eBike Rear Hub - Clicking Noise

[portals]

My rear hub has stated to make a kind of random clicking noise, I've not been able to identify where it's coming from yet and am a little concerned and want to understand what it is and fix it before taking bike out again.

You can hear it in first few secs of this video, anyone any ideas?

(I'm not Tam btw, this is a smurf account for privacy)

 

[saneagle]

You didn't show enough to make a proper diagnosis. If the noise is definitely from the motor, the only thing it's likely to be is a detached magnet.

 

[portals]

Thanks

Difficult to get decent audio on a phone, got my son to record this, a little better.

If something is loose like a magnet wouldn't it make a noise all the time (as it's loose)?

It also appears to be getting noisier.

 

[portals]

When I spin it for second time you can quite clearly (if you turn up audio) hear the clicks at 3->6 secs and again at 20->21 secs.

 

[Sturmey]

The freewheel give a little kick in the second video. I would take the chain off or tie it up off the freewheel or whatever so that the complete freewheel spins with the motor when you check again. This would indicate if the fault is in the freewheel or not.

 

[portals]

Thanks. It's only done the little kick a cpl times but yes I'll take off chain and see what happens, it sounds as if whatever the issue is is getting slowly worse.

I'd like to try and at least identify if it could be a rear hub issue or what I was hoping is that it's a rear drive train issue as local bike guy will help with that.

 

[saneagle]

Thanks. It's only done the little kick a cpl times but yes I'll take off chain and see what happens, it sounds as if whatever the issue is is getting slowly worse.

I'd like to try and at least identify if it could be a rear hub issue or what I was hoping is that it's a rear drive train issue as local bike guy will help with that.

Use the pedals to turn the motor. If the click goes away.it's the freewheel. If it doesn't, it's the motor.

 

[portals]

Used the pedals to turn the motor with battery off and click is still there I think.

Why does that indicate it's the motor, if it was the freewheel wouldn't it still click too?

 

[saneagle]

Used the pedals to turn the motor with battery off and click is still there I think.

Why does that indicate it's the motor, if it was the freewheel wouldn't it still click too?

Either the clicking is there or it isn't. You need to determine which it is. Only check the clicking when the pedals are turning the motor, not when it's freewheeling. The clicking is obvious when you use the power to turn the motor, so it should also be obvios when you use the pedals too.

 

[portals]

It's harder than you think to manually move a pedal to get the bike up to speed, it starts shaking around like mad in the stand...

I believe it is clicking yes when turning by hand, still confused as to why this eliminates something in the drive train (that has given me more hassle than anything else in the build)?

The freewheel give a little kick in the second video. I would take the chain off or tie it up off the freewheel or whatever so that the complete freewheel spins with the motor when you check again. This would indicate if the fault is in the freewheel or not.

Just tried that, not easy without removing chain, got missus to help hold it out of way and yes it still clicks.

 

[portals]

Are you saying that one of these magnets could be loose and causing the noise?

If so what is the fix?

Is it safe or unsafe to use in meantime? (I'm way more paranoid about dropout spin out than knackering the motor)

thanks

 

[portals]

I made another video, you can hear the clicking at 7-9secs and other strange noises at 14-18secs.

I think it is the motor...help!

 

[saneagle]

Are you saying that one of these magnets could be loose and causing the noise?

If so what is the fix?

Is it safe or unsafe to use in meantime? (I'm way more paranoid about dropout spin out than knackering the motor)

thanks

View attachment 52553

Where you show the arrow saying loose magnet is the stator. the magnets are glue to the inside of the hub, which is the black thing with shiny magnets on the inside. What can happen is that when the stator is put into the hub, it goes a little crooked and it catches on a magnet as it goes in and chips a magnet so that a piece of detatched magnet gets stuck to the stator and grinds on the rotor (hub) as it rotates. the piece of magnet can move if it's small, so the sound changes from time to time. a completely detatched magnet would make more of a grinding noise.

As you can see, there isn't really anything inside that can cayse clicking other than a bit of debris or maybe a badly positioned wire touching the side-plate.

Nothing in the freewheel moves when it's turning at the same speed as the motor, which is why you need to test by pedalling. if nothing is moving, nothing can click, but when the frewheel is freewheeling, you can get sticky pawles that click from time to time. As you don't seem to be able to test that, why not pour a load of 3 in One oil down the axle into the freewheel to see if the clicking goes away. Your video shows that it needs oiling anyway unless you have insufficient sapce behind it so that it's catching on the motor or you have debris between the back of the freewheel and the motor.

 

[portals]

Appreciate the response.

I made this earlier but forgot to post, this is me manually operating pedals by hand with battery off.

Clicks at 9-12 secs, louder click at 18 secs.

Does this shed any more light?

Shop I bought kit from from thinks it's freewheel but he hasn't told my why yet, loose debris does make more sense to me with the noise.

It didn't do this first year of use though so the debris has worked loose recently, maybe when I fell over stationary on bike few weeks ago, possible hub got knocked then so loosened debris?

thanks

 

[saneagle]

Do the easy thing first. Get some 3 in One oil into the freewheel and clean out behind the freewheel with a cloth held edge ways dipped in paraffin or petrol. If that doesn't get rid of the noise, it might be worth opening the motor to clean it out, but it's possible to chip a magnet when it springs back together.

 

[portals]

I have some 3-in-1 oil so will give that a go although I did oil it other day, obviously I'm not using enough if you spotted it being dry

No paraffin or petrol in but do have 5l gerry can of 99.9% Isopropyl alcohol (IPA), will try that.

 

[portals]

Clicking is getting worse, you can hear it most of the way through this video and a few louder ones too.

Both sides of drive train look clean to me, it's never done off road and spent only 10mins in quite light rain maybe month ago.

 

[portals]

Thanks

I've put loads of 3-1 oil in, I tried to put in a lot using the flat bit ox axle where there is a slight gap, is this where I'm supposed to oil (pic below)? Also did the obvious bits where it spins and chain.

Get the clicking using throttle and also when battery is off when cranking pedals by hand.

I'm still none the wiser as to whether or not it's the drive train OR the motor

 

[saneagle]

That should go in OK from there. The back looks fine. No dirt or debris in there.

 

[portals]

I don't particularly want to take off rear hub as it took at least three visits last summer to LBS to get it secure, spacing correct in dropouts etc. and me trusting it not to spin out (hence the sharpie lines so I can see if axle nut moves a mm).

However I suppose there is little option now but to take it LBS and get his opinion on drive train vs motor.

He's not impressed (he didn't kick me out though...), with ebikes however he also didn't knock back the mechanical business...got a more than few bob off me in the end replacing parts too. I innocently mentioned amazon and he had a rant about buying stuff amazon then called them c**ts, think most bike guys are a little nuts...

If he confirms it's motor that'll be a fun Saturday job, watched a few YT videos of guys doing this on similar hubs to mine....doesn't look like much fun.

Will need to get a bearing puller from local screwfix or amazon.

They all complain about the motor wiring harness being very tight to get out when removing that side, is there a trick to this?

Any pointers/advice appreciated.

Thanks