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Anyone know what is an acceptable amount of play in the rear floating rotor on my '03 LT? I have a noticed a metal-to-metal clanging that has been getting progresively worse (hitting potholes, expansion joints, rough road, etc). I traced it to the floating rotor. I checked the torque on the two sunk screws that hold it fast and its OK. But, a little un-nerving to hear.

Thanks,
Bob L
 

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There should be about 0.5 MM (0.020") float of the rotor, controlled by the wave springs between the riveted bushings holding it to the carrier. If the wave springs have broken and come out, then the rotor will rattle.

The two screws holding the rotor carrier to the axle hub have no bearing on the rotor float or looseness, as they are only there to retain the carrier when the wheel is removed. The clamping pressure between the wheel and hub when the wheel lug nuts are tightened is what resists the braking force.
 

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I too have suffered with the 'cow bell' for some time. The dealer said that they replaced the rotor with a new unit, but only bent the retainer to keep some force on the pads against the rotor to stop the clang. It did stop the 'bell' but heated the rotor something awful from the friction and I could not push the bike backwards because of the pressure on the rotor - which is how I found out about the "fix" the dealer did. I was not impressed. The reason for my reply is to find out if anyone has ever seen any kind of clips on the rear rotor which would stop the noise. Every LT I have ever seen is missing these items - new and old - and I check every time I meet a new rider and think about it.
 

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Can you explain what clips you are referring to?
 

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The one piece retainer that holds the pads (until you put
the pins into the slots). Just take it and bend it more than the slight arc it is now and force it flat at installation. That's what the dealer did. I took it out and bent it back like it was. It did stop the 'clang' but at too high a cost to me.
 

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Sorry answered the wrong question. The wave washers mentioned in the answer to the first post. I have never seen them on a REAR rotor. They would be a big help in stopping the clang if they were there. Any idea where some slip on wave clip could be located that would fit the rear brads?
 

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lnowell said:
Sorry answered the wrong question. The wave washers mentioned in the answer to the first post. I have never seen them on a REAR rotor. They would be a big help in stopping the clang if they were there. Any idea where some slip on wave clip could be located that would fit the rear brads?
They are on the rotors from the factory, at least on the '99-'01 models. Not sure what changed when the brake systems changed for '02. They are thin wave washers between the rotor and carrier/retaining bushings.

I had rear brake squealing problems on the LTs, but never had a rotor rattling issue.

Did the rotor retaining methods change in '02?
 

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mine is noisy too, but only at low speeds trundling through town. at speeds of over 20 mph it goes away. i just assumed it was a feature of the floating rotor and ignore it. one of the bike's little peculiarities.

i definitely prefer the low-speed noise to binding in the rotor.
 

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David,

I have an 01 and do not have the washers - wish I did. My build date is September 00 so it must have changed before that. You have to hear the 'clang' to really appreciate how noisy it can be. It really does sound like you have a cow bell hanging under the bike. Mine even rattles at startup - until I press the rear brake to shut it up.
 

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Sounds like they over-bent the pad retaining clip. A very little pressure is probably OK, but too much would be bad.

I'm not sure if the wave washers come on the newer rotors or not, but the rotors do loosen up over time. Cow bell about covers it. Overall braking function doesn't seem to be affected at least.
 

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I had an "UNBELIEVABLE" clunking, rubbing, metal to metal grinding noise when the bike was leaned into a curve. The owner of the dealer suggested I replace the rear tire. I had lots of tread left on my metzlers. I even had the rear rotor replaced under warranty... no fix. As a last resort, I replaced the tires.

It fixed it. The only thing I can figure is that when the tires wore, they cupped. The cupping set off some sort of harmonic resonance in the rotor.

Been good ever since. Go figure.
 

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I took the rotor off and shot some red, high-temp RTV, between the rotor and the carrier and it helped for almost a year, then I did it again.

George
 

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2003-- you will find that the studs the rotor floats on has a machined groove around each one, a c-clip goes in that groove and the c-clip wire takes up the gap so not to rattle, this clip will not hold the tension after many heat and cool down periods, short of replacing the rotor I found no other fix...matthew
 
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