worn out

[newgasser34]

What is it that wears out on a 2 stroke that makes the engine run super rich? I just bought a 2003 ec 250, I have been playing with jetting and can only get the bike to run on a 160 main jet, and have put in every pilot jet from 45 to 35 and it will not idle. I have a 38 in it now but it is running on the jet needle. the pilot port is not plugged up ive checked it several times. also the left side PV cover seems to be preasurized pretty high is this normal? do I need to look at the engine or carb

[stay_upright]

A couple of things to check are the float height and wear on the needle.

In non-racing carbs you can replace the emulsion tube which wears quite a lot but you can't on the Keihins leaving you with the option to jet around it....

[Skidad]

Worn reeds, leaking clutch side crank seal, over oiled air filter, dirty or clogged silencer, stuck power valves, wrong heat range plug, weak ignition spark, worn rings/piston, worn needle bore, choke assy. not sealing properly, other clogged parts of the carb, float height or worn float needle.

That should be enough to keep you busy