Dirt bike thats hard to start..

Not sure of the age of your YZ 250 ( You never said!) but in most Yamaha they use dual stage stator which means a stator will charge a spark plug at two speeds one on kick starter speed and the other on running speeds it is common that the low speed circuit on the stator to fail leaving you with a bike that only starts when pushed its a very simple test to diagnose it be worth checking you have spark on kick starter speeds with spark plug out the motor but still connected

may have bad fuel.... has bike or fuel been sitting for a long time. drain tank and the carb bowls. try New Fresh fuel ... What do you mean by taking water??

One, That thing should fire up in a second, if not, you got to get it so it will. Try not touching the gas, just pull on the choke, and give it a try. If that doesn't do it, try something else next time. I had a KLR 250, kick only, and that thing would start first kick every time, no matter what. I loved that little bike. Hope this helps.

if the bike push starts, i assume it runs good,
if the kick does not turn motor over, there is a spring clip that engages the kick gear that may be broken or misplaced
if the kick start turns the motor over, you have to use decomp to get just past TDC then kick

I see: you changed the plug because it was backfiring.

Does it back fire when you let OFF the throttle after revving it, or does it back fire while being revved?

If it does it when you let off then Ollie's suggeston might do it. If that doesn't do it then check for dirt in your pilot jet.

If it back fires when revved up high could be dirt in your main jet.

That lever is a compression release and pulling it will make kick stating an excersie routine. Kick start without the pulling the lever. See how that works. good luck.

I assume this is kick start only, and by now your right leg is twice the size of your left one ! correct?If you can't find a long nearby hill, get a trusted buddy to pull your bike w/ another bike or car/truck. Attch rope to bottom triple clamp and don't go over 20 mph, use 2nd gear...this may sound risky but i have done it many times and find that nothing clears out an engine faster !...Good Luck to you friend...Tim

i used to own a yz426f and it had the exact problem... a fresh plug will fix your problem. change the plug and the bike will run great. also don't start the bike and shut it off , my bike would be fine if i started it and rode for a while getting to the proper heat range help save the plug. if my bike didn't start in one or two kicks it was usually the plug.



hope this helps