clutch shift problems

devildrums

XS650 Enthusiast
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1977 650D - I am having a shifting issue where sitting cold it does what it is supposed to, but once it warms up it seems to not downshift or go into neutral at all. Pretty sure it needs new clutch but I am having a really hard time locating a kit, as Mikes is out until at least late February. I have found a few sets of the friction plates, so that is good, but cannot find the matching set of steel plates.

Question 1 - Is the clutch more or less the real problem
Question 2 - Do I have to also replace the steel plates, or can I reuse them? If not, any leads on finding them?

Thanks,
Jimmy
 
The clutches on these are the subject of many discussions with some having no problems to others forever making roadside adjustments, it is rarely the plates that give the trouble, but first thing first, make sure your cable is routed correctly and well lubed, if you can get a motion pro cable as these are more substantial than stock or other after market ones, then adjust as per the manuals, also make sure you are using a motorcycle wet clutch specific oil of the correct weight, then you may be one of the lucky ones that have a fully functioning clutch at all temperatures, i on the other hand was not so lucky, i also replaced the plates to no avail, upon opening up the clutch side and looking even closer it became apparent that the pressure plate did not disengage squarely, i then stripped the clutch i used my lathe to polish the mushroom and square it up, i also noticed the pressure plate had not been squarely machined new, so i done this myself to within 2 thou i also squared it where the mushroom meets the plate, the last thing i purchased a new thrust bearing from Heiden tuning that has many more rollers in it than the stock item, i put it all back together and it is now perfect at all temperatures, one more thing it is important that you use a motorcycle specific oil as car and truck oils have friction modifiers in them and this will make your clutch slip, i know this from experience.
 
The clutches on these are the subject of many discussions with some having no problems to others forever making roadside adjustments, it is rarely the plates that give the trouble, but first thing first, make sure your cable is routed correctly and well lubed, if you can get a motion pro cable as these are more substantial than stock or other after market ones, then adjust as per the manuals, also make sure you are using a motorcycle wet clutch specific oil of the correct weight, then you may be one of the lucky ones that have a fully functioning clutch at all temperatures, i on the other hand was not so lucky, i also replaced the plates to no avail, upon opening up the clutch side and looking even closer it became apparent that the pressure plate did not disengage squarely, i then stripped the clutch i used my lathe to polish the mushroom and square it up, i also noticed the pressure plate had not been squarely machined new, so i done this myself to within 2 thou i also squared it where the mushroom meets the plate, the last thing i purchased a new thrust bearing from Heiden tuning that has many more rollers in it than the stock item, i put it all back together and it is now perfect at all temperatures, one more thing it is important that you use a motorcycle specific oil as car and truck oils have friction modifiers in them and this will make your clutch slip, i know this from experience.
I am learning that the clutch can be a headache. If it was a cable problem, wouldn't it have trouble shifting from the start? I do not really know why it would only happen when it heats up.
 
I am learning that the clutch can be a headache. If it was a cable problem, wouldn't it have trouble shifting from the start? I do not really know why it would only happen when it heats up.
As it heats up you have different expansion rates of the metal components and this creates the problems some of us have had, the cable if poorly lubed will not operate properly, this may not manifest itself when cold, i can only relate my own experiences on this, but cables and oil play a large part, if i was to get another XS650 i would do the same clutch adjustments and checks as i have on my existing one.
 
Proper clutch adjustments, lubed cables and proper routing is the key to all. I made the mistake once with the lever not fully out to initially set at wormgear. Final freeplay adjustment went out the window and was wondering why?? Tried it again, and have not touched it since.
 
Proper clutch adjustments, lubed cables and proper routing is the key to all. I made the mistake once with the lever not fully out to initially set at wormgear. Final freeplay adjustment went out the window and was wondering why?? Tried it again, and have not touched it since.
Well, have the chain lubed and all of the components greased and it rode a little farther, but then would not gear down. My cable used to hang out pretty far to the right, but then I clamped it to the center bar so it would not be pulled or pinched by the tank. Could just that change make it not work properly? I'm thinking it is just time to replace the clutch plates and change to the long push rod.
 
You added this "clamping" where the cable runs under the tank, correct? If so it shouldn't effect things much, unless in doing so you made any of the bends tighter.
As you pull the lever the cable stretches a bit. This happens whatever you do. Anything that increases the resistance to the cable sliding inside the housing increases the stretch. This extra stretch will not move the pressure plate as much as it should.
This cause the clutch to drag a bit more than it should. This extra drag makes finding neutral and shifting harder.
The bikes come with metal straps for holding the harness and cables I place. These stock Clamps are not very tight. This allows the cable to move a bit. This is ok, This movement allows the cable to straighten out so as to minimize the binding of the cable.
As others have said, A well lube cable and worm make ting work well.
The way you lube the cable and the lube you use has an effect on the way it works.
One of those things that clamp around the cable then you hook a spray can lube to it. Not the best way.
This lube won't last long and is a poor lube.
Use motor oil and use the kitchen foil funnel method as described in the repair manual.
I have a spare cable. I keep one oil lubed this way. Then when the cable needs lube I can just sap in the fresh one. I then can lube the cable I took off to have for the next time. This minimizes the bikes down time.
Leo
 
You added this "clamping" where the cable runs under the tank, correct? If so it shouldn't effect things much, unless in doing so you made any of the bends tighter.
As you pull the lever the cable stretches a bit. This happens whatever you do. Anything that increases the resistance to the cable sliding inside the housing increases the stretch. This extra stretch will not move the pressure plate as much as it should.
This cause the clutch to drag a bit more than it should. This extra drag makes finding neutral and shifting harder.
The bikes come with metal straps for holding the harness and cables I place. These stock Clamps are not very tight. This allows the cable to move a bit. This is ok, This movement allows the cable to straighten out so as to minimize the binding of the cable.
As others have said, A well lube cable and worm make ting work well.
The way you lube the cable and the lube you use has an effect on the way it works.
One of those things that clamp around the cable then you hook a spray can lube to it. Not the best way.
This lube won't last long and is a poor lube.
Use motor oil and use the kitchen foil funnel method as described in the repair manual.
I have a spare cable. I keep one oil lubed this way. Then when the cable needs lube I can just sap in the fresh one. I then can lube the cable I took off to have for the next time. This minimizes the bikes down time.
Leo
Thanks for the insight. I did use 10w30 oil to lube it and it did go all the way through the cable. Pulling on it by hand was so much easier. The only problem I can tell now might be when it bends around the carb and goes down into the motor. The little bent metal piece that attaches the cable to the block might be causing a problem, otherwise I don't see any routing that is different from my friends xs. And like I said, it really works fine until it heats up, and most of you guys posts tend to make it lean toward the clutch plates as the problem at that time. I am trying to find a simple fix, but maybe i need to just break down and spend the money.
 
What you're describing sounds like an adjustment issue, as in not adjusted tight enough. One of the big issues with this clutch set-up seems to be related to expansion of all the parts when things get hot. The alloy engine cases expand more than the steel pushrods between the clutch and the worm where the cable attaches. This adds freeplay which means the clutch plates don't get pushed apart as much as they did when things were cold. This can make them drag more and that can make shifting and finding neutral harder.

So, what most of us do is set the clutch adjustment a bit tighter than the book calls for. The book says turn the worm adjusting screw in until it makes light contact, then back it off about 1/4 turn. We only back it off maybe 1/8 turn, and I turn it in until it makes pretty hard contact before backing it off. I also employ a technique I call "fanning" the clutch lever as I adjust the worm screw. I work the clutch lever in and out through it's freeplay range. I don't pull it all the way in and disengage the clutch, just through it freeplay range until it hits up against where it would start disengaging the clutch. What this does is stack all the clutch pushrods and little balls tightly together, pushing any oil out from between them and eliminating any spaces. If you work the clutch lever like this as you continue to tighten the worm adjustment screw, you'll often find you get another 1/4 turn or so in on it. Only after doing all this do I back it off that 1/8 turn.

And I should mention, all this clutch adjusting should be done with the adjuster up at the lever screwed in all the way, putting as much freeplay in the lever as possible. The whole point is to try and do as much of your clutch adjusting with the screw down at the worm, then just fine tune and finish up with a small adjustment up at the perch.

And one final and important point - do this adjusting on a cold motor. I don't consider setting it like this too tight because as soon as you start the motor and it begins to heat up and expand, more freeplay will begin to develop.
 
What you're describing sounds like an adjustment issue, as in not adjusted tight enough. One of the big issues with this clutch set-up seems to be related to expansion of all the parts when things get hot. The alloy engine cases expand more than the steel pushrods between the clutch and the worm where the cable attaches. This adds freeplay which means the clutch plates don't get pushed apart as much as they did when things were cold. This can make them drag more and that can make shifting and finding neutral harder.

So, what most of us do is set the clutch adjustment a bit tighter than the book calls for. The book says turn the worm adjusting screw in until it makes light contact, then back it off about 1/4 turn. We only back it off maybe 1/8 turn, and I turn it in until it makes pretty hard contact before backing it off. I also employ a technique I call "fanning" the clutch lever as I adjust the worm screw. I work the clutch lever in and out through it's freeplay range. I don't pull it all the way in and disengage the clutch, just through it freeplay range until it hits up against where it would start disengaging the clutch. What this does is stack all the clutch pushrods and little balls tightly together, pushing any oil out from between them and eliminating any spaces. If you work the clutch lever like this as you continue to tighten the worm adjustment screw, you'll often find you get another 1/4 turn or so in on it. Only after doing all this do I back it off that 1/8 turn.

And I should mention, all this clutch adjusting should be done with the adjuster up at the lever screwed in all the way, putting as much freeplay in the lever as possible. The whole point is to try and do as much of your clutch adjusting with the screw down at the worm, then just fine tune and finish up with a small adjustment up at the perch.

And one final and important point - do this adjusting on a cold motor. I don't consider setting it like this too tight because as soon as you start the motor and it begins to heat up and expand, more freeplay will begin to develop.
Thank you 5twins for all of the information. I am going to go through and do all of this tomorrow and hopefully it dials it in.
 
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