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1971 R75/5 Grabby Clutch

jimmiejag

New member
I have finished a significant amount of work bringing back my R75/5 from a number of years off the road, including a valve job, new rings, replacing most rubber parts, rebuilding both Bings, new coils. plug wires and plugs, solid state voltage regulator, new AGM battery, new starter, etc. Now that I have been able to start putting some road time on it, I find the clutch grabs quickly as I let out the lever. I have it adjusted so the friction point is at a good spot on the lever, allowing an inch or so release before the clutch engages, but when it does engage, it does it more abruptly than my previous R75/5 did. My buddy thinks it may improve as I use the bike. I hope I don't have to tear into it further to replace the clutch.
Any opinions about whether the clutch will engage more smoothly as I put some miles on it? (It probably has the factory OEM clutch, with around 30,000 total miles on it.)
TIA
 
I would suggest checking and greasing the throw-out assembly, then doing a proper clutch adjustment. Also, a grabby clutch, in my experience, may indicate dry. rusty input splines, so a spline lube may help.
 
We'll Try It Again

We used a special-made gauge to measure the proper distance, as indicated in the proc noted in this thread. To be sure, we'll go through it again. I am afraid the clutch has foreign matter on it, like oil or grease. Of course, that means a clutch replacement will be needed. I'll try to get a few more miles on the bike and see if it gets better (if the problem is, for example, rust on the splines, it may improve with use) but I am likely facing a clutch replacement = $$$. I'll follow-up later.
 
Rust on the splines

If you think you may have rust on the transmission input shaft splines, then they are dry. If they are dry, then they are wearing faster then they should be with not only the clutch plate sticking on them.

I realize it is a pain to get to the input shaft but personally, I would not keep riding until it is checked and lubed. A day's worth of work taking things apart and checking/correcting a problem can save big bucks down the road.

Not saying the splines will fail or are necessarily dry, but if they are dry, why subject them to more wear? If they are worn, they may be worn to the point of failure?

If it were just the clutch slipping, I could figure something has gotten on its parts and might wear off. A sticking clutch plate, not engaging, really does point to either the cable, the lever, or the splines being dry or worn or all. St.
 
Grabby

I would plan on replacing the clutch disc, I had the same problem on a low mileage /5 with the original clutch and tried everything including lubing the splines, new cable, cleaning and adjusting every part involved. The only time it ever felt close to normal was when all parts were very hot due to weather and traffic. I finally replaced the disc only and it's so much nicer to ride, apparently the disc drys out and hardens over time and no amount cleaning and lubing will help. The job isn't to bad to do once you resolve to tackling it. Mike
 
If you haven't replaced your clutch cable, why not start there? It's cheap and easy. I recently replaced both the clutch and front brake cable on my '71 R75/5 and the improvement is huge. The abruptness in the clutch is gone and the front brake is smoother and more powerful. That would be a good time to clean and grease the cable and lever pivot points as well. In addition, I concur with the others that those input splines should be lubed soon if that hasn't been done.
 
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