Last week I was driving my M20 for a short while on a main road, at a relatively "high speed" (wich I normally don't do)
Suddenly the bike sputtered and stopped altogether.
There was no compression anymore.
Two minutes later the compression was back and I could ride the bike back home.
What could cause this trouble, maybe an overheated exhaust valve ?
If so, what could be the reason for that ?
Or is it something else ?
It's not a matter of running in, as I have used the bike over a long time now. The valve clearence is OK too.
As you have checked the valve clearances, I would check that the decompressor is set up right and then check your head bolt torque settings, that the spark plug is seated OK and that the timing bolt is seated correctly.
You are probably best to take the head off and check the head gasket.
I would have thought your exhaust valve has nipped up in its guide, as soon as it cooled the spring pulled it shut. You may have to investigate this and see if it has any pick up marks. When you do look for weak mixture markings.
As well as the carb settings (main jet, needle setting and throttle cutaway) check that you don't have any air leaks and that the ignition timing is set correctly (sufficiently advanced)....Either of those conditions will lead to overheating if present...
Retarded timing settings will certainly cause you overheating problems at higher revs. and are a very common problem in my experience as a 'near enough is good enough' attitude seems to prevail in many cases...Ian
good question, but I have been busy, so haven't come to it yet.
First Í will check the ignition timing - it seems to change a bit over a long time (anyone else got that also ?)
Then the carburettor,
I will let you know in time.
Thanks for all the advice.
It seems Noam had the same problem on an previous engine. Problem not solved ?
