when i take the air box lid off my raptor it wont run right. Is that because of that hose that plugs into the snorkel, if so what do i do about it? plug it?


full yoshi
k&n pro flow
160/165 mains

 

It more than likely is because your bike is jetted just right for having the lid on.... Taking it off decreases the resistance to air flow, meaning more air which in turn means less fuel which spells "Lean".

I know nothing about Raptors, but if the hose is what I think it is, it comes from the motor.. it is a breather hose that allows backpressure - any pressure in the crankcase to vent to the airbox.. plugging it will cause pressure in your motor and potentially blow seals.... DO NOT PLUG IT.

 

newtz- 95 wolverine is right. when you took off the lid, it increased your air flow. so you are running lean. the hose that connects to the lid is the crank case breather. K&N makes a small filter with hose clamp that can be put right on to this tube

 

here is the link. www.knfilters.com/vent.htm

 

thanx guys, but if i wanna run the lid off what size jets should i use cuz im already running fatter than yoshi recommended