Loud noise from rear mech when I stop pedalling
bing gordon
Posts: 662
I was out today for a ride and 20 miles in I got this almighty noise like noisey worn brakes but it's not the brakes , it was coming from the rear mech. It seemed to start when I moved the pedals backwards say 1/2 a turn just to adjust my leg & feet position.
When I got home I threw it up on the stands and adjusted the rear mech to the high hilt but when I spin the pedals then stop pedalling it can suddenly start again, not every time it tends to be in low gears. It's like the jockey wheel is out of line and the teeth dont line up but it's vertical and in line.
Anyone had this before and were's the problem lie ? mech or rear the hub ?
When I got home I threw it up on the stands and adjusted the rear mech to the high hilt but when I spin the pedals then stop pedalling it can suddenly start again, not every time it tends to be in low gears. It's like the jockey wheel is out of line and the teeth dont line up but it's vertical and in line.
Anyone had this before and were's the problem lie ? mech or rear the hub ?
0
Comments
-
Must be the hub. If you think about it, when you stop pedalling the entire drivetrain stops - chain, cassette jockey wheels etc. It wont be any of those components making a noise.
I'd suggest it's the freehub.0 -
Are your wheels Mavic by any chance.
Reason I ask is that there is a phenomenon known as the Mavic "death squeal" which occurs when the freehub bearings are shot and need replacing.
See this thread as an example of the problem
viewtopic.php?f=40004&t=13035971&p=19702001&hilit=mavic+death#p197020010 -
Yeah their Mavic's , I will strip the freehub down and take a look tomorrow and get back , thanks for sourcing out those vid's0
-
I'm only in work later on so I thought I have a go before I trek off. I have stripped the freehub down and it was gunked up, not really bad but bad enough to think it might cause a problem. The bearings are fine and the plastic part of the freehub isn't worn down.
I was going to rebuild it then I realised I've no mineral oil. It might be a stupid question but can I use DOT 5.1 mtb brake fluid rather than treking off out to a store in heavy traffic. I also have spray grease lube0 -
It really needs a light mineral oil for the pawls, and for the plastic bushing that is almost certainly the source of your racket. You might get away with dry pawls and a dollop of grease on the bushing for a day until you can buy some oil.
No idea about DOT4 brake fluid. I know it's reputed to strip paint, so I probably wouldn't want it in a freehub0 -
OK thanks , I used a couple of drops of crivit chain oil just for now till I get some mineral oil. I have rebuilt it using the correct spacers for the the cassette and there seems to be abit of play in the hub. It's all tight and I would say the cassette is moving , not up and down but rocking ever so slight left & right about 1mm. Is this acceptable or is it freehub replacement time ? or can you just buy the plastic bush for the freehub and replace that. The freehub itself and bearings are fine.0
-
Oh and I just dropped on this, this is exactly the same problem I have
https://www.youtube.com/watch?v=DmgLe1vcq5I
I have stripped it down again and after a further inspection the bushing and teeth in the freehub look worn. I have decided to buy new one.
Are these the correct items , hub and oil :-
http://www.chainreactioncycles.com/mavic-freehub-body-ftsl-m11/rp-prod33442
and
http://www.chainreactioncycles.com/weldtite-tf2-cycle-oil/rp-prod5955
The oil was the cheapest of a few mineral oils I found on chain reaction. I'm using them for their next day delivery as I need the bike for the weekend0 -
I Ordered a new freehub from chain reaction;-
http://www.chainreactioncycles.com/mavic-freehub-body-ftsl-m11/rp-prod33442
and installed it today following this guide
https://www.youtube.com/watch?v=CROJ5sLk8-Y
Using the new spacer and the correct oil. Plus I used a mavic hub spacer for the cassette along with a shimano 1mm spacer and I snuged it up without over tightening.
Can someone please tell me if there should be any play like a slight rocking motion coming from the cassette ? I don't mean up and down , I mean left to right ? mine still rocks slightly as though it's loose but the cassette is tight enough downwards. The reason I ask is , I don't want the new freehub bushing wearing away in weeks rather than months/years due to left/right movement that shouldn't be there.0 -
I don't think there should be any side-to side play in the cassette. Is it just the cassette moving ... if it is then I'd check that you've seated the 11/12T cog on the end of the freehub correctly. It only just engages the splines on the freehub, and it's ever so easy to think you've got it right but it's not engaged. Then when you're tightening it what you're effectively doing is just tightening the 11/12T cog an nothing more.I Ordered a new freehub from chain reaction;-
http://www.chainreactioncycles.com/mavic-freehub-body-ftsl-m11/rp-prod33442
and installed it today following this guide
https://www.youtube.com/watch?v=CROJ5sLk8-Y
Using the new spacer and the correct oil. Plus I used a mavic hub spacer for the cassette along with a shimano 1mm spacer and I snuged it up without over tightening.
Can someone please tell me if there should be any play like a slight rocking motion coming from the cassette ? I don't mean up and down , I mean left to right ? mine still rocks slightly as though it's loose but the cassette is tight enough downwards. The reason I ask is , I don't want the new freehub bushing wearing away in weeks rather than months/years due to left/right movement that shouldn't be there.0 -
this is wrecking my head. I have stripped it down , tried it with the mavic spacer on the freehub on it's own , got worse. I added the shimano spacer 1mm job and still play. I then added another shimano 1mm and still playmadness. If I hold the wheel up I can see movement. ever so slight but movement.
the cassette is months old bought new a 6700 11-28t0 -
-
Is the cassette moving or the freehub body?
Or perhaps play in the bearings that wasn't noticed before the freehub work? I haven't adjusted bearing tension on a Mavic but Shimano/Campag wheels can be sorted with a quick tweak.
I once had some Aksiums and got the dreaded squeal of death from the freehub, didn't bother fixing it though as the rims were fairly worn. I suspect there are a few other folks out there with a worn but functional Aksium front wheel that just doesn't get used anymore and is being saved for some purpose...0 -
Looking at some photos the Mavic wheel uses industrial rolling element bearings pressed into the hub for the axle. The freehub body has a rolling element outboard bearing and a plain bush inboard bearing (yuk), which is what gives the trouble. End float of the freehub body is controlled by using a spacer that sits against the inner races of the bearings and a end cap screw to preload the stack.
Can't easily see a way that you would get a floating freehub body using this arrangement if correctly assembled; might you have cross-threaded the cassette lockring or the axle end cap?- - - - - - - - - -
On Strava.{/url}0
