hi I have a voodoo zobop e with a Bosch cx motor. At around 16-18mph there is a metallic rattle that appears to be coming from the motor. Above or below these speeds all sounds normal. It’s intermittent and doesn’t appear to affect performance. Halfords advised that this noise is normal and the motor engaging / disengaging. Has anyone else had this problem and is this normal?

Edited July 25, 20187 yr by Danpad

Metallic rattle suggests something is loose or vibrating.

 

I have the same motor, and no noise except once, when the chain guard worked loose and the resulting noise appeared to emanate from the motor.

Metallic rattle suggests something is loose or vibrating.

 

I have the same motor, and no noise except once, when the chain guard worked loose and the resulting noise appeared to emanate from the motor.

 

Thanks for the quick response, nothing appears to be loose on the bike or motor, always happens at the same speed. It sounds like a metal ring being spun round a pole if that makes sense. Trip to the dealer it is by the sounds of things. Thanks

check the lock ring that holds on the front sprocket as it can come loose.

 

check for any play in the motor bearings push and pull on the cranks for any play there should be none.

 

remove the peddles and cranks and grease the threads and replace.

 

check the indexing of the gears is spot on as the chain line on some frames are a bit hit and miss tho a loose front lock ring will also not help even if it is a tiny bit loose and the sprocket can move.

 

check that the mech hanger is also not bent as this can cause grinding in some gears where the chain line gets screwed up.

hi I have a voodoo zobop e with a Bosch cx motor. At around 16-18mph there is a metallic rattle that appears to be coming from the motor. Above or below these speeds all sounds normal. It’s intermittent and doesn’t appear to affect performance. Halfords advised that this noise is normal and the motor engaging / disengaging. Has anyone else had this problem and is this normal?

 

Halfords might be right in suggesting its something to do with an internal clutch engaging/disengaging at the cutoff speed, however they aren't right in saying its normal!

https://www.youtube.com/watch?v=SfN6d1xc_Qg

 

I’ve checked for play in the bearings and greased accordingly. Noise appears to occur even when not pedalling, always at the same speed. Checked brakes etc and they’re not rubbing. Noise appears to be coming from the motor.

https://www.youtube.com/watch?v=SfN6d1xc_Qg

 

I’ve checked for play in the bearings and greased accordingly. Noise appears to occur even when not pedalling, always at the same speed. Checked brakes etc and they’re not rubbing. Noise appears to be coming from the motor.

It can’t be the motor then as nothing is turning in the motor

Hub freewheel or hubs bearings are all that’s moving when freewheeling

sounds like a brake pad rubbing but check the spokes as a loose one sounds like that.

 

its def not the motor making that sound.

As I said before noise in that area can be deceiving. Check on a rack.

hi

i have exactly the same problem.

did you find a solution?

I have a Voodoo Bizango non Ebike that I bought several years ago and it makes this exact same noise - I could never figure out where it was coming from and Halfords insisted nothing was wrong