i just got a yfz 450r, and i want a really good slip on for it. if u want let me know what u have on yours along with your jettings.

thanks

 

I don't have the R model, but the motors are very similar. I love HMF, and the new system they have out is sweet. I THINK HMF makes the current GYTR slip on, which is also a good unit. Dr. D is a good system as well, they have a factory Yamaha rider helping with R and D. There are a few newer systems a lot of forum guys swear by, but of the ones I have experience with HMF is the way to go.

 

I run a LEXX slip on and fuel controller works great!!

 

Always here good things about HMF. No jetting on EFI. Just fuel mapper of some sort as stated above. Good luck!