underpowered r65 - clutch? timing?

[kls1]

Hi all,
so recently I was feeling my bmw struggle just a bit. Then it started struggling a lot. Now it pretty much struggles going around town.

-The facts:
- I need to adjust the clutch at the bars all the way in so that I can get some engagement and power. so this means instead of the usual 200mm of cable showing...i'm somewhere in the range of 214mm.
- I can still get around town, going 30-50mph...but it feels significantly underpowered, and when I go up hills, I need to really gas it and reach high rpms (6000)
- the clutch cable is about a year old

My guesses:
Timing and a worn clutch plate?

[Bob_Roller]

There are two adjustments for the clutch cable, one at the handle bar, and one at the lever or arm at the back of the transmission .

Have you checked the adjustment bolt at the transmission, to see if it has loosened up ?

[kls1]

Yeah, basically my strategy when adjusting was to first use the handlebar adjustment to get in the ballpark of 200mm. from there i do the lever arm adjustment to get rid of the slack to 2mm of opening the clutch...

then i would go back and forth between the two until i was happy.

BUT now, i basically had to eat up as much slack as possible and screw the handlebar all the way in...and i am definitely still feeling underpowered. (and i fixed the lever at the back to be correct).

[Bob_Roller]

Could you explain the under powered aspect, does the engine rev up, and the bike is reluctant to move, or is it more like you open the throttle, and the engine doesn't respond like it should ?

[montmil]

Begin your clutch cable adjustments at the clutch end. Get that specification spot on, then move to the handlebar tweaks. You could possibly be riding with a slipping clutch.   Monte

[nhmaf]

Yes, "underpowered" implies that the engine is stumbling or unable to accelerate, though if someone isn't familiar with a manual transmission clutch and what it does when slipping, they may appear to be the same thing.

If you are running along on flat road can you hit 65 MPH (do this on a road where it is legal to do this).   If you can, but going up hills your speed drops while your engine RPMs stay the same or go higher, then the clutch is indeed very badly slipping and either the cable is waaaay out of wack or you've got a failed clutch disk and/or diaphragm spring inthe clutch assembly.  6000 RPM in top gear should have you traveling at 80 MPH or more - if you are in 5th gear at that point and you aren't going wickedly fast with 6000 RPM on the tacho, there is serious slipping occuring and you've gotta fix it soon or will ruin your clutch plates if you have not already.

[kls1]

So I did ride around on the freeway for a bit thinking I had fixed the problem...but it never did feel right. Basically when I am going around 65mph, I'm at 6000rpm in the highest gear. It has a hard time accelerating overall...feeling weak at stops and also weak when in high rpms or going up hills. any suggestion on how to diagnose what exactly is the issue?

seems like people are saying:
worn clutch disk
diaphram spring
cable maladjusted (pretty sure I have tried my hardest to solve this -- giving the clutch as much slack as possible at the handlebars and then taking up the looseness at the clutch lever at the transmission)

[nhmaf]

You do want to get the 201mm length of the cable from the back of the engine "boss" that retains the lower end of the cable out to the nearest/inside edge of the 'barrel' or ferrule at the end of the cable that goes into the clutch arm at the back of the transmission pretty much spot on using the adjustment at the handlebar clutch lever end.  Once that measurement is correct and the cable is indeed conencted at both ends, one uses the screw and locknut down at the actuating arm on the back of the transmission to dial in the ~2mm of free play up at the handlebar lever.   you may have to first back out the adjustment screw and locknut some down at the back of the transmission first to ensure that you get the 201mm distance correct first.

IT might be possible that you have a failed/damaged throwout bearing and/or piston that sits inside the back of the transmission under that little rubber boot - but if so I'd expect that you would:
1) be hearing some nasty whining/grinding sounds and/or
2) be having trouble shifting gears.

since you haven't mentioned those, perhaps that isn't the problem.

HAve you noticed any oil leaks on the "shelf" (part of the engine's sump extends back and under the transmission - presence of motor oil there could indicate that you've got either a rear main seal leak or oil pump cover seal leak - either of which might contaminate your clutch disk(s) with oil and cause slipping even if everything else is properly adjusted.

[Justin B.]

At 6k rpm you should be traveling significantly faster then 65 mph so it sounds to me like your clutch is slipping.  Can you smell anything "strange"?

[kls1]

A few weeks ago, at 6k, I would be doing 80mph/85. So the drastic change definitely made me aware of a problem.

In terms of oils, it is a mess down there...but it's always been a mess. I've had this bike for about 4k miles, with around 46k on there now.

There's actually no trouble changing gears (pops in/out no problem). It sounds like people think I have a burnt up clutch? How easy is it to replace one of those? I'll do some more indepth investigating online tonight...

[Ed Miller]

http://www.suraklyn.com/r65_wiki/wikka.php?wakka=ReplaceClutch

[kls1]

Oh awesome! I definitely appreciate everyone's help. I have friday off so I might try to start some more diagnosis (with pictures to come) when I can start taking apart my bike.

Thanks!

But aside from being underpowered...what's the dangers of continuing to ride the bike? I assume I am wearing down the friction plate/disk more?

[Justin B.]

I would hazard to say that if your clutch is properly adjusted and it is still slipping it pretty much doesn't make any difference.  :-/  If it is slipping due to oil contamination it's possible you can fix the source of the oil problem and "de-oil" the clutch disc with lacquer thinner or brake cleaner.  To continue riding with a slipping clutch, though, will only cause additional wear and possible damage to pressure plate and flywheel...

[kls1]

So I went to move out the clutch assembly, when I realized I didn't have the compressing bolts that a lot of people recommend using.

BMW sells a kit which costs like 65 bucks I think....seems kinda like overkill for three bolts and the centering tool. Would anyone happen to know what I could pick up at the hardware store to get the job done? I assume I could just find a bolt similar to what BMW is using...and use that. THanks!

[montmil]

You'll likely have to force yourself to read this all the way to the end, but there are some important points that relate to your specific problems.

Read first, then, if necessary, tear down.

http://bmwmotorcycletech.info/clutch.htm

Monte