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Author Topic: Unsteady rear wheel unbalance.  (Read 1364 times)

EGRG

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Unsteady rear wheel unbalance.
« on: November 06, 2011, 09:00:55 PM »
Ive had the 1982 R65 LS for about a 3 months  and had a strange condition that I wanted to relate.
It would vibrate on occasions at different speeds. A heavy vibration not engine related that i suspected to be at the rear wheel. A little at first then it would disappear. Then it returned at 55 mph then at 50 Mph. I had checked tire pressure and was fine. The rear tire is a 4.00x18 Michelin Macadam with a tube.
I took wheel and tire off the bike and found it to extremely unbalanced just by holding it in my hands on its axle.  
After we took the tire off the wheel we found the inner tube to be destroyed and bunched up on one side but the air pressure was maintained by the macadam tubeless bead sealing with the tube type wheel. we believe that at first the tube was distributed around the tire but eventually bunched up on one side.
The moral is that even if things look correct it is better to check even the tires and tubes on new to you bikes.

Offline nhmaf

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Re: Unsteady rear wheel unbalance.
« Reply #1 on: November 06, 2011, 09:10:18 PM »
I'm very surprised that the air didn't leak out around the valve stem if the tub was shredded - the valve stem is simply part of the tube carcass and doesn't form an air-tight seal like the tubeless valve stems would
Airhead #12178 ? BMWMOA #123173 ?BMWRA #33525 ?GSBMWR #563 ?1982 BMW R65LS ?1978 BMW R100/7 1998 Kawasaki Concours

EGRG

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Re: Unsteady rear wheel unbalance.
« Reply #2 on: November 06, 2011, 09:43:13 PM »
Exactly my thoughts, but when we removed the valve stem it was at the center of an area of tube that shredded from the rest and was stuck on to the rim. I guess that it provided a good enough seal.

Offline montmil

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Re: Unsteady rear wheel unbalance.
« Reply #3 on: November 07, 2011, 07:42:10 AM »
This may set off the thread in another direction, but I've run my R65s tubeless for several years without issue. I know, I know...

Monte
Monte Miller
Denton, TEXAS
1978 BMW R100S
1981 BMW R65
1983 BMW R65
1995 Triumph Trophy
1986 VW Cabriolet

tvrla

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Re: Unsteady rear wheel unbalance.
« Reply #4 on: November 07, 2011, 10:51:09 AM »
Haven't looked at my rear yet but my new-to-me a year ago LS has been running tubeless in the front with no issues. Came that way.

Well done, getting that figured out! I wonder if they used the wrong sized tube - never heard of one bunching up like that.

Offline montmil

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Re: Unsteady rear wheel unbalance.
« Reply #5 on: November 07, 2011, 01:44:11 PM »
Quote
... I wonder if they used the wrong sized tube - never heard of one bunching up like that.

I'd make a smallish wager that the tube "they" stuffed into the tire may have been done by an unscrupulous shop lacking the correct size bladder. Another good reason to do your own maintenance when ever possible.

Good catch by removing the tire for a look-see. [smiley=thumbup.gif] Could've been nasty.

Monte
Monte Miller
Denton, TEXAS
1978 BMW R100S
1981 BMW R65
1983 BMW R65
1995 Triumph Trophy
1986 VW Cabriolet