Topic: Clutch slip

[BobbyR]

What kind of oil or additives(if any) are you using?

Oh, no!

I forgot it was loaded. 

[BobbyR]

I dont have a clutch adjuster, im using an aftermarket clutch lever that really doesent fit that well and i had to remove some stuff (adjuster etc..) just to get it to fit. This could very well be part of the problem, i just thought it was wierd that it would only do it cold. 

I think this may be your problem. My neighbor has a Yami and he tore down the clutch twice, springs and the whole nine yards. Turned out to be the slave cylinder was gunked up. In your case the clutch my not be fully engaging and the parts finally expand whenit gets hot. Honds handle asseblies are pretty easy to come by. Oil like women is a matter of preference.

[nteek754]

Replace the clutch and adjust to specs under the clutch cover and then fine tune it down at the cable clutch end my 70 836 was slipping in all gears till it warmed up new clutch no problem. have fun Craig in Maine

[kpier883]

Kpier, it broke from uneven tightening, not lack of torque wrench...

You may be right.  I still won't tighten it again without a torque wrench.  I am usually amazed at how "loose" the proper amount of torque actually is on these motorcycles.

I think this has a lot to do with the fact that when I first started turning wrenches, it was on Ford F600s, Mack R600s and Caterpillar 950 and 966 articulated loaders, John Deere tractors and such.  No aluminum involved and things had to be really tight.  Try breaking head bolts loose on a six cylinder mack engine, or torquing them down.  Lots of pipes over the end of pull levers.  A dredge pump with 12 inch suction and 8" discharge could take two people to tighten some bolts with a 6 or 7 foot wrench.

I just don't have a good "feel" for the proper torque when the fasteners and parts are small and fragile.  So I learned my lesson and started using the torque wrench when possible.

[Tower]

@motomotard, to get the symptoms of clutch slippage when cold but not when hot, two factors must come together. 
1) Clutch adjustment is too tight.
2) springs are not correct spec (too long and possibly too weak)

First, and without delay, set your adjustment correctly (1/4 turn out, even 1/8 turn is better than none).  Set too tightly, and clutch wear is very rapid.  The damage, by a wide margin, is greater from overtight than from clutch bounce.

Second, my guess is your springs are too long as this shows up mostly on a cold clutch when tolerances are at their tightest.  All it takes is 1/16" to make a big difference.  (If springs were too short, the clutch would be easier to engage cold and would be difficult to disengage when hot).  Make sure all your clutch parts are compatible for the specific clutch on your bike.  i.e  your set of plates and springs must match the hub and basket specs.

[fuzzybutt]

i'd been having the same problem with my 74' 750k, stock clutches. did all the proper adjustments, new cable, springs within spec. i never would have thought the problem might have been the oil i was using. i got a deal on a case of yamalube 10/40 this past summer and i've been changing the oil every 1000 miles or so with it. changed the oil and filter today BUT because i was finally out of the ysamaha oil i went down to the local autozone and got a gallon of 15/40 rotella t. the difference was immediate and amazing. the clutch grabs like it should cold or hot, ALOT less noise in the motor too. shifts smoother even. not trying to turn this into an oil thread by the way

[Patrick]

I've had it with crappy aftermarket clutch fiber disks and decided it's time to stop #$%*ing around and spring for Honda parts. I've saved $15 on so many sets of crappy disks that I figured by now I've saved enough to buy the right ones.

When, however, is it necessary or recommended to replace the steels? I have six or seven sets of steels disks. All appear to be in decent shape, i.e. there is no warpage, but all have some amount of corrosion or the polishing of age. Which are the critical parts of a good operating clutch? Will I be unhappy if I get fibers alone?

I really need to do both of my 750s. The clutches don't slip off the line and they don't seem to break off at high rpm. They don't rattle or vibrate when they engage. But the clutches on my other bikes just seem to grab with more authority and the engine speed on the other bikes ('87 VT1100, '79 XS11 - more powerful bikes, granted) more closely approximates the torque experience, if you know what I mean. Am I just expecting too much out of K0 and K5 clutches?

Patrick

[FunJimmy]

Patrick

Your manual will give the specification for acceptable tolerances regarding flatness.

I went to a local glass shop and purchased an 18”x18” piece of ½” thick glass.
With the glass on the bench and a beer by my side, I use 220 wet aluminum oxide paper, back down. Wet the paper well on both sides. This will hold it to the glass while you hone each side of the metal discs. Hone in a circular pattern and your will quickly see where the high spots (warp) are.

It doesn’t take very long to get them nice and flat as well as removing the glazed finish. Remember to dry them well and apply a light coating of oil. The discs will rust if left
un-coated until re-assembled.

That piece of glass and wet sand paper can also be used to hone flat head gasket surfaces and all kinds of other simply procedures. It’s well worth the cost of having a piece cut.

Cheers
Jimmy