2002 rm250 2 stroke wont start!

So i bought a locked up rm250 and rebuilt the top end. It kicks over pretty damn hard but

Just wont start. Has spark and fuel is clean along with clean carb. I got pulled a mile behind a truck and it stil wont jump in any gear, it sputters but dies right away! Maybe needs

Honing so im getting that done this weekend ! Please help

Is the filter clean? Do you have anything in the airboot? One time my bike would not start after a rebuild and i went through just about everything before i remembered that i had stuffed a bag in the airboot before the rebuild! Good luck and hopefully it is a small fix.

reeds in good shape?

Yes i checked the reeds , not sure what they do but seem to be in good shape, no cracks or chips

Have you checked the exhaust system for blockages and that the ignition timing is correct?

Highly unlikely that honing will make any difference to this problem, and anyway it's something I avoid on these nikasil bores.

idle circuits not clean is what it sounds like. or your carb isn't set up right.

How do i clean the idle circuit or check timing on a two stroke?


well the idle circuit is what the pilot jet screws into, basically spray some brake clean in there and then blow it out with some compressed air. the timing on the rm he's talking about is the stator, under the stator cover theres a rotor and you can see the stator mounting bracket behind the flywheel, if you look close on the bottom screw slot of the bracket there should be some line up marks on the bracket and the cases if they're lined up thats not your problem, but if they aren't loosen up the three pan head screws and align the two marks, tighten and re assemble.

Carb is all clean, im gonna look into timing

Have you tried an aerosol starting aid, if it starts then you know you've got a fuel

Issue I doubt it would be a timing issue it would have to be a fair way out for it not to run

did ya put the piston in backwards?

I tried starter fluid and wont start still and im thinking the piston might be backwards but it is pointing the right way, the arow is atleadt

It still doesnt start with starter fluid, piston is pointing toward exhaudt side

and you're sure you're getting spark? have compression?

Yah im getting compression and spark

Could be something in the bottom end. Old peice of piston or something. Could you of left or dropped something in the crank. Could be a possibility why its so hard to kick.

Also what's the plug look like after you've been trying to start it? Is it wet? have you tried a new plug too?

or if it was locked up then the bigend of the rod could be locked up too, rolled a needle bearing or whatever.

I just gave up on the bike and took it to a good bike shop to see what it needs ,

Hope to get it done soon and for cheap

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