Backfireing

[liljosht]

is Backfiring bad for the engine?:confused:

[Silverfox@C&DRacing]

When is it backfiring?
is it when you let off the throttle or at a different time?

[hondafox440]

Backfiring is a condition of lean jetting, so yes it is bad.

[liljosht]

the engine backfires when i let off the gas

[hondafox440]

Sounds like your main is too lean. Richen it a size or 2 and see if it still backfires.

[liljosht]

what would happen to the engine if i do not rejet the main.

[sparks400]

richin up ur carb

[hondafox440]

You can sieze the engine if you continue to run it lean.

[liljosht]

I want to know if i keep the jets the same and let it keep backfireing will it ruin the engine. i like the way it sounds.I have the airbox lid on a K&N air filter and a FMF megamaxx2 muffler system.Ithink that is all the mods that have been done to the engine. i bought it used and he said nothing about anything else

[RuffRyder]

Well if you continue to run it lean.. It will damage you motor, period. WHen he got the K&N and Pipe, did he ever rejet?? If not then you really need to. If it backfires a lot everytime you let off, thens it too lean. Richen the Main like everyone said. Go up 2 sizes and test it. Also right now take out your plug. Is it white or brown?

[liljosht]

my atv is a 300 ex. a four stroke.it is getting enough lubrcation.

[hondafox440]

You aren't going to sieze it from lack of lubrication - you're going to seize it from lack of cooling. When fuel enters the cylinder and gets compressed, it atomizes on the piston surface. When this occurs, it is almost like when you sweat, thus is cools the piston off. If you are running to lean, this doesn't happen, and the top of the piston will overheat and expand too much, thus siezing the engine.

In laymans terms - Richen your jetting or you WILL blow your engine.