I have notice that my M20 1940 works fine until he warms up (air temperature around 30 - 35 degrees). When the engine is hot its hard to shift down. I have a SAE 40 oil in my gearbox.

Also I have notice that till the engine temperature is not so hot the clutch is doing well but when its hot I have the filing the clutch does not work good because when I am standing still and give it into 1st gear - press the clutch leveler (to the end) the motorcycle seems to go forward regardless the fact that I am holding the leveler presed.

These symptoms showing only when the engine is realy hot (if I drive more then 15 min on a hot day).

Thansk for the answers.

BR, Mitja

email (option): mitja.peterka@siol.net

All of your symptoms are classic dragging clutch problems and this is often exacerbated by heat. It causes the plates to swell and expand and internal clearance is lost.

You need to make sure that you are not losing any lift at all - check endfloat etc. If your clutch is slipping under load when cold it will soon overheat and then drag.

Alternative linings might help.

You should be able to 'paddle' the bike backwards in gear with the clutch lifted - if not then it is dragging excessively and it is a vicious circle that will only generate more heat.

All the above plus check the plates are lifting evenly.

Also check that the clutch operating arm on the gearbox is set correctly...Ian

email (option): ian@wright52.plus.com

And check if your clutch push rod is the right length (not to short), making good adjustment possible.

How long is the correct clutch push rod?

BR, Mitja

email (option): mitja.peterka@siol.net

I found it on the net it is 32,38 mm or 12"3/4.

But there is also a part in the catalog with the part number 65-3162 "Operating arm pivot pin" what size is he because I think I dont have one instaled in my push rod.

What size is the part S9-3 Push rod ball bearing?

Br, Mitja

email (option): mitja.peterka@siol.net

You must have the pivot pin or your operating arm on the gearbox would not work. It's the pin that is the hinge for the arm. From memory the ball is 1/4". Ron

email (option): ronpier@talk21.com

The clutch pushrod ball is 5/16 diameter...Ian

email (option): ian@wright52.plus.com

That is 8 mm am I correct Ian?

email (option): mitja.peterka@siol.net

8mm is about .0025" bigger than 5/16" but it should go in...

Note that on original arms the ball was fitted and then the front of the hole the ball fits into was swaged over slightly...
This reduced the holes diameter slightly at the edge to make the ball 'captive'...In other words to stop it falling out...

For that reason you might find the hole a little tight at its front edge when fitting a new ball but it should move freely once past this point...

If you want to swage the hole after fitting the ball use a larger ball bearing and a hammer to reduce the size...Ian

email (option): ian@wright52.plus.com

Thanks Ian and all the others for the informations :)

BR, Mitja

email (option): mitja.peterka@siol.net