battery using DMR clamp-on frame bosses and a piece of thin aluminum flat bar as reinforcement and a base for the 48VDC-12VDC converter. At the moment, there are only lights plugged into the voltage converter. Soon I'll install a 48V compatible taillight, and then I can remove the converter and its associated wiring (because the 3W headlights already accept 12-80V).
I use lockable brake levers to make the bike stable for parking, and for this reason I don't have switched levers. The rear brake is a BMX U-brake mounted on an adapter plate. It's very strong and has good progressive lever feel. In the picture, the brake is being applied by the locking lever.
You can see the unusual cassette arrangement, with five out of eight gears placed in the outer positions, and the other three tucked behind as spacers/spare parts. The chainline of this bike causes the chain to be noisy and to drop often when used with the three inner sprockets, so I locked the derailleur out of those gears.
I have electronically limited the controller to 25mph, but I rarely ride that fast. Unless I'm trying to make time getting someplace, I ride between 14 and 20mph. In that speed range, the bike handles well, and I usually have time to react to surface problems so I don't beat up my cargo (e.g. groceries) unnecessarily.
I split my transportation miles between this bike and a bunch of pedal bikes, but I've logged about 600 miles on this e-bike so far. I damaged the first chain by inadvertently shifting under power, and that's the one mechanical part I've replaced so far.
I bashed up my first headlights, which were LED strips attached to the front edge of the cargo platform, and replaced them with the 3W spots in these photos. I leaned the bike against its charging plug at one point, and had to replace the charger's coaxial connector and battery charge port to repair the damage. Those are the only electrical replacement parts so far.
As for future improvements, I'd like to make a fork with more tire clearance, shorter axle-to-crown height, and longer offset to better match the very slack 68 degree head angle. I'd also like to try a 26 inch rear wheel to lower the bottom bracket height and gearing range a little bit.
I fitted a normal 48V 750W Bafang BBS02 with a 46t chainring, but swapped the crank arms for 152mm steel unicycle cranks. They're narrower than the stock arms because they don't flare outwards, and the short length lets me pedal at higher RPM to keep the motor spinning efficiently.
Here you can see the front platform, which I originally intended to carry a passenger seat, but which now carries a flip top tote bin on a thin birch plywood support. I set up the fork to take the drum brake "backwards", because the leading shoe is heavily worn in the forward direction and it works much better in reverse. The fork was a 20" BMX fork with 1" steer tube, but I welded a long 1-1/8" steer tube and crown race seat over it.
I attached the 48V 13.5Ah Shark battery using DMR clamp-on frame bosses and a piece of thin aluminum flat bar as reinforcement and a base for the 48VDC-12VDC converter. At the moment, there are only lights plugged into the voltage converter. Soon I'll install a 48V compatible taillight, and then I can remove the converter and its associated wiring (because the 3W headlights already accept 12-80V).
I use lockable brake levers to make the bike stable for parking, and for this reason I don't have switched levers. The rear brake is a BMX U-brake mounted on an adapter plate. It's very strong and has good progressive lever feel. In the picture, the brake is being applied by the locking lever.
You can see the unusual cassette arrangement, with five out of eight gears placed in the outer positions, and the other three tucked behind as spacers/spare parts. The chainline of this bike causes the chain to be noisy and to drop often when used with the three inner sprockets, so I locked the derailleur out of those gears.
I have electronically limited the controller to 25mph, but I rarely ride that fast. Unless I'm trying to make time getting someplace, I ride between 14 and 20mph. In that speed range, the bike handles well, and I usually have time to react to surface problems so I don't beat up my cargo (e.g. groceries) unnecessarily.
I split my transportation miles between this bike and a bunch of pedal bikes, but I've logged about 600 miles on this e-bike so far. I damaged the first chain by inadvertently shifting under power, and that's the one mechanical part I've replaced so far.
I bashed up my first headlights, which were LED strips attached to the front edge of the cargo platform, and replaced them with the 3W spots in these photos. I leaned the bike against its charging plug at one point, and had to replace the charger's coaxial connector and battery charge port to repair the damage. Those are the only electrical replacement parts so far.
As for future improvements, I'd like to make a fork with more tire clearance, shorter axle-to-crown height, and longer offset to better match the very slack 68 degree head angle. I'd also like to try a 26 inch rear wheel to lower the bottom bracket height and gearing range a little bit.