2003 RM 250 - no bottom end and fouls plugs

Im desperate for some guidance. I rebuilt my carb this winter with a stock rebuild kit hoping to remedy the bottom end issue. Now it still runs like crap at low RPM's and fouls plugs. I run Castor oil 44:1The bike has a pro-circuit pipe and shorty. Im ready to take it to the shop but if there is any thing else I could try please share your ideas. Thanks in advance.


Does it clear up and run ok at higher rpms?

Sounds like it needs to re jetted.

Sounds like you need to do a leak down test: you will probably find it needs crank seals.

Once a motor has been jetted, it should never need to be re-jetted, accept for mods or air pressure changes.

So chasing a jetting problem is a waste of time.

thanks guys...its in the shop to be re-jetted.

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