/2 CLUTCH GRINDING / PINGING NOISE - ANY IDEAS?

[schrader7032]

With Vech doing the work, I would think that everything would have been covered or looked at. Funny that Ted Porter is booked 'till 2009!! Kidding, I know but still... I read his posts on the Airheads lists and he is a good resource.

Is the noise a constant sound (as in two surfaces in constant contact or rubbing) or a hitting sound (like something is hitting once per revolution)? Does the sound change any when the clutch lever is let out? With engine running, in neutral, do you feel anything if you were to try and move the lever at the back of the tranny by hand forward to take up the slack and engage the throwout bearing? Do you have a mechanics stethoscope to try and isolate the sound? You could even use a longish cardboard tube or even a long extension for a ratchet. Put the extension in various places and put the other end next to your ear.

Ted's suggestion is a good one to remove the lever at the back of the tranny and pull out the few pieces back there. Just remember how each one comes out. The throwout bearing for the /2 should be a small circular disk with ball bearings in it. I recently pulled the one on my /7 and it has cylinder bearings rather than balls. The cylinders, having some length to them, were a bad idea because the inner part of the cylinder and outer part of the cylinder have to turn at the same speed but they really can't because of the radius issues. So the cylinder actually skips along instead of purely rolls.

Pull yours out, inspect it, and clean everything, and reinsert. Put a little gear oil on the pieces when you reinsert. Don't try and pull the clutch rod out. There should be a small felt ring trapped near the end of the rod. If the rod moves back enough to expose the felt, it will be difficult to insert it from the rear. The easiest way to insert it is from the front with the tranny out.

This bearing is supposed to be lubed by splashing gear oil. Maybe the fluid level is low in the tranny and not splashing around thus causing the bearing to wear out.

A thought on the "hitting" sound if that's what's happening. I wonder if the screws that hold the clutch pack together have backed out and are possibily hitting the forward side of the tranny bell housing. Seems unlikely but a possibility.

Have you checked in with Vech to see what he has to say? He'll be more familiar with what he did and can make a better diagnosis.

Kurt in S.A.

[spwilmot]

Is the noise a constant sound (as in two surfaces in constant contact or rubbing) NO

or a hitting sound (like something is hitting once per revolution)? YES! A "TING" "TING" TYPE NOISE...

Maybe the fluid level is low in the tranny and not splashing around thus causing the bearing to wear out. GOOD THOUGHT, WILL CHECK

I wonder if the screws that hold the clutch pack together have backed out and are possibily hitting the forward side of the tranny bell housing. Seems unlikely but a possibility. THAT WAS MY FIRST THOUGHT. HOWEVER ARE THESE VIEWED/INSPECTED DURING A TRANNY R/R? AREN'T THESE THE SCREWS PUT IN WITH A MANUAL IMPACT DRIVER? IF THESE ARE THE CULPRIT, WILL HAVE TO WAIT FOR TED AS IT INVOLVES PULLING THE TRANNY AND IS OUT OF MY LEAGUE (OR MAYBE I AM WISE ENOUGH NOT TO F%$# WITH STUFF I HAVE NOT SEEN OR EXPECT TO SEE OFTEN)

TED SAID TO CHECK THE BEARING ASSEMBLY FIRST. I WILL LET YOU KNOW. JUST DON'T KNOW WHAT SIGNS OF WEAR I COULD OVERLOOK WHEN I HAVE IT OUT. HATE TO BUY NEW PARTS IF THIS IS NOT THE PROBLEM IN THE FIRST PLACE...

THANKS FOR YOUR INPUT.

[schrader7032]

I sure sounds like something from the clutch pack is hitting the front of the tranny. I suppose that it does it while the clutch is disengaged is because the clutch pack deforms a little bit due to the pressure when the lever is pulled in. Was there any service done on the clutch while the tranny was out? If the clutch disk is non-OEM or if the 6 countersunk screws that hold the clutch pack together were changed to be allen head bolts, then there might be a clearance issue. I put countersunk screws back in on my /2 but used blue loctite as an added step to keep the screws in place. I don't think there's anyway to see these bolts without pulling the transmission. I just did a spline lube on my /7 and didn't remove the transmission or even disconnect the transmission from the driveshaft. I did remove the swingarm pivots so the loosened tranny could slide back about an inch so I could clean and lube the splines. It's not difficult but does take some thinking and time to get done, even on the /2.

Check the throwout bearing...you should be able to handle that easily. If the ball bearings look clean and shiny, then I'd shove it all back together. I kind of doubt the bearing is the problem. I think there's a clearance issue between the clutch and the tranny.

Good luck...Kurt in S.A.

[Darryl.Richman]

It sounds like you've swapped transmissions. It may be that your new transmission is incompatible with your clutch.

If you have the /5 style clutch cover plate, which is sometimes considered an upgrade, it has strengthening ribs on it that stand proud over the /2 versions. When I first put my /2 together, the shop that rebuilt the motor had used one of these plates, and the ribs wouldn't pass the ribs cast into the inside of the bell housing on the transmission. I had to file away a small amount of the tranny ribs so that it would pass.

[VBMWMO]

The clutch on my R69S makes a slight pinging/grinding noise when "disengaged" (ie. clutch lever pulled in). Like it is hitting something as it goes around (clearance?) Other than this noise, bike just purrrs. Ted Porter (without seeing the bike, he's booked thru like 2009...) says to check the bearing cage assembly on the end of the clutch thrust rod first. This involves disassembling the clutch lever on the back of the tranny, pulling out the seal ring and thrust piece assemblies, then removing the ball cage bearing assembly with a long magnet, and inspect.

Before I get off my lazy ass and do this (instead of typing away here for 15+ minutes) has anyone else encountered this clutch noise on a /2? Weird. Bike came back from Vech (I delivered it to him personally, long story) at Benchmark. And it started making this noise 250 miles into the break in. He did have the tranny out to swap it with one with a rebuilt I supplied.

Ted also said to view into the timing indicator hole and pull the clutch lever. Said any forward movement VERY bad (crank play) However, I did this and did not see any whatsoever.

Also, Vech did a lot of work (top end inspection, new valves, coated cylinder walls, etc.) I am sure that crankshaft play would have been diagnosed and included if he suspected any sign of anything in the lower end. Unfortunately, getting it back to Vech is slightly inconvenient.

Now I know why out of probably 15 attendees to a "Vintage BMW" breakfast at Joe Groeger's shop, I was the only one on a vintage bmw (that "ran"). the other was someone with an R69S . I will not name him as his R69S restoration is well documented on the web and he took a helluva ribbing from onlookers when the carbs wouldn't do as asked. He didn't make it out of the parking lot when we saddled up to drive to the diner for breakfast.

Am I the only ever-youthful (i.e. naive) sucker to love these machines too much? Hey, I havn't run mine since that weekend (2 months ago) but it looks great sitting in the middle of my office if only to view it.

Scott Wilmot, San Francisco Bay Area c 925-285-5555