My 02 yamaha raptor is starts up and idles but bogs,sputters and backfires when you give it gas.It was running okay but took a little time to warm up then it all of a sudden started bogging when you give it gas.It was running strong and fast.I have replaced the spark plug which looked okay and tested the wire and coil.It has a K&N filter but is otherwise stock.Do you think it is the carbs, ignition or valves? Thanks for your time.

 

parking brake.. check the parking brake.. then remove it

 

Thanks for the quick response, can you tell me the the things i should check on the parking brake that would cause this?The dealer said the carbs are dirty and need to be cleaned or the needle is clooged or something like that.I have a clymer's manual for it.

 

on the rear brake there is a "level" on the left side... press it forward.. see if that fixes it ..

 

Also do you think the cab intake "boots" could be loose.I have the plastic off and havent really checked this but i heard this could cause this from other forums.

 

try what i said first

 

Thanks, I'll check that out.I heard that could cause problems.Where exactly is the level on the machine?

 

lever.. it will look like a bicycle brake line going to it ...

 

Is it on or next to the foot brake? because i thought that was the rear brake.

 

it's on the rear brake caliper itself