Rebuilt carb on '04 RMZ-250 and it won't start

I bought a pretty clean 04. It ran but wouldn't idle when I bought it. I pulled off the carb and cleaned it out-- it was pretty clean.

Now, it won't start.. I screwed around with the idle speed djustment screw and wonder if that is my problem? I attempted to adjust the idle UP, hoping to just get it running.

I also re-adjusted the idle-air (2 1/4 turns). The previous owner put an aftermaket adjuster screw in.

Any suggestions?? I have read all of the comments about valve adjustment and plan to do that. But I want to get it at least running again first.

BTW- I've been kicking it over as suggested here(in neutral). I've also tried pop starting it in 2nd


usually if your idle speed is set to high it becomes very difficult to kickstart the engine, you say your fuelscrew setting is set at 2 1/4 turns out from full in? also what pilot jet do you currenlty have installed? if i were you i'd check the spark plug condition and see if its dry since it can tell you if your engine is receiving at least some fuel

Carb jets all appeared to be per the book, except the main was a 175. New spark plug, and the bike is getting spark and fuel. I've re-confirmed that the fuel screw is at 2 1/4 turns.

I noticed that the hot start plunger, wher it screws into the carb was a little goofy. The boot appeared to be poped off of the part that screws into the carb. I fixed and also adjusted the cable so that I was sure the plunger is all the way in.

I adjusted the idle setting so that the screw just touched the throttle cam, then I gave it about 1 more full turn, so that it holds the throttle only a little open. *** is this correct??? ****

NOW: If i kick it using the recommended technique, I can get it to fire and run for 5 seconds, then it will die. I found that a quick twist of the throttle while kicking will get it to bump over.

Thing is - I don't know if its carb or valves.. am I wasting my time messing with the carb and should I jump righ into the valve clearance check?



Check the slide, the flat plate on the slide can easily be installed upside down and it will keep the bike from starting.

The slide looks fine, and I double checked it with the manuals.

My valves are WAY out: both intakes at 0, one exhaust at 0.024 the other at 0.014.

Are these kind of numbers normal ?? Those exhaust numbers seem crazy loose.

the intakes are supposed be between .004"-.006" and the exhaust betwen .007" and .009".

Good luck with that bike I had one an it was easily the worst bike I ever owned. After I solved the overheating problem and the valve problem the transmission came apart. Made we want to get out of riding and buy a boat it would've been cheaper\

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