i just bought a 98 trail blazer 250. on sunday i road it with some friends on the trails it ran great but it needed a front sprocket and battery so i pull started it all day until the rope broke, wed. night i put on a rear & front sprocket and on thu. morning i put on a new chain and battery. thu. morning the quad fired right up with the button. thu after work it fired right up again. on fri after work i was suppose to meet with the guys and ride, i fired the bike up when i got home to warm it up, got to the ride site and it will not fire up. the bike cranks with the button, has a new plug with the correct gap-is getting spark,getting gas & oil but still won't fire. i don't understand why it fired up and tem min. later will not. has this happened to anyone? and how do i fix it? thank you for your help!!

 

check the air filter

 

if the filter and duct working was not on when trying to start the bike would that cause it to not start? because we had it out to spray starting fluid in to see if we were gatting gas and it still would not fire.

 

no it should have fired. you should stop spraying starting fluid in there that is 2 stroke death..
how does your plug look?

 

did you flood it is the plug wet?

 

the plug is new and gap is correct. i think the problem is in the rings, only 75 psi on combustion not the inked 125 in a service manual.