Page 1 of 1

Rear bearing noise

Posted: Sat Jun 11, 2016 3:36 am
by pandabearjohnson
When I got off the freeway last night after a 100 mile ride I could hear what sounds for all the world like the rear bearing grinding away. I had heard it before but tried to convince myself it was just the brake pads dragging. After yesterday there is little doubt in my mind. I intend to tackle it myself as I make my living as a mechanic (boats, not wheeled vehicles!) but thought I'd ask is anyone has a link to a step-by-step guide. Also, are there any special tools (bearing puller for example) that I would need. And finally, is there anything else I should do while I have it all in pieces? I'm going to change the FD oil and service the rear brakes, anything else?

Thanks

Re: Rear bearing noise

Posted: Sat Jun 11, 2016 7:38 pm
by Sunbeemer
If the rear bearing is bad, you should see lots of shiny metal flakes on the final drive's drain plug magnet. A smudge of grey "mud" is normal, but bits of shiny metal often indicates bearing failure.

Re: Rear bearing noise

Posted: Sat Jun 11, 2016 7:42 pm
by towerworker
Put the bike on the center stand and grip the wheel at the 12 and 6 positions as well as 9 and 3 and try wiggling the wheel back and forth. If you can feel it move just the very slightest amount then that's a bad sign. But all the noise you're describing sounds pretty classic. And as what Sunbeemer has said is very accurate.


This might help:

http://advwisdom.hogranch.com/Wisdom/Fi ... 20R&R.html

Re: Rear bearing noise

Posted: Tue Jun 14, 2016 5:08 pm
by peels
I wouldnt rule out worn pads and sticky caliper. Thats How I first noticed my problem. A grinding noise.

Re: Rear bearing noise

Posted: Wed Jun 15, 2016 10:12 am
by racurley
I had a failed crown ring bearing and oil seal on the FD which I replaced. I found a number of good threads on this process on the internet. There are good detailed descriptions of this but basically it was
- Drain FD oil and check what's on the plug. I had chunks of metal on it. Not good.
- Removed rear wheel
- Put a couple of wheel bolts back in for handles and remove the FD cover (leave swingarm on the bike.) and the big gear.
- be careful with the shims
- I left the smaller tapered bearing alone.
- Remove the bad ring bearing. Use pullers if they fit. I had to start mine with a chisel. Read about that somewhere. Be careful with the chisel method.
- Clean everything up really well on all parts to get rid of debris.
- to put the new bearing on, crown gear in freezer, bearing in oven (or use heat gun), bearing will drop right on the cold part.
- I didn't re-shim mine because I wasn't sure how and also because the BMW dealer wanted to rebuild the entire FD rather than just shim it for me. I've seen some discussions on calculating this using solder wire that look interesting. There are a number of ways to DIY but can be a little challenging.

If I find the helpful links I used, I'll post them.