This sounds like $$$$$

[twins4life]

The idle "screech" was suggested to be a slipping alternator belt. New belt and the proper tension, no improvement.

Recap of symptoms: Idle "screech" worse as RPM increases to 3000

Comes and goes, sometimes no problem at all. Other times sounds like a seizing bearing.

Here is the kicker: Squeeze the clutch lever and the "screech" goes away completely. Release the clutch and the screech is back.

???????????

Bike runs and shifts just fine.


Ideas?

Clutch release bearing is my first guess.

Any suggestions appreciated.

[beeryboats]

Yup, sounds like throw-out bearing (clutch) to me too. How tough is it to pull the trans on a beemer anyway? That's one thing about some of the older Hondas, the wet clutch never wore out.
Jay

[easy]

I agree, sounds like a bad throw-out bearing.

Easy

[twins4life]

Yup, sounds like throw-out bearing (clutch) to me too. How tough is it to pull the trans on a beemer anyway? That's one thing about some of the older Hondas, the wet clutch never wore out.
Jay

I had the tranny out of my 97 once to grease the splines. Not bad just a lot of work...

Correct me if I am wrong, to get at the clutch slave cylinder/release bearings you just remove the swing arm

[PGlaves]

It seems to me that a throwout bearing has no pressure on it, and no reason to screetch unless the clutch is pulled. So, unless the clutch adjustment is off so there is no free play, a bad throwout bearing should only screetch when the clutch is pulled - not vice versa.

A noise that goes away when the clutch is pulled but is there when it isn't pulled sounds to me like it is related to the transmission input shaft. When the clutch is pulled what stops spinning is the transmission input shaft. I suspect a bearing is starting to fail.

[AntonLargiader]

I would drain the tranny oil without delay. You'll know good vs. bad when you see it.

[twins4life]

Yep, after several PM's with PGlaves, a drain and magnet inspection is the next step.

Since I forgot to specify it is the 2002 RT 6 speed. Assuming the tranny is the culprit (most likely) would I be better off having it rebuilt or are the later model 6 speeds better than a rebuild?

[AntonLargiader]

The later ones are slightly improved, but I don't think it's something worth buying a different transmission for unless you know it's a good tranny and it's cheap.

If you're an RA member, you'll see a quite thorough description of the six-speed transmission in the January magazine.

[PETDOC]

Comes and goes, sometimes no problem at all. Other times sounds like a seizing bearing.

Here is the kicker: Squeeze the clutch lever and the "screech" goes away completely. Release the clutch and the screech is back.

???????????

Bike runs and shifts just fine.


Ideas?

Clutch release bearing is my first guess.

My '04 GS had nearly exact same symptoms. Intermittent screeching when clutch out, but stopped when pulled in; bike ran fine. It was the bearing in clutch slave cylinder. On the GS you can change the slave cylinder without pulling the transmission, not sure about the RT.

[twins4life]

My '04 GS had nearly exact same symptoms. Intermittent screeching when clutch out, but stopped when pulled in; bike ran fine. It was the bearing in clutch slave cylinder. On the GS you can change the slave cylinder without pulling the transmission, not sure about the RT.

Let me double check the verbs here:
Clutch lever RELEASED = intermittant screeching
Clutch lever SQUEEZED (as in shifting gears) = NO screeching?

Just want to double check.

Thanks

[PETDOC]

Let me double check the verbs here:
Clutch lever RELEASED = intermittant screeching
Clutch lever SQUEEZED (as in shifting gears) = NO screeching?

Just want to double check.

Thanks

Exactly. I first noticed the intermittent screeching when I got home from a short ride. I had stopped in front of the garage, the bike was running, but in neutral with the clutch lever out. The screeching was intermittent, very scarey and did not seem to be associated with rpms. After thinking "Oh s**t" I tried to localize it and found that every time I pulled the clutch lever in it abruptly stopped and when I let the clutch lever out it would frequently, but not invariably start screeching again. I took bike back out for a ride and it worked fine, but the screeching was intermittently ever present. I believe it was there even when I was moving, but much harder to hear due to helmet and wind/engine noise.
I initially thought it may be alternator, but with chat group advice narrowed it down to slave cylinder or clutch. I removed transmission and changed perfectly good clutch, lubed pristine splines (31,000 miles) and then confirmed it was the slave cylinder. At that point it was an easy change, but since then I have read that on the GS you can do it without even removing rear end, just remove rear wheel and shock. Probably helps to have a slender hand.
When I ordered new slave cylinder from Hammersley the parts guy said that they have a relatively high failure rate on hydraulic clutches. As I recall parts were about $110. Don't forget to get the 4 small crush washers that go between the 2 hydraulic lines which bolt to slave cylinder.
When I took mine off there was a lot of black grease in the cavity of transmission where clutch push rod sits, which took a while to clean out- new slave cylinder has light tan grease on top of bearing so I assumed that was source.
I have read that the real danger is if throw out bearing breaks its seal it will allow clutch fluid to travel up push rod and contaminate clutch necessitating clutch plate replacement. When I took my slave cylinder off it looked ok, but I took a small screwdriver and gently pushed on throw out bearing of old and new slave cylinders and it was obvious the old throw out bearing was toast. Actually shortly after I started to manipulate old throw out bearing small ball bearings came cascading out.
After putting everything back together I was getting ready to bleed the clutch by first removing clutch fluid from handelbar reservoir and noticed it was very dark (I change it yearly). At the time I didn't think about the color, but have subsequently read it can be associated with a bad throw out bearing. I guess if a bad bearing can let clutch fluid out it can allow the grease to be aspirated back into system??

[twins4life]

Very interesting, your description describes my problem 100%.

At the last fluid change, I too noticed the clutch fluid was black and "pasty" looking. Perhaps the fluid fails from grease working back in or heat from a bad throw out bearing.

I guess at this point the checklist will be:
1. Tranny fluid change and magnet inspection
2. Remove the clutch slave cylinder, remove the push rod, reinstall the clutch and test run the engine (depending on if that seems like a good idea)

Thank you for sharing your experience and I will post results after I get them.

[twins4life]

UPDATE:

Tried to check the tranny magnet but dont have the correct allen head bit. Mine go from 12MM to 17MM. Anyone know the size so I can buy just one? My guess is 14MM.
I felt ambitious and decided to inspect the salve cylinder/release bearing. YUC. The tranny side was ooozing a brown, gritty sludge. The bearing itself felt a little rough but spun easily. The tranny oil is the correct color via an sample from the fill hole.

The brown sludge is the same color as the clutch fluid the first time I changed it (bike was used and I dont think the fluid was ever changed).

Conclusion:
Tranny condition: unknown pending purchase of new allen head bit.
Slave cylinder: Leaking
Release bearing: Questionable.

I started the bike without the slave cylinder installed and no noise.

I'm not comfortable with the torqueing on the plastic hydraulic line at the attachment to the slave cylinder. There is just not much wiggle room. I may replace that line as well.

So far I have removed the exhaust, side tupperware, shock. The is a frame cross bolt directly behind the slave cylinder, any idea how difficult it is to get out?

Thanks

Now...

[twins4life]

Another question:

The dealer suggested some BMW mineral oil for the clutch circuit, which is what I put in when I changed the fluid 6 months ago. The top of the reservoir on the master cylinder says DOT4 brake fluid.

What am I supposed to use?

[deilenberger]

Another question:

The dealer suggested some BMW mineral oil for the clutch circuit, which is what I put in when I changed the fluid 6 months ago. The top of the reservoir on the master cylinder says DOT4 brake fluid?

What am I supposed to use?

DOT-4 AFAIK - and according to my service manuals.

The dealer may have done you a disservice (although I understand you said the fluid was gunky last time it was changed..) The seal material made for DOT-4 fluid isn't necessarily compatible with mineral fluid. That may have caused your seal failure. The rough feeling bearing and the brown gritty sludge make me believe a new cylinder and a complete flush of the system with DOT4 should make the noise go away..