1979 clutch problem.


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Silver
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1979 clutch problem.

Post by Silver »

After checking the search section it seems that the majority of clutch problems are when the bike is first started and cold, however mine is the opposite. When first started the gear selection is fine but as the engine warms up it becomes more and more difficult to change gear, especially changing down. Down shifts are easier if the throttle is blipped. The clutch plates look like original and not cheap aftermarket . I have tried three different grades and types of oil with no difference. The clutch plates are within specs and although there is some wear on the clutch drum it is not to a point where I would think that the plates are binding. The cable is good and the adjustment is correct. The only slight problem is that there is some (very little) play in the six rivets that hold the clutch drive gear to the clutch drum (basket).

steve murdoch icoa #5322
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Re: 1979 clutch problem.

Post by steve murdoch icoa #5322 »

I would have guessed too much heat in the clutch from slipping plates or improper cable adjustment not allowing a full disengagement.
You said you have that sorted so i got nothing.

Larry Zimmer
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Re: 1979 clutch problem.

Post by Larry Zimmer »

We will hope Dave has some good input! For me, my only thought at the moment is that the clutch is adjusted with a bit too much free-play causing a dis-engagement issue after the friction plates heat and expand a little. That's given that, as I read, the other things, such as plate thickness and flatness, etc., are within spec.
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daves79x
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Re: 1979 clutch problem.

Post by daves79x »

I had a set of clutch plates once that had been soaked in gasoline-contaminated oil. It made the clutch impossible to operate correctly and they had to be replaced. I'm working on one right now with very stiff shifting and it's not the clutch. The cases have to be split and I'll likely find damaged shift forks.

I'd do the easy thing first and replace the clutch plates - just make absolutely sure you have the current clutch adjusted correctly, including the adjustment screw down at the clutch cover. If that's off by much, correct cable adjustment won't matter.

Dave

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Re: 1979 clutch problem.

Post by Jeff Bennetts »

Did you check the metals to make sure none of them are warped or heat spotted?

Silver
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Re: 1979 clutch problem.

Post by Silver »

Thanks for the replies. The fact that changing gear is good when cold makes me think that the selector forks are O.K. The center adjusting screw is set according to the manual. There is some very slight heat spots on the steel plates so I checked to see if they were warped, even heated them but they are good.

daves79x
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Re: 1979 clutch problem.

Post by daves79x »

Then you are down to changing the fiber plates. Honda ones are NLA, but the plates TIMS sells work well, about like stock.

Dave

Silver
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Re: 1979 clutch problem.

Post by Silver »

Yes. Will order one tomorrow. Thanks again.

Silver
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Re: 1979 clutch problem.

Post by Silver »

So I found NOS friction plates at a Honda dealer close by. Actually less money than buying at Tim's plus exchange rate, plus shipping, plus customs duty and started to assemble the clutch. It was then that I found the problem. Three of the steel plates would not slide all the way down on the center hub, they would jam about half way down. I can imagine that as the hub got hot after riding for a while with the difference in expansion between the two metals they would not move at all. Again put it all together with new steel plates and although I can't road test it (-15c outside) I let it run for a long time until really hot and all seems good so far.

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Re: 1979 clutch problem.

Post by dkcape »

I have a similar problem with the clutch. When in gear it is hard to put into neutral.I did find some of the metal plates were not sliding down smoothly and changed them.The bush is protruding after filing away on the inside of the hub as it was touching.It is a lot better after doing that but still a bit hard to put into neutral,as can feel the bike wanting to go forward when in gear.Am at wits end as this the most problamatic ctutch i ever worked on.Any thoughts?

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Re: 1979 clutch problem.

Post by daves79x »

Yes, exactly what I was dealing with on a '79 recently. Finally installed all-new steels and fibers and that 99% solved it. Every once in a great while, the bike will still want to creep ahead while in gear with the clutch in, but way better than before and neutral is mostly easy to find again. I think that these inner and outer baskets are getting pretty worn on some bikes and the steels are cocking and hanging up a bit. Something's causing it as I've seen it on several and have heard of the problem on many others.

Dave

Silver
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Re: 1979 clutch problem.

Post by Silver »

Well after getting out on the bike a few times the clutch is working really well hot or cold, no problem getting neutral so it was the steel plates after all. Makes riding the bike so much more enjoyable.

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