Clicking sound in the driveshaft area

[Ken in Oklahoma]

I've been watching this thread intrigued by a "clicking" sound to a BMW driveline, trying to imagine what could go wrong that would manifest itself with a click.

Now I have heard driveline sounds before when pushing a bike along a concrete floor. Those sounds reminded me of the sound of meshing gears, perhaps in the transmission or perhaps in the final drive. The sounds that I heard I would not describe as clicking. Clicking to me suggests a high frequency content to the sound. The sounds that I heard pushing a bike along a concrete floor were dull, with little high frequency content to them.

Also, I seem to remember a thread from long ago where a particular regular driveline noise was thought to be a bad universal joint, not necessarily loose, but worn or stiff enough to generate a dull kind of noise.

So I guess the question I'm posing to Ken is if he could somehow refine the description of the sound. For example, is it rather dull in sound, or is it a sharper, quicker sound such as, well, a click?

Another question that comes to mind in an attempt to figure out Ken's bike's sound would be whether it happens regularly with each revolution of the wheel (thus pointing to the wheel itself and certain innards in the final drive) or does the sound occur more frequently, say about three times for each revolution of the rear wheel. That would point to something having to do with the driveline itself.

The fact is that I'm as stumped as others here, and perhaps an answer to my questions might elicit some new ideas.



Ken

[Duane Ausherman]

I should have asked how many times the click occurs per wheel revolution. That is very important in the diagnosis.

[rheritage]

Not sure if someone covered this already but I just went through that on a newly acquired 100RS, turns out PO did not tighten the driveshaft bolts to the transmission flange. By the time I removed the boot after isolating the sound, two of the four bolts had backed completely out and were rolling around in the drive shaft housing and the two remaining bolts were half way out, could have been a very nasty lockup plus internal damage.

The sound starting with a clicking sound, more noticeable when rolling the bike backwards.

Good Luck!!!