Clutch cable stretching? Need part number....

[VaSteve]

I went for a ride today and as I got closer to home, I was having increasing difficulty keeping the bike running.  It'd stall out in first gear at lights.  The bike was also getting harder and harder to shift.  

I nursed it back home and it appears that the clutch handle is a lot easier to squeeze than it used to be...even the last time I rode the bike.

When I inspected it off the bike, it seems that when squeezed, it's pulling the transmission mount, but not by much.    In fact, when the bike is running and I squeeze the handle, I can hear a squeaking....I'm assuming the clutch almost disengaging.  

I figure the cable must have stretched a bit out of spec and I was going to replace.  I looked at A&S fische and I couldnt't find the cable listed.   Anyone know the part number or where to buy?  How much is it?

Other feedback welcome of course.

[Barry]

I think I would inspect for other things as well as the cable stretching. The cable wouldn't stretch that fast unless it was already down to a few strands of wire. Other possibilities might include the clutch operating arm pivot pin is falling out (and that would need catching quick before one of the posts on the back of the gearbox breaks off) or the clutch actuating push rod is severely worn.

[VaSteve]

Is the push rod a wear item?  I messed with it a little now that it's cool.  The travel when pushing on the clutch is little at the rear of the transmission.   I turned the adjuster nut in a little and it the handle got stiffer, but it's not the "right" solution.  A couple passes up an down the street showed that it's very jerky.  *Something* is out of adjustment/spec...I'm terrible at figuring out what.

[donbmw]

Check you through out bearing. What you are describing  is alot like the through out bearing is going. I had this happen to my R90/6 and is was like you are talking about.

Don

[Bob_Roller]

Have you checked the cable end fitting at the handlebar ?

I had one fray at the swagged fitting at the clutch lever, it prevented the cable from going back into the outer sheath/conduit .

[VaSteve]

Check you through out bearing. What you are describing  is alot like the through out bearing is going. I had this happen to my R90/6 and is was like you are talking about.

Don

Which part is the throw out bearing?  (Please tell me it's outside the transmission.   )

http://www.ascycles.com/Illustrated_catalog2/MicroList.aspx?id=51626&catID=21&catname=Clutch&bindName=CLUTCH_CONTROL&bindCat=21_0086

Bob....no visible fraying.   :-/  

[Bob_Roller]

Item number 3 .

How about the adjustment bolt at the arm on the transmission .

I had the jamnut come loose and the bolt backed out .

[donbmw]

What Bob said on Item #3.  Did not think about the jam nut coming loose and letting the bolt back out.

[VaSteve]

Item number 3 .

How about the adjustment bolt at the arm on the transmission .

I had the jamnut come loose and the bolt backed out .

Throwout bearing looks easy to inspect/replace.  Will check on it tomorrow.

I initially thought the adjuster nut as well, but when I decided to mess with that, it was stuck pretty good....tightening it up didn't help.

Will report back...thanks.

[Rob Valdez 79 R65]

If it is the bearing, keep in mind that A&S does not show the fiche for the '78-'80 models, only the '81-'84.

THIS is the correct fiche.  Part #4.
Still easy to access.  But you will need a magnet-on-a-stick.

http://www.realoem.com/bmw/showparts.do?model=0363&mospid=51897&btnr=21_0069&hg=21&fg=51

[Rob Valdez 79 R65]

And check your handlebar control end of the cable.  Make sure it is greased as stated above.  The bottom end needs love, too.



I put some 90 wt oil on the throwout bearing when assembling it.

The end of the pushrod where it contacts the clutch plate can deform.  It requires a small dab of moly grease when you have the transmission removed for other reasons.

Here is a good article comparing the throwout assy's from various years:
http://www.largiader.com/articles/throwout/

Here is a link to an image of a worn push rod compared to a good one:
http://w6rec.com/duane/bmw/clutch/PushRodTit.jpg

From Duane's page on the matter:
http://w6rec.com/duane/bmw/clutch/index.htm

[VaSteve]

If it is the bearing, keep in mind that A&S does not show the fiche for the '78-'80 models, only the '81-'84.

THIS is the correct fiche.  Part #4.
Still easy to access.  But you will need a magnet-on-a-stick.

Good to know on the link, that burned me on something else.  I'm a pretty crappy mechanic....I have LOTS of magnet-on-a-sticks.  

The whole bike was apart for cleaning, repainting...except this part.   I'm wondering if it got ruined while I was doing some of the cleaning on the transmission?  Hmmm, we'll see.

[Rob Valdez 79 R65]

I had that small bearing get trashed on me when my bike was less than 5 years old.  Since then I've watched it carefully, carried a spare, and never needed it.

But I did forget to refill my gearbox with oil one time.  Now I have a new used box in it's place and one VERY trashed one sitting in the back of the garage.  I'm not even sure if the case is worth anything at this point.

That is another motorcycling mistake I will probably never repeat.

[VaSteve]

OK, so it was the throw out bearing.  I took the clutch lever off and put my magnet in and got nothing but needle bearings and metal dust out.  There was no cage for them at all.

I was trying to get the washer #3 out but it appears to be stuck on the clutch rod.  Then Bentley manual and the links provided say it's not possible to remove the clutch rod with the transmission on, but I was able to grab the rod with a needlenose and pull it out as far as the swingarm.  You can see in the photos that on the backside (inside) there is a lip.  On the outside, there is not, but I couldn't pull off the washer.  If I *could* pull off the washer, I can't tell if the rod is actually trashed or not.  I'm also trying to figure out if I loosen the swingarm, can I pull the whole mess and replace all the parts.  Thoughts?  Possible?

I assume during normal operation, the rod slides in and out of that washer?   Which leads me to....how exactly does this set up work?    The arm presses the piston (#5) which I assume presses the rod.  But if the piston doesn't actually move, then does it just press on the bearing/washer surface?

From one of the sites:

The clutch throwout bearing allows the clutch actuating arm (on the rear of the transmission) to push against the clutch which is spinning at engine speed. The arm pushes against the bearing, which pushes the pushrod through a hole in the input shaft against the clutch diaphragm spring. The spring and the pushrod spin at engine speed, and the bearing isolates that movement from the actuating arm which obviously doesn't spin.

See the "lip"?


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[VaSteve]

Hmmm.... my problems seem very similar to this thread:  http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1203980214/60

Page 5 and 7 have the gory photos.