2-Stroke with hot starting problem

[Robabob]

Hi, I fairly recently bought an RM250 which when using it for my first Enduro I found it doesn't like to start when hot.

When I first got the bike it wasn't great at starting cold either but after a carb clean and fresh fuel that problem was solved. Since discovering the hot start problem the only thing I've done so far is change the spark plug which seems to have helped a little.

What things would you recommend checking first? Anyone else had the same problem with an RM?

Failing suggestions on how to fix the problem any exercise recommendations for the gym to build good kick starting muscles?

[KcDavis]

How is the top end? Maybe run a compression test. Usually 2t's are even easier to start hot than when they are cold.

Perhaps fuel flow is stopping somewhere in the line. Check the cap breather tube. Check the reeds, they can cause all different kinds of problems. Have you checked for spark when it's hot and not starting?

[rusky]

Check for air leaks, change plug, test coil, check reeds for cracks/chips.

[pittss1c]

My rm250 hot starts with the throttle wide open from the first kick. Doing that means that it starts on the first kick 98% of the time, but every bike seems to be different.

[Robabob]

Cheers for the suggestions. I'm going to work on the bike this weekend and check all these things.

What should the compression reading be for a bore in good condition?

[pittss1c]

Not sure. I imagine it depends a bit on your year. I have a 97, and a fresh topend has 185-190 PSI. I would think things would start going south near 130. (I have an old RM that is totally and completely worn out and it still shows 100 PSI)

[Robabob]

Not sure. I imagine it depends a bit on your year. I have a 97, and a fresh topend has 185-190 PSI. I would think things would start going south near 130. (I have an old RM that is totally and completely worn out and it still shows 100 PSI)

Cool, mine is a 98 so I guess it'll be similar to yours