High RPM clutch issue

[Incubus]

I could learn to live with this, since it is not an issue that affects most everyday riding, but I don't want to.

Incubus, my XS1100F, has a clutch issue. While the clutch grabs fine off the line and also grabs real well at the lower end and though most torque ranges, it tends to slip at high rpm. I'm talking 7500 rpm and up. This upper range is accessed rarely in regular riding, but that's where I keep the adrenaline. I like to be able to get to it when I want.

I have another complete clutch in good condition, so I could do TC's extra steel plate mod. I also could order new stock, barnett or heavy duty clutch springs and probably fix it. However, I like the softer clutch feel that comes with regular stock springs. I have heavy duty springs on my other XS1100F and I am not fond of the workout my left hand gets.

When I got the bike running last summer I checked the clutch pretty thoroughly. The friction disks were well within spec and the clutch springs measured as if they were new. I do not know if the steel in the springs loses some of its springiness over the years.

I also use standard dino type oil.

What is the most likely way to fix this issue without making my bike less pleasurable to ride?

Thanks, y'all.

Patrick

[Ken Talbot]

How about a hydraulic clutch?

[cywelchjr]

I could learn to live with this, since it is not an issue that affects most everyday riding, but I don't want to.

Incubus, my XS1100F, has a clutch issue. While the clutch grabs fine off the line and also grabs real well at the lower end and though most torque ranges, it tends to slip at high rpm. I'm talking 7500 rpm and up. This upper range is accessed rarely in regular riding, but that's where I keep the adrenaline. I like to be able to get to it when I want.

I have another complete clutch in good condition, so I could do TC's extra steel plate mod. I also could order new stock, barnett or heavy duty clutch springs and probably fix it. However, I like the softer clutch feel that comes with regular stock springs. I have heavy duty springs on my other XS1100F and I am not fond of the workout my left hand gets.

When I got the bike running last summer I checked the clutch pretty thoroughly. The friction disks were well within spec and the clutch springs measured as if they were new. I do not know if the steel in the springs loses some of its springiness over the years.

I also use standard dino type oil.

What is the most likely way to fix this issue without making my bike less pleasurable to ride?

Thanks, y'all.

Patrick

Are you using oil marked at "energy saving"? If so that might be the problem. The only advantage I have seen for MC specific oils is that they are formulated for wet clutches, and don't have the energy saving additives that tend to make clutches slip. Frankly I'm thinking about trying (once I get past this forking crisis ) MC specific Mobil 1 as it says it's formulated for wet clutches. They carry it at O'Rielys/Kragen Auto parts stores, it's about $10 per quart which is just slightly more than the auto stuff. I'll take any reduction in friction I can get that doesn't result in the clutch slipping.

Oh, and the high RPMs are exactly where clutch slip will happen as the torque curve continues to rise with RPMs. I know that they make special racing clutches for cars that actually increase the pressure plate engagement pressure with RPMs for that very reason, we are not alone in that problem.

[Incubus]

I have been thinking very long and hard about the hydraulic clutch mod, Ken. I really like the feel of the hydraulic clutch on my '87 Shadow. That doesn't address the issue of whether I need new springs or should add a clutch steel. Which measure would most likely fix the slipping issue?

I really don't think it is the oil. I use the same oil in all my bikes (six runners) and this is the only one with this issue.

The hydraulic clutch conversion really looks pretty easy. That could well be my next project.

Patrick

[planedick]

Shim rings

I purchased a bag of 12x18x1 mm shim rings from McMaster CArr (mcMaster.com) there was 50 in the bag for i think around $5. I placed 2 behind each sprong and solved the problem. If you can't find them I could send you some.

[trbig]

The thing with either the heavy duty springs like Barnett (MUCH better than stock heavy duty) or the extra steel plate in there, is that both are going to firm up the handle pull. I was putting in new springs about every 6 months with the OEM "Heavy Duty" springs. The jury is still out on the Barnett Springs and how long they'll last me, but they've been rock solid on hookup so far.


Tod

[Larrym]

Friction Co-efficient

Patrick,

While you're evaluating different mods and looking at your left hand :



When you do take the bike out of service and go invasive be sure to look again at the friction plates/steels. I know, you've been there before, but check for signs of glazing, overheating, or warpage in the steels.

Thing is that any of these will result in the clutch slipping a bit at the RPMs you described. Then the slipping only continues to get worse as more and more area gets glazed.

If there's enough material left on the friction plates then it's possible to de-glaze them along with the steels with a little sandpaper. Following reassembly a careful break-in period might get you back to normal performance and keep you there.

No need to mod the bike and develop a gorilla grip unless there's no other option.

JAT.

[psycoreefer]

another member, justjeff posted a while back about Alto clutch frictions with stock steels, the alto frictions are thinner then stock so you get to use an extra friction and an extra steel and stay with the stock overall thickness and stock springs for a stock feel. He runs them on his turbo and doesn't have problems, I've ordered from him and I'm going to give them a try as my clutch is doing the same thing yours is.