What's this rattle?

[Tv]

My bike has developed a serious rattle or clunk noise in the engine or gearbox.  When I start the bike it's really loud. After it warms up and is idling I can hear clunkety clunkety.  It's louder at the gearbox end and when I pull the clutch in there is a very slight change in the level of the noise. It's hard to explain in words and I dont know any BMW enthusiasts who can diagnose the problem in person. I did a service and oil change about 500 K's ago.  It's definitely gotten worse over the last few rides.
Where do I start the process of elimination?
Thanks
Tony

[Bob_Roller]

I would start, with draining the lubricant from the transmission, and checking it for excessive metal content .

[Semper Gumby]

+1 what the others have said.. but...

The worst rattle I ever heard from my R65 was the Reynolds Rideoff center stand bouncing off one of the muffler clamp bolts going through 3000 rpm.  Scared the sh%t outta me.

Is the RH rear axel bolt tight enough??  Check the rear wheel bearings.  The both should be perfectly smooth when rotated.  Are the dust seals OK.

Start at the final drive and work your way forward.

Pull each piece off and check for smoothness of rotation.

Look for leaks and funny chocolate colored fluids.

The final drive should turn smoothly by hand with no grinding.  Check the splines for excessive wear.

The drive shaft universal joint should turn freely in both axis with no "notchyness" or stiffness/tightness.

Same with the tranny.  select each gear and turn by hand listening for grinding.  Also check the input spline and make sure the male part on the tranny is not worn to nothing and that the female side in the clutch friction plate is the same put grease only on the male part when you re-asemble.  Do the throwout bearing service and check those pieces.

Look at the clutch assembly and make sure the bolts holding it together are still there and tight.  Grab the fly wheel and see that it is not loose side to side and for and aft.

Reassemble everything to the right torque and put in new fluids.

Its rather daunting but at least you wil know everything is alright.

Is the clunck when you shift and let the clutch out or all the time?

Re-assemble replaqceing anything that doesn't look new. (Rubber bits and seals)



Good luck.

[Tv]

G'day and thanks for the advice.  I found the front left indicator stalk has broken from the the front mounting plate and that along with the way the fairing is mounted was causing more than a few confusing sounds - squeaks etc.  I used a couple of cable ties to stop that which caused some other noises but I can fix that. It's so quiet now
I got the big screwdriver out and did the stethoscope thing while the engine was idling and I think I've got a knock/clack around the middle of the motor.  Could be in the crankshaft area. The rest of the system from front of engine to back of trans rattles and whirrs but sounds consistent.  It's the knock that worries me
How can I tell if the oil pressure is down?
Thanks and regards
Tv