Very Noisy Bafang SWX Front Hub Motor

[Tubamanandy]

I spotted the other thread about a noisy rear motor with a possible sticking clutch.

My front hub Bafang SWX (250 Watt) has been very noisy for a while now and there`s obviously a problem with it. When you ride it the power seems absolutely fine but it sounds like an aircraft taking off from low to high revs. Also, when you spin the front wheel you can almost feel and count every notch of the gears. I`m sure it didnt used to be like this. The gears feel like they are permanent engaged yet surely this motor must have some sort of clutch mechanism for freewheeling ?

Are there any pictures of the inside of this very popular and good motor and where do you get spares for it ? Do you think it is a clutch issue or something worse ? It is still very fast & powerful just incredibly noisy with alot of drag.

Really could do with an expert on this one.

 

[Deleted member 4366]

It's not a clutch problem causing the noise. You can check whether your clutch is working by rotating the wheel backwards and forwards with your hand and the wheel in the air. Backwards, it will turn the motor through the gears, so quite a bit of resistance; forwards, the clutch should disengage, so the wheel should turn freely.

Did you increase the current at all, which will make the motor noisy, or did you change the controller?

If the noise feels like pulsing/notching, a sinewave controller will make it a lot smoother and quieter. If the noise is more continuous, it could be worn bearings or water inside has made it rusty.

As the gears are cheap, and to eliminate the possibility of worn gears, you could get a new clutch and gear assembly from BMSBattery, and get a S06S plus LCD and sensors at the same time. Then, it should be nice and quiet.

 

[Tubamanandy]

Ok Dave almost nailed this one !

Just been out to the bike and lifted the front wheel. It freewheels very easily now forwards and backwards. It was NOTHING like this in the afternoon after a ride so surely clutch wasnt fully detaching this afternoon ?

I wonder if its a build up of heat issue ?

Where do you order parts for these motors ? Still has loads of power so dont think its a goner just yet.

 

[Deleted member 4366]

You can get the clutch and gears from Woosh, or you could take the opportunity to upgrade your controller, in which case get the controller and clutch from BMSBattery.com

 

[Tubamanandy]

Interesting development, went out to bike this morning and front wheel very freewheeling. Took it on 6 mile run to work & power fine, by time it had got to work and spun front wheel (when off the ground) felt like all the gears were permanently engaged again ! Exactly same happened on my ride home.

I still think if the motor has some form of clutch then its a clutch issue as its not always disengaging.

If I order the parts, are they easy to fit on this motor and do you need any special tools or experience ?

 

[Deleted member 4366]

Show us a picture of your motor, and it'll be easier to advise. Some are dead easy, others are nigh on impossible. When the clutch sticks, you can free it off by whacking the wheel in the forward direction.. Sometimes jumping off the curb or a little bunny hop will do it.

 

[Tubamanandy]

Here is my Bafang motor with the dodgy Clutch (it frees itself off overnight and next morning its like there is nothing wrong). By time I`ve rode it to work (5.5 miles) and back, clutch is well and truly on all the time and loads of resistance. It`s fine by next morning but I need to sort this out - new clutch mechanism or oil/grease existing one ?

 

[Deleted member 4366]

Those motors are dead simple to disassemble. Take the screws out from the side with the wire coming out, then tap the axle on the other side to remove the core. To remove the other side-plate is a bit more difficult. You have to support it, while you tap the axle without damaging the wire, and be ready to catch the core as it drops. The clutch slides off the axle, where it sits on a key-way. Sometimes they're retained by a circlip.

 

[Tubamanandy]

Thanks for the info - just waiting to hear from Woosh now re the parts