common misconception my friend. welcome to the boards lol. bore is only telling you how large and heavy the piston is. port timing is what really makes the pipe respond. go on cp industries website, he shows you measurements and pics of his ports, now compare these to your stock cylinders. you see the difference? if you dont let me point a few HUGE differences. 1 being servals are mono block, and have drastically different port design. i dont wanna sounds like a idiot here, but i checked cp website and he dosnt list the serval so i have no idea wat the ports look like but i could assume it has boost ports in both the intake and exhaust. im sure the transfers are larger than stock.... all these things play into what the optimal pipe should be. t5,t6,pt,fmf,pc were all designed and based of off the stock port design, itls alot like putting a ls1 engine in a civic and just because the civics exhaust can be fitted dosnt make it the right choice(obviously not a real comparison).
with that being said, ill say this. my money is with cpi or shearer. why? because these pipes were based off of the cheetah/cub port timings and if you know anything about the serval its suppose to be a less aggressive, more ride able cub witch is achieved by lowering the port timing.
http://www.cpindinc.com/pub/part_list?manufacturer=3