Voilamart mystery

[Ezrider_028]

Voilamart 1000w rear motor w/1000w controller and 48v 20ah battery.

Condition 1 : when approximating the top speed of 30ish MPH, I hear a rubbing sound similar to the wheel hitting the frame but I inspected the wheel and even switched the kit to a different bike and same result - so it seems to be motor related. The SW900 generated error 9 but then it went away.

Condition 2 : To continue my trouble shooting I ordered the larger1500w controller and a 52v 30ah battery to see if the controller was the issue - hence I tested both controllers with the bike on the stand and there is no rubbing sound with No Load, so seems it only happens when I ride.

But an interesting find is that the 1000w controller had a higher top speed (no load) of 42MPH compared to the 1500w controller 40MPH (also no load), so puzzles me why.

The only thing that I can think of is that I did shunt mod both controllers and maybe I added more solder to the 1000w ?

Any Thoughts on these 2 scenarios are appreciated ?

 

[neptronix]

Do you hear the rubbing sound when the power is on? if so i'm thinking bearing sound or rubbing brakes.. what else could it be.
Top speed differences of 2mph per controller isn't super unusual.

Do you have a screen for monitoring the watts/amps/volts and MPH of your bike? if not, it's a great diagnostic tool for things like this.

 

[Ezrider_028]

Thanks for the prompt response. I forgot to mention that initially I thought it might be bearings so I replaced the freewheel and even did some grease maintenance on the bottom bracket with new bearings and even a new derailleur. But as stated the issue only happens intermittently either when I initially take off using the throttle or when exceeding 28MPH, else there is no issue. No tool other than the SW900 showing watts, speed, and the e-bike tester. I will keep fiddling to see if I can find the root cause.

As far as the speed, I had seen that upgrading the controller from 1000w 26amp to 1500w 35amp would result in a few miles faster performance. So was a bit disappointed that the little 1000w guy is beating the larger 1500w controller.

 

[neptronix]

Yeah your hub motor bearings might be your problem.
How old is the motor?

 

[Ezrider_028]

Its coming up to 2 years now. I’ve never opened a hub motor so will have to educate myself a bit. I don’t think there are repair shops for these (not sure).