Clutch adjustment needed once warmed up

LPYYZ

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I've read a lot of different posts on clutch adjustment problems and experimenting with different push-rods etc.

Has anyone come up with a reasonable solution?

When it's cold outside or the bike isn't too hot the 1/8" free play at the lever works great. After my bike warms up it will creep forward at a stop in first gear with the clutch lever pulled in (i.e. the clutch is not fully disengaging with the lever pulled).

I then have to adjust the free play at the lever until this stops which leaves me with about 1/4" (or usually more) free play at the lever base. I'd be okay with that but unfortunately with 1/4" free play the clutch now isn't engaging until the last few millimeters of clutch release which makes riding a bit more difficult and I'm now worried that the clutch isn't fully engaged with the lever released.....there is no happy balance at that point.

Once the bike is shutdown and cools off I have to adjust it back to 1/8" or less free play like the manuals say and start the whole procedure over again.

I bought new drive and friction plates, new cable and checked the cable routing. I replaced the springs and conical washer etc. I double checked all the work and adjusted the clutch at the engine case multiple times to ensure it was correct.

By this time it was almost winter and the outside temperature was around freezing. The bike ran great and I never had to adjust the clutch on my short 20 minute rides. We had a few days above freezing so I took the bike out for a long ride and once again the clutch problem showed up in the warmer weather/longer ride.

I know it's related to engine temperature in some way but I'm at a loss as to how it can be fixed.

Any suggestions would be appreciated.


Liam
 
I tend towards the 1/8 turn back off/ freeplay at the screw on the case. Not all clutch cables are created equal some cheaper ones stretch, or have poor quality or no anti-friction liners, cables are not prelubed when new. Did you slightly straighten the elbow at the housing? Try a completely free no bends (ie not under the gas tank) cable routing as an experiment, see if that changes your cold hot dilemma. Many replacement cables are the long "special" cables they will not work well with shorter bars and "factory" routing. I have a thread on an alternate routing to make a long cable work well with short bars.
 
I've been running a 1-piece 7075 alloy pushrod since last year. The cold/hot differences are almost gone, no need for adjustments anymore.

I intend to update the 'clutch pushrod' thread later, after some more miles and time, to see how well the dimpled ends are holding up, and if there's any significant wear in the bushing/seal zone.

Member DPS650RIDER runs with a 1-piece 6061 rod. Seems that he needs to replace it every couple of years or so, due to the wear marks at the bushing/seal zone...
 
My experience is the opposite. As the motor warms the gap at the clutch perch gets wider.
What adjustment do you have at the screw in the side case?
 
Yes, this a well known and well documented problem on these bikes. Its due to the different expansion properties of steel and aluminum.

2M has done a ton of research on this, and it may lead to a good solution.

I use the one piece steel push rod, because it prevents excessive wear on the bushing and pushrod seal. I used to re-adjust the clutch cable free-play at the lever as the engine warmed up, and that does work. However, a couple of years ago, I found just the correct setting for the lever free-play...........the sweet spot or holy grail had been found!

Now I no longer adjust the lever free-play, and the clutch works quite well most of the time. On hot summer days and after a few hours riding, I still have some clutch drag which can make it hard to shift into neutral.

I just don't find it necessary to shift into neutral while the engine is running. At intersections I keep the bike in first gear, which is the safe thing to do. When I pull into a gas station or other stops, I simply shut off the engine while in first gear, and then select neutral when the engine is off.
 
RG I'm not sure he is dealing with the "well known and well documented problem".
If I understood correctly he adds slack after it is warm.

I'm glad you finally were able to work yours out. Your taking your hands off the bars to adjust the clutch perch had me worried about your safety.
I'd suggest a tich tighter at one point or another to relive that drag.
Maybe I've been blessed with good clutches (as opposed to evil ones?) but I don't have problems finding neutral or creep at the lights.
 
...I found just the correct setting for the lever free-play...........the sweet spot or holy grail had been found!

And that's the most important thing. Good cable, routed correctly, everything cleaned and lubed properly, appropriate lever arm length on the clutch worm, appropriate worm arm initial angle, can get you there...
 
Another factor, of which I have no quantitative data, is the reported 'swelling' of certain kinds of friction plate compounds, like the old cork and budget plates. A few thousandths inch of clutchpack swell, when hot, can add significant extra play at the clutch lever. When I switched to Barnett plates, I noticed a reduced hot/slop phenomena...
 
RG I'm not sure he is dealing with the "well known and well documented problem".
If I understood correctly he adds slack after it is warm.

I'm glad you finally were able to work yours out. Your taking your hands off the bars to adjust the clutch perch had me worried about your safety.
I'd suggest a tich tighter at one point or another to relive that drag.
Maybe I've been blessed with good clutches (as opposed to evil ones?) but I don't have problems finding neutral or creep at the lights.

Thank you WER for being concerned about my health. However, I sometimes ride for short periods, with just one hand on the bars, just as a rest when riding on a long day. I've even been known to take both hands off the bars for a very short period.:yikes:
 
Thanks for all the suggestions.

I had the same problem prior to replacing all those parts unfortunately. The cable is from motion pro and properly lubed, very little resistance at the lever. I've run three different types of bars and different cable routing with no improvement. I replaced the drive plates with Yamaha dealer parts and the friction plates and clutch springs are from EBC.

I've tried different adjustments at the engine case including the recommended amount in the service manual.

The frustrating part is that the clutch works really well until the bike gets hot.

I'm almost convinced it's related to temperature now that I've replaced so many parts with almost no change at all.

It sounds like my next step is to explore a new pushrod. Does anyone mill a 7075 alloy rod or something similar? It seems like this is one of my last options.

Thanks again for all the suggestions.
 
"I'm almost convinced it's related to temperature":
Yes, indeed, its definitely related to engine temperature.

If you play with the adjustments long enough, it is possible to find the sweet spot,where it works reasonably well. Yes a single long aluminum pushrod may be the answer.
 
Another option to try would be to reduce the worm arm length, which would decrease your leverage ratio, making the pull a bit harder, but also reduces the relative magnitude of the expansion/slop.

I recall Retiredgentleman settled on 1.5" as his ideal length, worm center to clevis pin center.

...It sounds like my next step is to explore a new pushrod. Does anyone mill a 7075 alloy rod or something similar? It seems like this is one of my last options...

I got my 5/16" 7075 rod in 12" lengths from an online supplier, Exact Metals.
Just checked their site, "Out of Stock"...

The rods I got were slightly bent, takes me almost a full day to straighten and polish one.
That stuff is tough. Be sure your lathe bits are sharp...
 
Some years used a short arm, the cable hole in close to the worm. Some years a long arm with the hole out a ways. They also used a long arm with the hole somewhere in between.
I had a broken worm on my 75. I replaced it with the unit Mike's sells. It has a long arm with two holes. One close, one far. I tried both holes. The one in close opens the clutch more but requires a bit more lever effort. The outer hole reduces the lever effort but doesn't open the clutch as much.
I found the difference in lever effort, not so much. The more open the clutch the better.
This reduces drag, and the hot cold adjustment.
The well lubed cable and worm help a bunch.
Leo
 
Some years used a short arm, the cable hole in close to the worm. Some years a long arm with the hole out a ways. They also used a long arm with the hole somewhere in between.
I had a broken worm on my 75. I replaced it with the unit Mike's sells. It has a long arm with two holes. One close, one far. I tried both holes. The one in close opens the clutch more but requires a bit more lever effort. The outer hole reduces the lever effort but doesn't open the clutch as much.
I found the difference in lever effort, not so much. The more open the clutch the better.
This reduces drag, and the hot cold adjustment.
The well lubed cable and worm help a bunch.
Leo
Leo I have used some of the suggestions here and now have my lever pull pretty much under control. Mostly with a new Motion Pro cable and plenty lubing. Mostly what I think is left is it seems like maybe someone replaced the clutch springs with a heavy duty version. The lever snaps back if I just let go of it. Had that happen on a Honda once when somebody suggested using heavy duty springs. Put the originals back on and all was well. And the clutch still worked just fine.
 
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Member DPS650RIDER runs with a 1-piece 6061 rod. Seems that he needs to replace it every couple of years or so, due to the wear marks at the bushing/seal zone...

My first aluminum rod had that problem, the one in the bike now has a steel insert at the actuator end and eliminates the wear problem.
 
Here are some pictures, the first on is my original 1 piece rod where you can clearly see the wear marks.

The second picture is of the 2 pieces (steel and aluminum) before I put them together. Note that the aluminum piece fits inside the steel making the total length almost all aluminum to maximize expansion as it heats up.

The third is the assembled rod. I used JB Weld to keep it from moving. I was a bit concerned about the movement between the steel and aluminum interface with the JB Weld but in practice there have been no issues.

The forth shows the actuator end after final machining.
 

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My first aluminum rod had that problem, the one in the bike now has a steel insert at the actuator end and eliminates the wear problem.

Yes, that's the best solution. Saves the pushrod at the bushing/seal zone.

I've made up some 7075T6 1-piece rods, same as what I'm running now.
I have (3) available now, for those who want to partake in the experiment.

PM me if you want one...
 
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