Hub motor making horrendous noise!

[LesleyA]

Been out for first time this year on bike today. Its a Synergie, I think I narrowed it down to a "Brio" model, but bought 2nd hand with no other details so not 100% sure.

It seems to have developed major drag from the motor wheel, whines even when pushing it with no motor engaged and when spinning wheel by hand. Did about 7 miles this afternoon, first half was OK, but then the noise started, and as I had no choice but to cycle back to where we had parked, I pressed on and it got worse. I can only describe is as like the hand wound air-raid sirens you see on wartime films, being wound very slowly. I'm assuming its hub related and also connected to the increased drag I am noticing. Is the hub serviceable or am I looking at replacement? As I guess its a brushed motor, would a strip down, clean and refit do any good? I have found some online hub strip guides and willing to give it a go myself, so any guidance or advice would be much appreciated.

 

[neptune]

In its present state, the motor is only fit for scrap. Therefore you have nothing much to lose by stripping it down. My guess would be a failed bearing. These are probably easy and cheap to replace.

 

[LesleyA]

Thanks for reply.

We were thinking possibly bearing related, so will open it up and have a look.

 

[halfer]

There's a few experts hereabouts who might be able to further advise if you post clear, high-res photos of the inside of the motor.

 

[LesleyA]

Thanks.

Its really odd as when we got home we didn't take bikes out of van straight away. Just got them out to put away and the wheel is running almost silently now, not as much drag either. To my untrained eye, that might still point to worn bearing, as now its cooled down its not binding as much, but guess I won't know for sure until we take it off and have a look.

 

[Deleted member 4366]

If it's a geared hub motor. The clutch was stuck. Can we have some photos of what you've got. That name doesn't mean anything.

 

[flecc]

I agree with d8veh, the clutch is sticking on. The motor is a brushed one that was in the Synergie Mistral rear wheel (Synergie taken over by Alien later).

This motor had a suspect clutch. Owners reported that on overrun down steep hills the bike would accelerate until about 25mph when drag would suddenly stop it going any faster, possibly the clutch re-engaging somehow.

 

[LesleyA]

Some shots of the the beast ... not exactly a thing of beauty and a joy to behold!

And views of the hub itself. If it is the clutch, how do I get at it and what needs doing to free it up? If you need anything closer or more specific, please let me know. Any advice much appreciated, thanks

 

[flecc]

I haven't opened one of these but seem to remember someone saying they open up on the left (brake) side. However, since you've said that problem has disappeared, indicating the clutch has freed, perhaps best to just carry on since it may never happen again. You won't be causing any harm by doing that.

 

[drsolly]

I've got one of those. Looking from the rear, one the left you have a drum brake.

The problem I had, was the internal gear/clutch assembly; the gears were ruined. A replacement was easy to fit, and cost me £13, including p&p. So if it is the clutch, and it goes more permanently, don't give up!

 

[LesleyA]

Thanks for replies. Rather than leave it and have the same problem next time we go out, we decided to investigate.

We opened up the hub yesterday, took out the motor with the planet gears still attached and powered it up and it is making a lot of noise considering its not actually driving anything. We haven't taken the gear assembly off the motor yet, there doesn't seem to be any excessive play and all teeth etc are good, no obvious wear or damage, so not actually sure what is causing it yet.

drsolly Where did you get your clutch parts from please?

 

[drsolly]

Wooshbikes in Southend. http://www.wooshbikes.co.uk

 

[LesleyA]

Thanks, will have a look

 

[trex]

Please post a picture of the inside of the motor for us to see where the problem may be.

 

[LesleyA]

Hi all and thanks for latest replies.

Was going to get some photos, but hubby had already started putting hub back together so too late! We stripped it down completely, and separated the 2 halves - rotor and stator I think they are called? Anyway, there was slight wear on one edge of the casing on the part without the magnets attached. When this was seated back with the magnet side, there was a few mm of lateral play on the housing where the axle bearing sits. This allowed enough movement for the edge of the non-magnet side to rub on the casing. Hubby put some Loctite retaining fluid around the bearing and reassembled so far. After allow it to sit for 24 hours he powered it up on the bench and it does sound as if the noise has gone. Even trying to flex the axle a little doesn't recreate it, so hoping its sorted.

We cannot understand why this "play" occurred as everything inside looks like brand new, all lubed where it should be and no sign of wear or damage other than the scruffed edge on the casing, so this must be a manufacturing tolerance problem. It isn't a big enough gap to shim it or even put a larger bearing in, but just enough to allow contact between the moving disk and the casing. Hopefully finishing the reassembly in time for the weekend to give it a proper try on the bike.

Hope this makes sense, sorry I didn't get photos in time, and hope you understand my "lay-woman's" terms above! Thanks for all who offered advice.

 

[bonerp]

i recently had a puncture and noticed that when I took the rear wheel out and refitted it, the spindle locknut mustve come slightly loose as I had an awful grating noise. Took the wheel out, nipped it up a little and it seems fine now. The was a very slight, almost unnoticeable amount of play in the wheel when fitted which made me think the locknut was too lose. Sorted now just by winding up a mm or 2.

 

[LesleyA]

Hi All,

Well our "repair" lasted for 2 successful outings - couldn't believe bike was so quiet - until this week when the problem recurred. Hub now stripped again and looks like exactly the same problem as before (detailed above). Now thinking might have to get a replacement hub. Seen these on eBay:

http://www.ebay.co.uk/itm/Electric-Rear-Wheel-Drive-Hub-Motor-36v-Volt-500w-Watt-Bicycle-E-Bike-Trike-Quad-/171388414463?pt=UK_SportGoods_CyclAcces_RL&hash=item27e78ba9ff

but they are brushless - obviously an improvement on my current brushed motor, but could anyone please advise if I need to replace the controller as well? My current controller is a Brush Intelligent Controller FGK312.

Also, anyone any thoughts on the hub listed above - I am only an occasional pleasure cyclist, so not facing daily use, and tends to be family friendly tracks and trails, so no excessive strain on it either! Thanks

 

[Deleted member 4366]

Yes, you need a new controller for a brushless motor. Can't you replace the bearings that are causing the free-play?

 

[LesleyA]

The bearing sits in a housing, and is very slightly loose - not enough clearance to fit a larger bearing, but just enough to allow movement. Hence the bearing sealant fix, which seemed to solve it, but hasn't lasted. Thinking of trying again with stronger bearing fit sealant.

I'll try to get some photos of the offending parts now its stripped again.

 

[Mike63]

Wooshbikes in Southend. http://www.wooshbikes.co.uk

If Woosh bikes can help you, look no further...100% reliable.

best of luck.....Mike