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77 RS clutch slipping

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schrader7032
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Re: 77 RS clutch slipping

Post by schrader7032 »

That does seem weird!

In the end, all of the "techniques" don't really matter. With all things considered, we know that as you pull the hand lever in you go from clutch full engaged (plates all together) to a point where the clutch is fully disengaged (plates apart). You want it so that when the hand lever is at rest, the clutch is engaged and with the lever pulled all the way back to the bars, the clutch is disengaged. You don't want it so that the moment you pull the lever, the clutch begins to disengage and you don't want it so that with the lever all the way back, the clutch is still engaged. So, there's a "sweet spot" in the middle that you're trying to find. It doesn't have to fit any of the methods...it just has to work and shift like you expect and want to feel. So you can use as much free play as you want to get that sweet spot right in the middle of the hand lever throw.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

jimcarrr100rs
Posts: 80
Joined: Sun Oct 13, 2019 2:47 pm

Re: 77 RS clutch slipping

Post by jimcarrr100rs »

I agree. Also when the lever is fully released and there is free play the clutch should not slip.
I put it back together and will ride it tomorrow.
Jim
77 & 83 R100RS, 56 R69, 74 R90/6

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Randolph
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Joined: Tue Jan 13, 2015 11:31 pm

Re: 77 RS clutch slipping

Post by Randolph »

Clutch slippage at speed and under load also sounds like spline grease getting spun onto the clutch disk material. Don't use wheel bearing grease. Use a grease that will stay put and use it SPARINGLY. I use Molykote M77 grease.
Clean the splines of both parts squeaky clean then brush a TINY amount into the splines of both parts. Brushing the grease in is important. Then push the disk onto the input shaft and clean off any excess that gets squeezed out with a q-tip. I even reverse the disk and push it in again to make sure there isn't any excess that will get slung onto the disk.
Good luck,
Randy

jimcarrr100rs
Posts: 80
Joined: Sun Oct 13, 2019 2:47 pm

Re: 77 RS clutch slipping

Post by jimcarrr100rs »

Randy, Thanks for they reply. I use Guard Dog spline lube and have been very careful about it.
Went for a ride this morning and it slipped. I was going 75 in 5th and did a hard roll on. When it got to 5K it let loose. Got home and checked free play good, pulled the clutch arm, piston, bearing all good, was able to move the rod in and out with no hang up. I guess I have to pull it apart and measure the depth of the flywheel so if anyone has one to measure and let me know I would really appreciate it.

Jim
77 & 83 R100RS, 56 R69, 74 R90/6

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cbclemmens
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Re: 77 RS clutch slipping

Post by cbclemmens »

Did you resurface the flywheel? A glazed surface on the flywheel can cause the clutch to slip when everything else is good.

Craig

jimcarrr100rs
Posts: 80
Joined: Sun Oct 13, 2019 2:47 pm

Re: 77 RS clutch slipping

Post by jimcarrr100rs »

Craig, Thanks for the reply but airheads do not use the flywheel as part of the clutch. You just use it to bolt everything to it.
77 & 83 R100RS, 56 R69, 74 R90/6

jimcarrr100rs
Posts: 80
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Re: 77 RS clutch slipping

Post by jimcarrr100rs »

So here is what I have. I found my 2 flywheels hiding behind some old valve covers. One from my 70 R7 5/5 and it measured .650 to the spring perch. The other is from a 76 R90 and it measured the same. My 77 measures .675 or 25 thousand more than the other two. So is that enough to cause slipping? Clutch disc measured just over 6mm, spring at 17.8mm.
Thanks, Jim
77 & 83 R100RS, 56 R69, 74 R90/6

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Randolph
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Re: 77 RS clutch slipping

Post by Randolph »

I did a quick check on the MAX website and the P/N for a '77RS flywheel is 11 22 1 336 380 (to 09/80). The P/N for a '76 R90 flywheel is 11 22 1 262 070 (from 09/75). And, of course, no dimensional info. So it's apples and oranges.
I would take your question to Tom Cutter at the MicaPeak.com Airheads list:

https://lists.micapeak.com/mailman/listinfo/airheads

or

www.RubberChickenRacingGarage.com


If anyone knows flywheel dims Tom does.

Randy

jimcarrr100rs
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Joined: Sun Oct 13, 2019 2:47 pm

Re: 77 RS clutch slipping

Post by jimcarrr100rs »

Looks like the difference between them is the timing mark
77 & 83 R100RS, 56 R69, 74 R90/6

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Randolph
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Re: 77 RS clutch slipping

Post by Randolph »

You could install the '76 flywheel and even if the slippage goes away you still won't know the "why" there's the 0.025" difference.

Ask Tom.

Randy

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