yesterday arvo had a lil play with my buggy .. got the SM.21 tuned in real nice .. the things a screamer and after a full tank of being driven hard just sat there idleing .. ha love it... now i had a look at the pipe that im running and its a 9886 novarossi pipe .. dunno if it suits this engine but judging from what AMAIN has on its site its a top end pipe with ok bottom. dunno how i pipe can be good at both lol but any ways , if its a top end pipe thats wat i wanna stick with SPEED! :P . also when i got the engine it had a fin broken off the MAG head ,then i broke one off it yesterday , i think because of it being MAG it does not hold up the best to lil crashs .. so might look for a siro head or orion alpha head to swap it out .