Yet Another Slipping Clutch Thread

I have found another source of slipping clutches that I haven't found any mention of. I have noticed that the amount of free play in my clutch varies a bit with load and also depends on the gear I am in. If I am cruising in 5th the free play is the same as when I am stopped. Under a load in 4th the free play mostly disappears. There do seem to be effects in the lower gears but I never stay in them very long so did not experiment that much with them.

What I suspected was happening was the transmission shaft walking a bit from left to right. I had noticed this issue a couple seasons ago but with heavier than stock springs and plates in good shape it was not a problem so I forgot about it. My engine has quite a bit more torque than stock so no surprise with the need to beef up the clutch.

I started having issues with it slipping under heavy load again so in the process of fixing up the clutch I investigated the changing free play. My first suspicion was play in the main ball bearing which serves as the thrust bearing on the trans input shaft. I checked that and it's basically like new, my bike has a lot of miles on it but the trans was replaced a few seasons ago with one in just about perfect condition so no surprise.

When I pushed and pulled harder on the shaft I could feel a bit of movement and upon close inspection I could see that the bearing was moving in the case a bit and that was the cause of the motion. Since the riding season is getting close to the end and I knew I could stop the slipping by working on the clutch (roughing up the plates, using a combination of thicker early plates and stock plates to get the correct installed height for the springs) I did that and have no more problems with slipping.

So I have been thinking about ways to fix this over the winter, one thought I had was putting a bit of Locktite in the groove where the bearing retainer ring fits into the case. Any other thoughts on this?

Seeing this problem makes me wonder if there are other bikes out there with similar problems...

See this.
http://www.xs650.com/threads/magura-clutch-lever-and-aluminum-pushrod.56574/
And this.
http://www.xs650.com/threads/interest-in-8-plate-clutch-conversions.56486/

You can use sleeve retainer and you can also use a punch to raise the metal in the bearing recess. Not a great fix but might save an old case.

dps650rider said:

putting a bit of Locktite in the groove where the bearing retainer ring fits into the case.

Click to expand...

Loctite sells a product specifically for retaining bearings https://www.tryloctite.in/products/retaining-compounds/
But.... the hole is not worn round (it never is) the trick(s) is having the bearing centered while the compound sets and is it strong enough to hold where the aluminum casting didn't?

It looks like the wear in the hole is minimal, when cold it takes quite a bit of force to move the bearing. When it gets hot is when the problem shows up, I think it wouldn't take much to stop this and any misalignment would be too small to make any difference.

Cases are apart and I got some Loctite 620 to put between the bearing and case. Was thinking about just putting it in the upper case so it won't make it hard to take it apart later. Splitting the case is hard enough already.

Been contemplating dimpling it a little as well...

Recommended installation of the bearing retainer ring is to have it span both case halves. That would introduce disassembly problems later if it's locked-in with 620.

Is the bearing retainer ring loose in the bearing groove?

Is the bearing retainer ring loose in the case grooves?

Retainer ring (1 solid ring on this bearing) had about 0.005 slop in the bearing, a couple days ago I locktited the ring in the bearing groove while applying pressure in the direction the clutch pushrod would apply pressure. Didn't measure it but I believe I have a similar amount of slop (maybe a bit more) where the ring mates with the case. so sum total slop when hot is 0.010+ which is definitely enough to change the free play.

So my thought is to put some locktite in the ring groove and at least part of the surface area where the bearing fits into the case in the top half of the case only since it is assembled inverted. I did assemble the case halves with the trans input shaft installed and after snugging 2 case nuts on either side of it I can detect no motion. This problem was occurring when up to operating temp after the case expands. I was also thinking about roughing up the outer race a bit (maybe some shallow scratches made with a dremel so the locktit has something to grab onto.

Honestly I'll bet mine is not the only 650 running with this issue, just others may have not noticed the change in clutch free play when applying torque and then spent the time figuring out the cause.

Assembled the case yesterday putting locktite in the top case only so it won't make splitting the cases any more difficult. I did a test of the locktite on a couple pieces of metal letting it sit a few days and gently heating it a few times so it would cure. Didn't take much effort to get it apart. With the snug fit of the bearing race in the case that will likely be more difficult to take apart if I ever need to but certainly think it would be doable.

If the time ever comes when I need to do that and I can't get it apart I always have another engine case.

All back together and no more changes in freeplay. The locktite did the trick.