when i start my raptor, when the engine is cold it lets out a big backfire and when it does i let go of the starter button and wait just a second push it agine and it fires rite up but it only does after it has been sitting over-night a gotten cold and it only does it the firest time i push the button

i was thinking valves or decompresion release but before i start into it i though i would see if you guys had any idea

 

I don't think it has anything to do with your decompression release or your valves. Sounds to me that you might be running a little rich and when your starting it up after it's sat for awhile your blowing out unburnt fuel. JMO

 

i don`t know what it is it did not do it today i don`t know you might be rite on the ritch allthough everything is still stock it has been pretty hot here latley and air filters probably dirty, to go with hot it has dusty here.

thanks man i`ll check filter and plug