i was riding my raptor and stopped for a while, when i started it up all i heard was a big backfire like an explosion. i tried to start it for another 5 sec and realized something was wrong. i searched the bike over and found my carb boots where the carb goes into those tubest that connect to the engine had blown off. all i had to do was loosne the clamps and reinsert the carbs into the boots, but it scared me. a friend had a i think polyeurethain set of carb boots. they never poped off on him. did this happen to anyone else?

 

Yes on a backfire I've blown off the boots a couple of times. Once you get the hang of it you can get em back on without much trouble so it don't bother me much.

 

If its backfiring, something's wrong.

1) Check your jetting. A lean condition can cause backfiring.

2) Check your valves. The most common cause of backfiring in liquid cooled engines is the tendency for the valves to lose clearance gap. When this occurs, the valves may be partially open during the power stroke allowing combustion to backflow through the intakes and overpressure the boot between the head and the carbs.

Yours may have been an isolated incident, but wouldn't you feel better if you made for sure?

Also, some people may try to tell you that aftermarket carb boots are the solution here. However, a backfiring engine is a sure sign of a problem. Though new boots might keep you from having to take down time on the trail, its only a cover up for the real problem and said problem will only get worse if you don't find the source.

~HoundDog

 

well, my quad backfires very softly and sputters when i downshift or let off the gas. whn i jetted it, the only thing i didnt do was adjust my air-fuel screws. if it is running rich, can i just remove the air-box lid as an easy fix?

 

Try turn your idle up this was a problem when they 1st come out. You may be too lean also