Clutch "grabbing" "snatching"

[quixotic]

I'm quoting from the Haynes manual, but it sounds like what I'm experiencing, where a small amount of clutch lever movement translates into a sudden grab down below.

Would this be fixed with a spline lube?  Or a check of the thrust components?  Or the axial play of the input shaft?  (I hope not the last one).  

Or is it just the nature of the beast?  Just seems strange, since the clutch movement on every other bike I've owned has been nice and gradual.

[Bob_Roller]

First things I would check, is the clutch cable at the handle bar, they have been known to fray at this end, had it happen once .

Next would be clutch cable adjustment, you want a little bit of freeplay at the arm at the backside of the transmission before it contacts the pushrod that moves te clutch plate .

You also need about 2-3 mm freeplay at the clutch lever befor the cable is moved .

[Luca]

+1 on checking that the clutch is properly adjusted.  Proper adjustment will give you the best mechanical advantage at the lever, which in turn will give you the smoothest operation.  The clutch adjustment seems odd at first because you use the bottom to adjust the top and the top to adjust the bottom.

Snowbum has a good article on the procedure.  You set the clutch arm end the proper distance (I cut a chopstick to the right length and used that as a gauge--talk about Chinese tools!) from the little tab on the transmission casting that holds the clutch cable by adjusting the cable at the lever.  Once that is set, you adjust the free play at the handlebar lever by adjusting the screw on the clutch arm.

Given that you were unhappy with the dealership that sold you your bike, I would plan to lube the splines anyways.  I kinda doubt that they did.  At the same time you can clean and lightly lube the throwout bearing and also clean and lube the clutch arm bearing.

The first time I lubed the splines I didn't remove the clutch arm or the throwout.  I noticed a much smoother operation once I cleaned and lubed that stuff.

Only special tool you will need is a necked down 27mm (or 1-1/16") socket for the swingarm lock nuts

[quixotic]

Given that you were unhappy with the dealership that sold you your bike, I would plan to lube the splines anyways.

Yup, that's first on my winter to-do list.  I remember doing it on my old slash 5 about 10 years ago, but do you think I can find the socket that I took forever to file down?  

[quixotic]

Next would be clutch cable adjustment, you want a little bit of freeplay at the arm at the backside of the transmission before it contacts the pushrod that moves te clutch plate  

Thanks.  I'll check that.  All I did previously was make sure that it was parallel to the back of gearbox.  

[georgesgiralt]

Quixotic,
Instead of grinding a hardened socket, try the improved method to get the gearbox out without removing the swing arm.
The trick is to remove the 4 bolts on the transmission side of the gearbox, put a jack under the engine, unbolt the mufflers at the coupling tubes, then remove the engine's bolts and pull it forward as far as it will go. You gain enough place to remove the gearbox and, depending on the job at hand you do not have to remove the carbs (but the airbox...)
The bike stays on it's wheels and so is stable...
It is described in the post 1983 version of the maintenance manual, and I must admit that it makes the gearbox job much easier !

[Barry]

Or is it just the nature of the beast?Just seems strange, since the clutch movement on every other bike I've owned has been nice and gradual.  

It is the nature of the beast to some extent in that it's possible every other bike you had used a multi-plate oil bath clutch and this is a single plate dry clutch.

It may get better on it's own for two reasons:-

A dry plate clutch that has be stood a long time without use will have some surface corrosion and that will wear off in time  and make it less grabby.

Other reason is you'll get used to it.


Spline lube may improve the gear change and you may want to do that in due course. In the absence of a lathe you can do a very passable job of grinding down the socket using an electric drill and an angle grinder. Fix the drill somehow and mount the socket in the chuck using a large nut and bolt. With the socket rotating you can apply the angle grinder and produce a very neat finish. If I posted a picture of mine you'd be hard put to tell it wasn't done on a lathe. And I have access to a lathe at work but couldn't be bothered waiting until after the weekend.  Remember to grind the lead in off the face of the socket as well.

[steve hawkins]

I find adjusting the bite point of the clutch to be critical to being happy with its operation, every one has different size hands, and your finger's reach will be different to mine.  But, as alluded to above, the bite point must be where you have the greatest fine control when you are letting the clutch out or pulling it in.

Cheers

Steve Hawkins

[Luca]

All I did previously was make sure that it was parallel to the back of gearbox.

The clutch arm should not be parallel to the gearbox housing.  It should sit back at a slight angle, da Bum says about 4 degrees.  When the handlebar clutch lever is halfway through its travel, the clutch arm should then be parallel to the transmission.

Having the clutch arm parallel to the transmission will give you the best mechanical advantage.  You want the clutch arm to move through the point of best advantage while it is in the middle of its travel.

And as Bob said, make sure you cable isn't fraying at the handlebar.  If it is, it will break soon.

[georgesgiralt]

I, for one, would first set the clutch play by the book.
Then run the bike to see if the clutch behave correctly or not.

[Barry]

As Luca said the clutch operating arm should be parallel to the gearbox when the handlebar lever is at half travel. Thats what the book setting method is aiming to achieve and should give the best control.

I've got to say I'm skeptical about how hyper critical the adjustment is within reasonable parameters. It's aiming for best mechanical advantage that's all. It's going to feel different after adjustment but I suspect we get comfortable with a particular setting and then don't give it a 2nd thought.
  

[Luca]

Right, the only functional concerns are that you

1) get full clutch disengagement
2) don't ride the throwout bearing