i just ordered new parts for the 200cc airboat. A new high torqe cam .252 lift thats the biggest i could go without modifing the block,a flat top piston, a 22mm mikuni carb,billet flywheel,and billet rod. i should get 15+hp@6000rpm out of this motor. it will prob get here tuesday but im going to S.C. on monday for the week.
and I think its cold here in FL :|

Have fun, I ran a modded BS opposed twin for a while before it let lose.

im hoping the billet rod and flywheel help it last a lil longer that is the weak point of this motor.i got the boat up on plane the other day next to the bank but it came back down in the deep water.hopefully this extra power will get the rpms needed to keep it on plane if not i guess ill put it on my mini bike and try my oppossed cyl 16hp b/s but it is very difficult to find aftermarket parts for this motor

well im not goin to SC this week so i can install my new parts they should be here today.I used a timing light for a tach yesterday and found out im spinning the motor 5080rpms max right now with stock cam and carb. the cam i bought only pulls till 6000. Do you think another 1000 rpms on the motor only 500rpm on prop will make a big difference?

well it made a big diff, my gear box wont even stay together now i welded it solid now but havent tried it yet. i made a big mistake :oops: and ran the motor without the prop to see how many rpms i could reach without the prop it spun 6500rpms and floated the valves the valve broke and went through my new flat top piston my valve springs were only rated up to 6000rpms.after that happened i realized it had no oil when i reved it to 6500 but it didnt score the wall to bad nuthing a cyl hone didnt fix.
but it did get my boat on plane and kept it up when it was running.spinning at 5800rpms with all the new mods and it revs up like a 2stroke now