HI. I just put an HMF slip on on my 450r and was wondering if would need to rejet the carburetor. Thanks everyone

 

yes

 

See the HMF page here - shows what you need to do:

HMF Jetting Info

It Says

All pipes with jetting require setting the air fuel mixture screw 2.5 turns out from dead bottom. This will eliminate off throttle popping. If popping persists back off to as much as 3.5 turns out.

450R: 125/135 jets with the air box lid on. 180 with the lid off.

 

does that say from 125 to 180?

 

I can't seem to make sense of it myself - I put their pipe on my 2004 Rancher AT - and there is no jetting info on their site at all for it and they don't respond to emails to their tech email address and have not responded to the question on their own forum. I love the pipe though - it is awesome without a doubt.