Ok well first I never have and never plan on riding a motox bike. I plan on buying a 07 KX450F and then completely stripping it down to frame/swingarm/motor/trans and selling off the rest of the parts. Im converting the bike into a 450cc road racer for the track. check out 450moto.com

NEWAY!! I currently ride a 07 Kawi 10r and have never ridden nething but a kawi and wanna keep it that way....but i have come between the yamaha yz450f and the kx450f. My question for you guys is...how reliable is the kx motor and trans? How many hours have you guys gotten out of your 07 450's before rebuilding them? Are the trans pretty good on these?

Thanks for your help! Hoping the responses are what im looking for, would be a shame to have a Yamaha sitting next to my kawi green 10r!

Buddy of mine owns a kawi shop and turned the 07 KXF450 into a road racer. He had the suspension modified to drop it several inches on either end, put the motard wheels on, a set of narrow t-handle bars, a custom air shield. Geared it to something like 15/30 something and went out and kicked A$$ for the season.

At the end of the season the valves had not moved at all (still in spec.).

He said he could go around people on the outside!!! of the corners and would laugh every time he did.

Personally I have a season and half on the 06 with no valve movement, a season on the 07 with no valve movement, and now flogging the 08.

Motor is strong on all three bikes.

Thats exactly what i was lookin for! Thanks. Looks like ill be adding another kawi to my garage. I have to use certain "conversion kits" being made to enter in the new 450cc racing class, its gonna be a great and affordable class to be competitive in! I don't want an 06 at all since it only has a 4 speed, rather have the 5 speed.