Need to know if anyone is running a GYFR(factory yamaha perf pipe) On there YFZ450. If you are i need to know what your jetting is. I guess someone that is closer to sealevel. Or even if theres a place i can see what jetting i need to be running. Any info would be great thanks!

 

What else you got done to it??
Airbox lid still on, or removed??
Cam mod done????
Aftermarket airfilter??

Here is my set-up, hopefully it will give you a ballpark idea.

Stock motor
DR D pipe
Airbox lid removed
Stock airfilter (for now)
172 main (stock 158)
stock needle 5th clip (stock 4th clip)
45 pilot (stock 42)
Fuel screw 2 1/2 turns out

I am also at sea level.
If you are set up similar to mine, maybe this will give you at least a starting reference.
Hope this helps.

 

My set-up for my 2 yfz's are in my signature.......My main jet size is different than 2funs, maybe cause he's running no lid air box & i'm running EHS lids on mine.......I am at sea level.....