Clutch issues

[Richard Toghill]

Hi, the clutch on my 74 250 HS is extremely heavy and does not disengage fully. The cable is new, there is no excessive wear to the  clutch drum or basket. Clutch springs are 1.7mm so could be from a 400. Is there a trick to getting the clutch to operate in a useable way?

[Carl Hill]

Assuming your clutch spring preload is even and correct (this is critical) , you may want to pull the clutch throw-out apart and go through it. These seem to have been a high wear item. If the bearing cover is worn out you may have to replace it rather than rebuild. There is a small pin inside that pushes against the clutch rod. I replaced mine recently and was amazed at how much better the clutch worked. Al B. At Penton parts USA should have everything you need.

[Larry Perkins]

Also make sure your clutch rod or rods depending on which mechanism you have roll straight on glass.  Any little bit off and it is a bear to pull.

Larry P

[Richard Toghill]

Thanks for tbe info. I currently have a left arm like Popeye!

[Paul Danik]

Hi Richard,

   If you go to the upper right corner of this page there is a SEARCH feature. If you click on it, then enter KTM CLUTCH in the search for box, then click MATCH EXACT PHRASE then hit search, you will access lots of great knowledge on your question provided by the fine folks on this website. Not all of it will pertain to your exact situation, but much of it does.

Hope this helps.
Paul

[JP Morgen]

Most of the pressure of the clutch springs has to be held by the very first plate that is installed into the clutch basket. I have seen the KTM engines with different 'first' clutch plates. If the first plate is not strong enough to resist the forces, it flexes/bows inward, which means more travel is necessary to disengage the clutch as compared to a clutch with  stiffer/thicker first plate. Hope that helps.

[Mike OReilly]

I tackled this on my MC5 late last year and cannot believe what it is possible to achieve. The clutch pull now feels like a Jap bike.

The two key areas that I focused on were:
Getting the clutch push rod length correct (which required replacing the two push rods and the ball available from Al B.);
Also pulling apart and cleaning the throw-out assembly. In all my years of owning Pentons I had never done this, and it is not difficult. I think it is a critical part of the process.
From what I could see in his Al's catalogue, the throw-out is no longer available.
I would suggest focusing on the above and only of the problem still persists, worry about the guts of the clutch.

Hope this helps,
Mike

[skiracer]

Hey Mike, what measurement did you use for the "correct" push rod length? I too have an MC-5....

quote:Originally posted by Mike OReilly

I tackled this on my MC5 late last year and cannot believe what it is possible to achieve. The clutch pull now feels like a Jap bike.

The two key areas that I focused on were:
Getting the clutch push rod length correct (which required replacing the two push rods and the ball available from Al B.);
Also pulling apart and cleaning the throw-out assembly. In all my years of owning Pentons I had never done this, and it is not difficult. I think it is a critical part of the process.
From what I could see in his Al's catalogue, the throw-out is no longer available.
I would suggest focusing on the above and only of the problem still persists, worry about the guts of the clutch.

Hope this helps,
Mike

1976 MC 5 Original Owner
1976 Penton 175 XC
1985 20' Hi Point trailer

[Mike OReilly]

As per Al Buehner's parts catolog (which is where I got mine), correct length for each of the two pushrods is 108 mm.

Having the correct length then gives you the proper measurement for the clutch release lever in front of the countershaft: 42.5 - 43.5 mm. from the lever to the face of the bracket itself (as illustrated in all the manuals).

If the measurement above, for the lever is off, it is a sign that the pushrods are worn and need to be checked.

To my original point: if you have a heavy clutch, check the above first and make sure that is all in order, prior to digging into the guts of the clutch itself.

Mike