Okay I have a 05 450r... Full Exhaust, No Lid, K&N, Rev Box, HRC Cam.... I am currently running 180 main and stock pilot... I am confident there is more power out there and the jetting is the problem... What do you all reccomend for main jet, pilot jet ,needle , and most importantly where to I set the mixture screw...

My spark plug is currently a light brown color so I think I am running lean, and maybe too lean... My bike seems to level out at high RPM and it seems it doesnt have enough fuel...

I currently own two 05 450r' s mine is described as above, the other is basically stock other than no exhaust end cap and a K&N filter. This bike can hang all day long with me on my modded bike, I am about 205lbs my buddy I ride with is only 155 so I think this has something to do with it however I still think theres more power waiting to be unleashed. We are both of equal skill level as we have been riding tgthr for years and always the same bike. Let me know what you think about the jetting any help is better than where I am not... Thanks

 

I would say to go to a 50 pilot, but that shouldn't change top end. It could help get it there better, though. I ran a 185 in my carb when it was still unported. I would say go and get a 50 pilot and a 185, then try it again. I have gone from 2.5 to 3 turns and never really noticed a difference.

50 pounds is alot. It is said that 7 pounds lost is a HP gained. You are 7 hp behind, if that theory is true.

 

Zettler I would get rid of the k&n forst before you go ruining your engine just a little heads up.

 

Funny you say that about the filter... I just bought a UNI Foam filter Wens, I dont feel right going to the dunes and sucking in a bunch of sand in to my engine... I am going to play with the jets tmrw and make a few runs in the fields behind my house see what changes I get hopefully it picks up a little speed.... I am going to the dunes with my other 450r and my buddy Chris who has a modded YFZ450 hes about 130lbs... Last time we went he walked all over me, I guess with the weight to hp theory I am 10HP behind... I thinks its time for a 520 kit.

 

Well thats good to hear I got a K&n for xmas and I returned it, it was a nice gift, but not nice enough, I don't want to be ruining my new engine.

 

I have a UNI filter, Athena 480 kit, ported and polished head, Hotcams Stage II, FMF Q2 slip on and I am jetted at a 185 main, 50 pilot and dropped the clip on the needle to the bottom.
I probably need to go a turn out on the air/fuel screw since it pops a little on decel. Otherwise it seems spot on!