The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: ddebonis on February 14, 2013, 10:52:21 PM
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I noticed my rear wheel wobbles a little. I made a video to show it. Pardon the shakiness, but you can sorta see and hear the wobble. Maybe the rear bearing needs to be replaced, maybe some bolts need to be tightened... What do you guys think? Anyone experience this before? How serious is this?
Watch my video: http://youtu.be/zHmLoHvN6go
UPDATE: this video is much better for seeing my issue: http://www.youtube.com/watch?v=aTJXaorKyHo
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Sorry, I couldn't figure out anything definitive from the video. If the wheel wobbles on the axle, it's gotta be bearing slop. Proper shimming would be required.
The question is how much play is there? How far does the rim deflect side to side?
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Outer rim has about 1/16 inch of wobble.
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Is it just me or did I not see the wheel turn ?
If you mean it wobbles with free play when you grasp the wheel and shake it then it's a bearing issue.
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Yes, it wobbles side to side. I tightened the axel bolt and problem solved.
However, now I am concerned with how the wheel rotates. I think the rear wheel always felt a little tight in terms of freely rotating, but when I tightened the axel bolt to ~25lbs of torque, it became much harder to turn.
New video of me spinning rear wheel. http://www.youtube.com/watch?v=lbvgVEWERxY
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If the wheel doesn't turn freely the axle is too tight, you may have bad wheel bearings, if you think the bearings are okay you may have the wrong spacers. There should be 2 spacers that slip into the oilseals either side of the wheel before the axle goes through.
There should be a gap of about 1mm between the wheel and the rear drive housing. If the wheel is binding here when the axle is torqued up you may need to swap the spacers over, pull them out and check the length.
I just looked at the first video and can see the wheel moving on the axle, it looks like a wheel bearing problem to me as axle nut torque shouldn't affect wheel bearing play.
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Now I know what I'm looking for I can see the movement in the first video. The axle nut was not torqued up at all when the video was shot - right ?
The correct torque for the axle nut is something like 30-35 ft lb however it 's not that critical and I'm happy if the bearing pre-load is not too high at 20 - 25 ft lbs. You need to feel the point where the bearing starts to load up by gradually tightening the axle nut while shaking the wheel. If it tightens up much below 20 ft lbs then either there is some part missing or the bearing pre-load is too tight.
What you shouldn't do is ride the bike any distance with too much pre-load on the bearing as it will eventually overheat and may spin the bearing in it's seat.
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Rear wheel bearings and oil seals often can be sourced at a local bearing shop for less bucks than a dealer. No harm in checking both sources. I would encourage you to pull the bearings for inspection, confirmation of any brinelling or pitting and replacement.
Pay attention to the "top hat" spacers as you remove them. Look for damage on these pieces. too.
Grasping the rear wheel at top and bottom, attempting to rock it side-to-side, there should be zero slop.
Have you previously removed the rear wheel top hats? Replaced them in the same position as removed? How many miles on the odo? I'm betting the bearings need freshening.
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The rear wheel will be harder to turn than the front, due to the fact you are moving the final drive parts, the drive shaft and some parts in the transmission, even if it is in neutral .
You best bet, is to remove the seals and bearings and see what you have .
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Hello !
When was the last time you put fresh grease in the wheel bearings.... ?
This will change the poor life those bearings suffer.... And if the old grease is 20 years old, it will look like cured concrete...
Take a close look at the small tubes onto which the seals runs on. They can broke and/or become somewhat distorted if the wheel axe is not torqued properly. On my bike, 3 of them where ruined (broken ) ad the fourth one was well worn...
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Here's a good article about the wheel bearings:
http://www.webring.org/l/rd?ring=bmwbikering;id=136;url=http%3A%2F%2Fw6rec%2Ecom%2Fduane%2Fbmw%2F
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I had front and rear wheel bearings and oil seals replaced after 40K. PLENTY of new grease. Along with having wheels trued major improvement in ride quality. Like rolling on a new bike...
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If the bearings are properly set up with the correct preload, they'll last forever - and if kept greased. These are the tapered roller bearings like in cars and trucks - they're waaaaaay understressed.
It's very common for the bearings to have the wrong preload from the factory, and I'll bet that's the case here. A thicker wedding band (one of the internal spacer rings) is needed.
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Thanks for all the help! I'll attempt to take this apart and inspect the bearings this weekend. I have since noticed a nasty grinding sounds. Praying that it's just a matter of replacing the bearings. :-[
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You state that you have tightened up the axle/bearings and are now hearing a "grinding" noise. Your rear wheel bearings are talking to you so listen to 'em!
Most likely, your wheel bearings have become brinelled. They won't heal themselves so must be replaced. The photo shows what bearing races can look like when they have been run loose or over-tight. http://en.wikipedia.org/wiki/Brinelling
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi196.photobucket.com%2Falbums%2Faa1%2Fmontmil%2FBMW%2520R65%2FOuterRace.jpg&hash=d0289c1608eafed1c9acc15078f7e50e56bd8e81)
If you have not replaced Airhead rear wheel bearings, let us know. It's not overly difficult but a few tips can speed n' smooth the process.
BTW, those nasty races you see came out of the headstock on my '83 R65. PO had not kept the steering bearings correctly snugged up. First day I had the bike, I could feel through the handlebars the slop and the "notchy" movement. Since your rear wheel bearings get a lot more punishment than the head stock, the grinding noise is to be expected. Same size bearings as in the rear wheel.
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Monte, are you saying the rear wheel bearings are the same part as the steering head bearings? I knew the swing arm bearings were but I didn't know about the steering head bearings. I have that clever Cycleworks tool and have used it to remove wheel and swing arm bearings. I would never have thought of a tool like that.
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Monte, are you saying the rear wheel bearings are the same part as the steering head bearings? I knew the swing arm bearings were but I didn't know about the steering head bearings. I have that clever Cycleworks tool and have used it to remove wheel and swing arm bearings. I would never have thought of a tool like that.
You're right, Ed. I had written down the wrong "forking" bearing size. ::)
Rear axle and swing arm both utilize tapered roller bearings 40x17x14
Steering stem tapered bearings are 28x52x16
I, too, have the Cycleworks stem bearing R&R tool. Nifty bit of kit, as Barry n' Lou would say. I had a bit of trouble with the "sharp-edged" machined washer and after completing the job, contacted Dan to buy a new one. No dice... Dan mailed a new one to me at no charge. The latest catalog view indicates it's now manufactured from brass or (?) as mine is steel.
http://www.cycleworks.net/index.php?main_page=product_info&cPath=29_33_50&products_id=64
Anyone shopping for Airhead specific tools should look through Dan's offerings. He has added many new products since acquiring the company from the Airhead tool guru, Ed Korn.
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I keep this on file which has the bearing Ref' numbers
(http://)
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The LS model bikes have a different bearing for the front wheel it's sealed .
It's BMW part # 36 31 242 854, 40x17x12 .
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UPDATE: I couldn't remove rear wheel so I took it to the shop. This is what they said:
"drained rear drive oil-no appreciable amount of metal on
magnetic drain plug, but significantly overfilled. tightened
axle and confirmed that wheel does become difficult to
rotate when torqued, attempted to remove axle, found
that wheel bearing inner race was siezed to the axle,
was able to remove it by removing the mufflers and
forcing it off of the axle. found that the inner wheel
spacer adjusting shim was missing and wheel bearing's
cage is broken. needs bearings, seals spacers and
shimming. also needs rear tire-tread depth is 0."
I can't believe the inner shim was missing! Happy to be alive.
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Right you are! That bald tire could have become a serious problem. ;)
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UPDATE: I couldn't remove rear wheel so I took it to the shop.
Pfft.. I'm surprised you found a shop to take it to. Sounds like they knew what they were doing, too!
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You probably needed to adjust the rear brake shoes, in with the nut on the threaded rod that goes to the arm on the right side of the final drive, so they wouldn't contact the brake drum inside the wheel .