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Bike Won't Start!

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I recently bought a 1984 yz250L and replaced the piston, split the case, took everything apart and cleaned it and I just put it all back together and it won't start. It hardly makes any sound except when I crank the throttle and even then it just makes a little more. The spark plug is firing and I just took apart the carb again and thoroughly cleaned it and checked the float height and crap and it was all good. I am not sure where to go from here. I am fairly new to mechanical stuff but I had some help with the splitting of the case and that, so any help would be appreciated. Thanks.

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seeing as how it is an old bike i would get multimeter and see what kind of readings you get from the stator up through to the coil and cap. You might be seeing a spark but its not strong enough.

Are you using a new plug? Which one? Is it wet when you take it out?

New fuel? What is it mixed at?

How do the reeds look? If chipped then replace.

Clogged air filter?

Is the idle adjusted properly or is the slide all the way closed thus not letting any fuel into the bike?

Are you getting good compression after the rebuild?

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It is a new plug and it was the same type as the last one which did work. The spark looked good. It didn't feel to wet.

Yes, it is new fuel mixed at 1:20 with racing oil.

Reed looked great.

I am not sure about the idle, I know I may very well be sounding like an idiot but I want to make sure; when the manual says one turn of the idle screw is it one revolution or like one turn of your wrist (one half revolution?)

Just cleaned and re-oiled the air filter.

I don't know about the compression, I don't have a meter.

One more thing. When trying to start it, I will crank the throttle and after a few kicks, the carb will start draining a decent amount of gas, is this normal, or is that a sign that the carb really isn't giving any gas to the engine? Thanks.

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One more thing. When trying to start it, I will crank the throttle and after a few kicks, the carb will start draining a decent amount of gas, is this normal, or is that a sign that the carb really isn't giving any gas to the engine? Thanks.

This is not normal. It sounds like the float height in the carb is set wrong. That is a pretty easy thing to check and adjust.

Did the bike run when you got it? Have you made certain that the timing marks are lined up?

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The float height looked good.

And the bike was in a billion pieces when i got it, the previous owner's nephew had put unoiled gas in it and melted the piston. But he said it ran great before that.

I don't know about the timing marks. How do i check it?

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