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Would a failing/failed thrust bearing cause the clutch to disengage under some but not all loads? Is there anything else that could cause this noise and behavior?

I will drain the gearbox and take a look at the plug this weekend, but would like to order the bearing now if that's the 98% culprit.

With the lack of slack in my clutch cable (BAD RIDER!) I wouldn't be surprised if I fried that creaing.

It is a quick removal, so fully diagnose it before spending money. Always.

Manfred wrote:Would a failing/failed thrust bearing cause the clutch to disengage under some but not all loads? Is there anything else that could cause this noise and behavior?

I will drain the gearbox and take a look at the plug this weekend, but would like to order the bearing now if that's the 98% culprit.

With the lack of slack in my clutch cable (BAD RIDER!) I wouldn't be surprised if I fried that creaing.

It could be any of a multitude of things - broken things inside the gearbox, universal joint connection, final drive etc. The drain plug and thrust bearing inspections are just the easy things to check first before you have to gird your loins (while maintaining good access to your wallet) and dive in to the really intimate parts of your bike. From your description the thrust bearing is a suspect worth interviewing but you would expect the symptoms to not be restricted to first gear.

It would help if you could put together a clear description of symptoms. Is the clutch actually slipping (revs climbing with little or no increase in speed) or is the bike seeming to jump into and out of gear? If you put the bike on the centre stand, prop up the back end and spin the rear wheel, what sort of noises do you hear, if any, and can you pinpoint the location?

Airbear - When this first came to my attention, I had just left the office, heading to the store at lunchtime. Took a left turn in first gear and it felt like the centerstand had not been fully retracted. I pulled over and checked things out - nothing showing. Got back on and when in 1st gear only that baby rattle noise and the bike felt like it was jumping in and out of gear.

I rode it 20 miles home and was very gentle on the throttle. Shifting to 2nd at 3,000 rpm and riding at up to 60 mph in 5th produced no symptoms. No slippage of the clutch at speed that I noticed, no problem motoring up the hill on our driveway (70 feet elevation change over 700 feet of road) in 2nd gear.

Sitting on the centerstand in the garage - baby rattle noise with the clutch engaged. There was NO wiggle room on the clutch cable - I had not checked it in a long time. sigh

I just want to say - this site is the BEST for getting solid advice about airheads. Ya'll are great and I thank you.

Hmm, ok. A rattle with engine idling and clutch lever out is common and no problem if it goes quiet when you pull in the clutch. If it's unusually loud and metallic it may be a problem. It's pretty hard to diagnose such things from the other side of the planet. The sensation of jumping in and out of gear may be more of an engine 'miss' problem, particularly if it is happening at 5000rpm.

So do check out the transmission drain plug and what you hear and feel when you rotate the rear wheel - engine off and transmission in neutral - and report back.

One thing I am sure about - no miss with the engine. She runs smooth without hiccups. Improved grounding and new coils & spark plug wires a few years ago helped out a bunch. The noise and jumpiness happens around 3,500 rpm. The only time she got above 4,000 was on the ride home Wed and no misbehavior nor noise noticed (ear plugs).

It's been busy for me of late. Had some time this evening to get started replacing the thrust/throw-out bearing. Clymer's manual. Have the cable disconnected, the pivot bolt out, the boot loosened up. How on earth does one remove the clutch lever? The bolt on back side of it has very little clearance before it bumps into the housing for the rear suspension pivot (forgot what that's called). I have not been able to pull it towards me (left side of bike). I am cursing the Germans right now.

Any suggestions?

I was able to remove the pivot arm - pushed it away from me and it dropped free. Have removed the cover that covers the thrust bearing but cannot figure out the bearing! It's in the housing where it belongs and I can feel it but no way to get a grip on it to pul it out.

Suggestions?

A strong neodymium magnet?