Clutch Setting

[xeffer]

I asked this question in an old thread (http://suraklyn.com/yabb/YaBB.pl?num=1171572634) but did not recieve a response, so I'm hoping that starting a new topic might answer my question (sorry if this offends anyone)... Here is the question, exactly as I've asked it in the above thread.

I came accross this old thread, and would like to ask something... the 201mm setting at the back of the clutch cable... I understand that this only applies to '81+ bikes. What would the setting/procedure be for bikes made before 1981? does anyone know? I'm still waiting for my workshop manual.

I do have an additional question to the above one - The 2 nuts on the back of the clutch lever - which of those are the "lock" nut, and which is the "adjust" nut?

Sorry for asking what might seem like silly questions, but I've NEVER worked on a clutch before, and like I said, the workshop manual I've ordered have not yet arrived

[Bob_Roller]

Going by the picture, if it even is an R65 transmission, its a pre-'81 so it looks like the procedure is the same. At the clutch lever, the round nut is the lock or jam nut, the adjustment is made on the other threaded part that threads into the control housing.

[xeffer]

Im assuming you are talking about the picture in the previous thread (http://suraklyn.com/yabb/YaBB.pl?num=1171572634), where "A" and "B" are the 2 nuts on the lever and "C" is the length (201mm) the cable should be adjusted to... By the way, I didnt post that pic, and dont know whether it is a R65 Tranny or not, but it IS a useful pic if all the person wanted to do was explain between which 2 points the 201mm should be measured..

Anyway, let me see if I get this... Set "C" (at the clutch-side handlebar) so that it meassures 201mm. Then use nuts "A" and "B" to adjust the freeplay at the handlebar lever to 2-4mm.

My bike is a 1979 R65 - I've heard that the 201mm setting only applies to bikes made after 1981. Was I misinformed, and is there a different length (ie: NOT 201mm) that must be set for bikes made before 1981?

[Bob_Roller]

That's the procedure that I have seen for quite some time now, and I don't know if it is applicable to pre-'81 bikes, as I have an '81 model year.

[xeffer]

Thanx Bob, I have Thursday off. If I dont have my manual by then, I will try it and see what happens. Otherwise I will have a look at the manual as soon as I get it. I've searched the internet, but all I can find is the procedure explained above - so I'm guessing that either the adjustments are the same for pre-81 bikes, or my internet searching ability is lacking somewhat (not impossible!!)

Will let you know here how that works out
Tiaan

[Semper Gumby]

Hi xeffer

Yes The 1981 procedure works on the 1979 and the 1980.  See the other post again

TTFN,

[xeffer]

Thanx Semper Gumby for the info, I have tried the settings as you've described it in the previous thread (link posted somewhere above), and it did the trick - took less than 5 minutes as well. But.... and this is a big but, I have another problem... I would make the settings perfect - exactly 201mm at the rear with exactly 3mm play in the front. I would then ride to work (about 4/5 miles) and things would be fine. But after a hard day's work, when I get back on the bike to ride home, the play would get progressively worse during those 4/5 miles back home to such an extent, that when I get to my driveway, the clutch only JUST engages. At first I thought that I forgot to fasten the lock nut at the rear, and that it had set itself out again, but after resetting it this morning, the same thing happened again on the way back home...

Any suggestions...?

[Bob_Roller]

That sounds a bit out of the ordinary ! Is it safe to assume that you had no clutch problems before the adjustment was made ? When the clutch starts giving you problems, is there excessive free-play at the clutch lever ? When you re-check the adjustment, is it off, and in need of re-adjustment? I don't really have any good idea of what the problem may be, just looking for something that may narrow the possibilities. I had a clutch cable start fraying at the swag-ed cable end at the clutch lever, and it kind of sounds like same scenario.  

[nhmaf]

As far as I know the adjustment procedure should be the same for all 5 speed airhead transmissions.
Now, if it seems to be working & adjusted properly, but then goes out of adjustment, something is
definitely wrong.  If you are SURE that there isn't a problem with the locknut at the handlebar lever,
or where the clutch rod pushes into the rubber bellows at the back of the tranmission, something else is
mucking up your effective cable length -
-  Make certain that the cylindrical end of the cable which goes into the clutch lever on the handlebar is
properly seated and that it pivots smoothly while your squeeze the lever - If there is a burr or rough spot
in the lever it can hang up and stack stuck - resulting in the cable bending sharply at the end and eventually
fraying and breaking..
- Make certain that the clutch cable is staying fully seated in the housing boss that it mates to, and that the cable
itself isn't getting pinched in there (this is where you see the rubber accordion "boot" for the cable at the bottom
of the photo.
- If  none of the above - you *might* have a problem with the bearing or piston that the clutch rod pushes on at the
back of the transmission, but I wouldn't think it would recur so rapidly as this.
I'll keep my fingers crossed that it is something simple.

[nhmaf]

I forgot to add -
when it seems like the cable is out of adjustment.. what is the measured distance of
the reference length (which you had previously set to 201mm) ??

[xeffer]

Let me quickly tell the whole story. I was on my way to work when I noticed that every time I pulled the clutch lever, I had to pull it a little further in order to engage the clutch - as if the clutch cable is getting a little longer/stretched every time I use it. My first though was that the cable is fraying and rapidly on its way out. I removed the cable and inspected it, but couldn't find anything wrong with it. Just before putting it back, I measured it, and it measured exactly 1386mm - which is the correct length. That was when I started this thread, asking about the settings, to make sure that I put it back correctly. After following Semper Gumby's instructions, all was fine, and I thought that all that had happened was that somehow the cable had set itself out of whack during the ride. Although this DOES seem to be the case, there is obviously something wrong as it is setting itself out of whack every time on its way home from work...

The only thing I can think of is that maybe the lock nut thread is stripped (although it doesnt FEEL that way, but I havent inspected it that closely..)

Just a thought - could it be the splines? I dont know when last they where lubed, and its been one of my "jobs to do as soon as I find the time..."

[xeffer]

nhmaf,

I will check the 201mm length tomorrow before going to work, the bike is "out of adjustment" at the moment, but its is 1 o'clock (AM) at the moment here in South Africa. I'll measure it before I go to work and let you know about that.

Thanx for the input so far though

Tiaan

[Semper Gumby]

xeffer -

Check to see if your clutch cable is about to fail and check the "c" distance when yuo get home.  Usually where it breaks is at the clutch handle when the post on the end of the cable stops rotating due to LACK OF PERIODIC LUBRICATION (blame previous owner here) The cable flexes and eventually breaks (one strand at a time).  You wont be able to see this very well because the end is inside the clutch handle.  (Some disassembly require) If it is not this then possibly the cable is old and stretching - get a new clutch cable.

I use a little Wurth Pentrating lubricant on the ends but not the cable itself.  I think the clutch cable has a nylon or teflon liner which does not like todays cable lubricants.  Somebody else chime in please.

Believe it or not - I carry a spare clutch cable in my pannier bag.

The only other thing between your clutch handle and your clutch is the thrust bearing on the back of the tranny and the clutch actuating rod inside the tranny input spline.  How these could relate to your symptoms is beyond me.

BTW - I use ~203mm for the "c" distance and about 1-2 mm of play (what feels right to me) at the handle.

Good luck.

[xeffer]

OK - Just a recap... While the clutch was "out of adjustment", I measured the "201mm" length again, and it still measured 201mm. I checked the lock nut at the handlebars, and it most definitely is not stripped - the fact that the rear still measures 201mm confirms that the lock nut is in tact. OK - so on to the rear... The lock nut at the back also seems fine, so I tried to set it once again (at the rear) to make up for the extra free play I've acquired the previous day, but guess what - this time NO amount of setting would take up any free play. It would seem what had happened all along is that it didnt set itself out, but something is deteriorating and the setting is just a temporary fix. Let me explain it differently... At first I though that the nuts (at the rear) where one sets the free play, where physically moving/turning during the ride, causing the free play to become more. Now it would seem that this was not the case, I would screw the nut in to take up the free play, but during my ride, this nut would stay in exactly the same place, while the free play gets progressively worse. All that I did, was keep screwing that nut in a few turns, until it had now reached its limit - that is to say, I cant screw it in any more. It would seem that something inside was/is gradually deteriorating, and all I did was keep taking up the slack the deterioration was causing

Apart from normal clutch wear (as this happened over a few days, rather than months), ar there any other suggestions..?

PS: I DID check all the points relating to the cable. Cable does not seem to be stretched. It IS seated properly at both the lever and at the rear. It is not pinched anywhere. The problem is most definitely at the rear somewhere IE: bearing, push rod, or the clutch itself (these are my 3 guesses with my VERY limited experience/knowledge)

[Bob_Roller]

It would seem that you need to remove the rubber boot at the back of the transmission, and remove the piston, bearing and push-rod to see if one these is causing your problem. Though not too common, it's not unheard of, to have the ball bearing come apart, hopefully it's a quick and cheap fix.