kmx125 converted to 200

[renzy1]

hi,ive changed the complete top end kmx125 to a 200 ie head,piston,powervalve ive also changed the exhaust for a complete big1 kmx200 and im using the 200 carb and airbox which is the same size as the 125.
the problem is the bike does'nt have any top end power,it goes flat at 7000 rpm but will rev to 10,000 but with no guts!im still running the bike with the 125 cdi instead of the 200 would this be a problem??
any help would be great thanks..

[KickassKX125]

Hi, whats the jetting like on it? With mine I had to put the jets from the 125 carb and I did get a 200 cdi and a 200 exhaust because as you said it kept falling flat at 7000rpm and losing all power from there, it improved slightly (9000rpm and drop dead) then I did the jetting on it and it would rev to 10000 rpm with some encouragement.

I arn't very impressed with it to be honest because I just can't get it to keep up with my KX125 in a straight line and at the time I raced them my KX had about 120PSI of compression and the KMX had 175PSI so the KMX should have eaten it alive.