My 2001 Rev 3 250:

Started ok ran for about 20min, i dropped it on the left hand side on a steep loose slope, it cut out, i restarted, then it will ran for 2 mins and cut out, then it could not be restarted for about 2 mins, then it starts fine runs for two mins, then it cuts out, leave it for 2 mins then it starts Ok, and so on and so on...

I striped the carb and that is fine, i tested the spark and that seems to be the cause of the cut out, but what would make the spark stop for two mins, then come back - run ok for 2 mins then go away again etc etc?? I am stumped.

Any suggestions where i should start to look for the problem?

sounds like a stator issue to me.

I would have a look at the kill switch. Disconnect it and try again.

Have you timed it?

I'm not being pedantic here but if the intervals are approximately consistant it will help diagnose.

If the times are consistant then I would suspect the stator. As the bike heats up the stator would expand resulting in an open circuit. When cool the stator will work.

Peter, I doubt it's the kill switch. This would be binary and either work or not work. I suspect that dropping the bike on the LHS was coincidence. However is an easy check and it will do no harm.

Edited December 1, 201114 yr by TooFastTim

Have you timed it?

I'm not being pedantic here but if the intervals are approximately consistant it will help diagnose.

If the times are consistant then I would suspect the stator. As the bike heats up the stator would expand resulting in an open circuit. When cool the stator will work.

Peter, I doubt it's the kill switch. This would be binary and either work or not work. I suspect that dropping the bike on the LHS was coincidence. However is an easy check and it will do no harm.

yes the cut out and run times were quite consistently between 2 and 4 mins, if it was stopped longer it would run a little longer, thats a clever point- that it might be something to do with an eletrical component cooling off and heating up and cutting out, but then how would a light drop on the left damage the stator?

but then how would a light drop on the left damage the stator?

It didn't. It was just a coincidence.

Actually I revise that. What can happen is that the stator when warm or hot is more malleable is more likely to get damaged.

Edited December 1, 201114 yr by TooFastTim

I'd check the fuel system [including all feed pipes, unions, the breather hole in the tank cap and completely strip and clean the carb]as that sounds like there's not enough fuel getting through [the bike equivalent of intermittent claudication....]

Best wishes

Will-in-the-mud

I'd check the fuel system [including all feed pipes, unions, the breather hole in the tank cap and completely strip and clean the carb]as that sounds like there's not enough fuel getting through [the bike equivalent of intermittent claudication....]

Best wishes

Will-in-the-mud

Good point

Is it a sticky float in the carb? seem odd to be a stator if it was running fine before the crash? unless it was a big crash!

losen the fuel cap and run it to make sure its not creating a vacuum in the fuel tank?

Rich

I removed the carb and cleaned everything, i inverted the carb while on the fuel and that ran no prob, with the tank cap off. so no obvious problem there.

I took off the flywheel cover and undid the bolt, but with out a puller i could not release the flywheel to look at the stator, it was making a funny noise in there which i videoed rather than try to explain:

http://youtu.be/-TOodCmU1Uk

Could it be the coil? it did fall on that side... how can i test it?

sounds like it needs to come apart. I have seen leonelli flywheels come apart internally.

Golen rule with all these things is cheapest first, well in my book. A cracked plug can cause these symptoms as it happend to me once. So change this first - miracles can happen.

you need to find whats causing that noise first ,poss the magnets have come loose from the flywheel or something loose on the stator ,my freinds just had a prob same as you describe on his 2000 rev3 turned out to be the stator

I agree. Start simple and get clever later. A new plug never hurt anyone.

You need to use compressed air to clean the carb. Carb cleaner makes it shiny but won't shift a particle in a very small hole - not enough presure.

Idle/tick over circuit prime supect and not main jet etc.

I just cleared up a very similair problem today. Gas cap.