Using a powervelocity 15kW 120V controller with a 72V battery and MXUS 3k Turbo motor rated for 3kW continuous. I can comfortably reaching about 10kW peak.
Bike weights about 30kg.
She's.. umm... rapid! haha and range is pretty great!
At 30mph with no pedalling I predict approx. 35-40 miles.
Should get 20-25 miles of "hard riding" but brakes get hot quick as I've got no regen at the moment due to my investigation into a previous failure - details at the bottom.
The rough schematics (these changed a little but I ended up not updating the schematic and moved directly to wiring tables for the connectors):
Late stage CAD design with 3D scanned bicycle frame and 3D modelled battery, BMS, controller shelf, controller and contactor.
Ally frame fitting:
Battery pack post-welding:
For anyone in the know, yes all the cells had their internal resistance measured and matched in similar parallel blocks with the highest IR in the centre of the pack to reduce total heating in the pack - although this was an insignificant difference between parallel blocks. Oh and its 20s6p.
Battery pack with BMS attached:
BMS can handle 300A bursts, I have it programmed to cut at 150A and I have a hard fuse at 125A which has been well matched to the setup so far.
BMS software is pretty good actually:
Custom spoked wheel (by me) to the MXUS 3kW motor. (I learnt to spoke a wheel the same night I made it haha):
Almost finished product with the carbon side plate removed:
Changes made after this were the dash, wiring finished and big gel saddle.
The battery pack is yellow because it's wrapped in fire proof kevlar fabric.
Here is the 3D printed dash:
Note, the battery percentage is wrong, that's the only sh*t thing about the BMS software. But I know the percentage roughly based on cell voltage.
Some fun challenges:
The motor is so wide that I had to angle grind the 3mm ish thick logo plates off the casing so they didn't hit the brake calliper... (the calliper still grinds a little
)
Had to make a torque arm to transfer the motor torque from the dropouts (can be seen in above image of the bike side on) and instead into the swingarm of the bicycle. Without this the dropouts would just get ripped apart. There's similar torque in this to my GSXR 1000 according to my dyno print out (of the gsxr)
First and only "big" failure so far was at about 55mph when I lost all power and what had happened was a FET short circuited in one of the phases that required extensive open heart surgery to swap out that complete leg of MOSFETs. Since then it's limited to 30mph for range and reliability but I'll start turning up again soon. The worst outcome of this was that after the failure, the short circuit meant that the motor was cogging (dragging) so badly I couldn't even pedal. The first upgrade was adding a connector to disconnect the motor if this happens again so I can at least pedal.
The front flexes quite a lot under heavy braking and turning... I can't do too much about that... meh.
Regarding legality, it can be turned down a lot.
Feel free to ask questions.
Bike weights about 30kg.
She's.. umm... rapid! haha and range is pretty great!
At 30mph with no pedalling I predict approx. 35-40 miles.
Should get 20-25 miles of "hard riding" but brakes get hot quick as I've got no regen at the moment due to my investigation into a previous failure - details at the bottom.
The rough schematics (these changed a little but I ended up not updating the schematic and moved directly to wiring tables for the connectors):
Late stage CAD design with 3D scanned bicycle frame and 3D modelled battery, BMS, controller shelf, controller and contactor.
Ally frame fitting:
Battery pack post-welding:
For anyone in the know, yes all the cells had their internal resistance measured and matched in similar parallel blocks with the highest IR in the centre of the pack to reduce total heating in the pack - although this was an insignificant difference between parallel blocks. Oh and its 20s6p.
Battery pack with BMS attached:
BMS can handle 300A bursts, I have it programmed to cut at 150A and I have a hard fuse at 125A which has been well matched to the setup so far.
BMS software is pretty good actually:
Custom spoked wheel (by me) to the MXUS 3kW motor. (I learnt to spoke a wheel the same night I made it haha):
Almost finished product with the carbon side plate removed:
Changes made after this were the dash, wiring finished and big gel saddle.
The battery pack is yellow because it's wrapped in fire proof kevlar fabric.
Here is the 3D printed dash:
Note, the battery percentage is wrong, that's the only sh*t thing about the BMS software. But I know the percentage roughly based on cell voltage.
Some fun challenges:
The motor is so wide that I had to angle grind the 3mm ish thick logo plates off the casing so they didn't hit the brake calliper... (the calliper still grinds a little
)Had to make a torque arm to transfer the motor torque from the dropouts (can be seen in above image of the bike side on) and instead into the swingarm of the bicycle. Without this the dropouts would just get ripped apart. There's similar torque in this to my GSXR 1000 according to my dyno print out (of the gsxr)
First and only "big" failure so far was at about 55mph when I lost all power and what had happened was a FET short circuited in one of the phases that required extensive open heart surgery to swap out that complete leg of MOSFETs. Since then it's limited to 30mph for range and reliability but I'll start turning up again soon. The worst outcome of this was that after the failure, the short circuit meant that the motor was cogging (dragging) so badly I couldn't even pedal. The first upgrade was adding a connector to disconnect the motor if this happens again so I can at least pedal.
The front flexes quite a lot under heavy braking and turning... I can't do too much about that... meh.
Regarding legality, it can be turned down a lot.
Feel free to ask questions.
