I just bought the Yoshi comp full system and the K&N air filter. There spec's say 150/155 main jets. Is this what every body is running or will I need different jets than these? I do have a dynojet kit but it only goes up to a 150 main. My elevation is aroud 800 feet.

 

Use the 150/155 like Yoshi says if you put the holes in your airbox lid. Make sure they are genuine Mikuni jets. They also recommend 1.5 turns out on the airscrew. I had lean popping at this setting and ended up 3 turns out and it runs perfect. I think it is an emissions thing. Don't waste your $ on a jet kit. Good Luck. You will love it.

 

I ran the dynojet needles/jets....and I still do. If you have only the exhaust, and filter, and your elevation is ~1000ft..then run 148/150. This is what I ran..and it ran great. Do not mismatch Dynojet needles and mikuni jets or vice versa. Your bike will NOT run well at all. Also remember...Dynojet jets are larger than mikunis..which is why I ran a 148/150 on DJ's, and probably would have run 165/170 with mikunis. Compare the needles side by side and you will see why. Btw..I ran this setup with no airbox lid.