fired up the new 720.
#23
#25
fired up the new 720.
when i get back, i'll try and break it down for you. but there is a lot i got a race head shim under bucket new cams manual cam chain tensioner. plus there is a lot to understand about the kit they resleeve the cylinder and o-ring it the head has to be cut to clear the piston things are pretty tight in there. so some of it i got used from gary, the head was already cut and it had the shim under bucket, but the rest i'll have to itemize. one thing to know is the piston is 13-1 or 13.5 can remember now. which will require race gas. anyways no one else told me about the 105 mm piston not fitting in the head in stock form. so if your checking into this kit check on that. the one thing i can say is it revs faster than the stage two and it gets to 10000 pretty fast. now where the power drops not sure, gary said with the 45 i would be missing some topend, the 45 does work better than it did on the stage two. i have a lot of races setup for this weekend so i'll have a good chance to give a good report.
#29
#30
fired up the new 720.
well the stock bore is 100mm, to get the 720 they bore it to 105, ct tried and couldn't get the head to seal, well gary bored it out to put a steel sleave, samcoe did the same, then he had the cylinder o-ringed, this system works good. when his 760 blew, the head stayed sealed, he said the explosion was so hard it blew the nikasil off the cylinder, but the head stayed good. ok when you go the bigger piston it will hit the head since it is made for a 100mm piston, gary has designed his piston with a very flat top well slightly curved. it allows the burn to hit the top more even if you look at the woods piston or some j&e it is a wedge which can cause different thing that gary would be better to answer. as far as the head work that is up to the person, you can find them used often. there about a 1000. well there is more so gary would be your best guy to answer your questions