B20 electric bike , new motor problem

[Alex PAS]

Hello guys , sorry for but i need a little bit of help if is possible as i'm not very good at e bikes .
I bough a Electric bike Windgo B20 long time a go , i change the motor from 250w old one to 350w new one . I fix all wires as i should i took it for a test and the bike seems to work more slow than before .
My battery is in the picture and my controller as well .
My question is , why a 350 w motor work more slow than the 250w ? And how i can solve this problem .
Thank you very much .

 

[amberwolf]

If the motor is not identical to the old one, the controller may not drive it the same.

If the new motor has a lower kV (RPM/volt) than the old one, it will run slower for the same voltage. If it doesn't give it's k/V, it might give it's RPM at a certain battery voltage. If your old one also has this marking, you can compare them--if they're different, then that will be the difference in speeds.

If it's a sensored motor, it may have a different wire color combination than the old one did, so if your controller has a self-learn function that might fix that (or you may have to manually try different wire combinations until it works normally. There are various threads about phase/hall combo / combination / wire order that describe the process.


Also, if you upgraded the motor to get more power, that won't work without getting a "bigger" controller (along with any display needed for it, as the old one probably won't be compatible, and possibly other sensors like PAS, etc, and any other hardware that connects to the controller that might not be supported by the new one) that takes more battery current, and can convert that to more motor power.

That usually requires a bigger or better battery as well, so you wind up replacing most things on the bike...this makes it worth taking stock of what exactly you want out of the system, and figuring out ahead of time what power level/etc it will take to do that, so you can be sure you're buying the right stuff the first time.

If you need more details on that, I posted in another thread today in the last few hours with some explanations of that stuff for someone else.