need help quick please

[mxracer32]

i have a 1999 yzf400 and i just reset the time and its right i think cause it will run but when it start it backfires alot but it wont do it if u leave the choke on and also when u turn the choke off and keep it at a high idle it will run then when u let off it will die like it has ran out of gas. any thing will help thanks

[Fastest1]

When you say you "just reset the time" what do you mean? Cam timing or ignition timing? I actually suspect a dirty carb, but I would really like some answers. When was the last time it was running? What happened that made you change something? Fresh gas? plug?

[mxracer32]

it was the cam timing and i reset it cause i put new rings in it and piston and i got a new plug and fresh gas in it to. but i dont get y it dont do it when i keep the choke it runs fine. its been about 2 months since it was ran.

[Fastest1]

Are you saying it only runs with the choke on? or off?

[gfergtr74]

Check and clean the carb. The problem is probably there.

[mxracer32]

when i go to start it i turn the choke on and it starts and then it will run just fine then when i go to turn the choke off it will start to backfire and want to die out.

[yamaha.dude]

The old "upside-down-slide-in-the-carb" trick?

David

[sirthumpalot]

YOu said it has been 2 months since it was run. Did it run OK before the 2-month wait? If yes, then clean the carb. If you are not sure or you did not run it before putting it away for storage then check the carb slide as suggested above, re-check the cam timing and valve clearances, clean the carb and let us know the result.