grindz145
1 MW
So I've been doing this whole Electracycle thing for a while now, and it owns. I love my ebike. I love having 3kwh at my disposal. I love that I can load 60 lbs of gear without batting an eye, and I love real acceleration.
However, what I have with that bike (as most of us do) is a fast electric moped. You really wouldn't want to pedal it for much more than a block or two without power.
So that is the motivation for this build; to build a bike that it pedalable as a decent road-bike by itself, but with assist. I'm inspired by AJs commuter booster friction drive, and other lightweight builds. So I decided to do a build with a small geared hubmotor.
Specs:
-Trek 1.2 with Carbon fork
-Cute Q100 rear hubmotor (~4lbs)
-Lyen mini-monster 6FET sensorless controller
-20s 5ah nanotech lipo (in backpack)
-Surly Adventurer rear rim
-9 speed freewheel
-clipless pedals
-Old school cycle analyst
-cheap Chinese brakes
-Potentiometer "knob" throttle
-Brooks Saddle
Yes, that's the throttle...for now...
The main technical motivation for this bike was to build a bike which would current limit fairly low (maybe 10-15A), but will continue to provide assist up to 30mph. This way as the voltage goes up and the current stays limited, the effect will be linearly more power as the rider pedals faster.
So I had to use a potentiometer as the throttle to start off with, because the bars are too wide and I couldn't come up with a decent way to mount them on drop bars (suggestions appreciated). Right now I'm thinking about using some other type of pot, and an old road downtube road shift lever to adjust the throttle. Since it's going to be more or less binary, I don't have to worry about modulation too much, but I shouldn't have to hold the throttle down.
Performance:
I haven't set up current limit yet, so it really isn't set up the way I play to, but let me tell you, the Q100 is capable of about 1000w for short periods of time. The thing took off and accelerated hard up to 30mph. The nylon gears will not put up with this for very long I can't imagine...
Issues:
Right now the sensorless controller is giving me grief. If I try to accelerate (give it throttle) from 4mph to 12mph it looses sync and starts making some horrible noises. After 12mph (If I pedal up to 12mph first) and then accelerate, the controller has no problem. I suspect this is EMI getting on to the non-powered phase widings and confusing the controller. Anyone else had similar issues? I'm going to try winding the phase wires differently and see what happens.
Future Plans:
-Finely calibrate Cycle Analyst
-Limit current to 10A
-Fix the damn sensorless Sync issue
-Find better throttle setup
-Find the "sweet spot" where I can get 20 miles per charge or about 19wh/mile
All in all so far, the bike is quite pedalable on it's own. I wouldn't hesistate to ride it 20 miles, leaving the backpack and the batteries at home. I haven't weight it yet, but I imagine the bike itself is well under 30 lbs. The original bike was around 21. It feels a bit heavier in the rear, but surprisingly not terribly so.
However, what I have with that bike (as most of us do) is a fast electric moped. You really wouldn't want to pedal it for much more than a block or two without power.
So that is the motivation for this build; to build a bike that it pedalable as a decent road-bike by itself, but with assist. I'm inspired by AJs commuter booster friction drive, and other lightweight builds. So I decided to do a build with a small geared hubmotor.
Specs:
-Trek 1.2 with Carbon fork
-Cute Q100 rear hubmotor (~4lbs)
-Lyen mini-monster 6FET sensorless controller
-20s 5ah nanotech lipo (in backpack)
-Surly Adventurer rear rim
-9 speed freewheel
-clipless pedals
-Old school cycle analyst
-cheap Chinese brakes
-Potentiometer "knob" throttle
-Brooks Saddle
Yes, that's the throttle...for now...
The main technical motivation for this bike was to build a bike which would current limit fairly low (maybe 10-15A), but will continue to provide assist up to 30mph. This way as the voltage goes up and the current stays limited, the effect will be linearly more power as the rider pedals faster.
So I had to use a potentiometer as the throttle to start off with, because the bars are too wide and I couldn't come up with a decent way to mount them on drop bars (suggestions appreciated). Right now I'm thinking about using some other type of pot, and an old road downtube road shift lever to adjust the throttle. Since it's going to be more or less binary, I don't have to worry about modulation too much, but I shouldn't have to hold the throttle down.
Performance:
I haven't set up current limit yet, so it really isn't set up the way I play to, but let me tell you, the Q100 is capable of about 1000w for short periods of time. The thing took off and accelerated hard up to 30mph. The nylon gears will not put up with this for very long I can't imagine...
Issues:
Right now the sensorless controller is giving me grief. If I try to accelerate (give it throttle) from 4mph to 12mph it looses sync and starts making some horrible noises. After 12mph (If I pedal up to 12mph first) and then accelerate, the controller has no problem. I suspect this is EMI getting on to the non-powered phase widings and confusing the controller. Anyone else had similar issues? I'm going to try winding the phase wires differently and see what happens.
Future Plans:
-Finely calibrate Cycle Analyst
-Limit current to 10A
-Fix the damn sensorless Sync issue
-Find better throttle setup
-Find the "sweet spot" where I can get 20 miles per charge or about 19wh/mile
All in all so far, the bike is quite pedalable on it's own. I wouldn't hesistate to ride it 20 miles, leaving the backpack and the batteries at home. I haven't weight it yet, but I imagine the bike itself is well under 30 lbs. The original bike was around 21. It feels a bit heavier in the rear, but surprisingly not terribly so.