This is the time of year when I plan what to do for the next one. The chassis including suspension and streamlining is about as good as I can get it. The motor needs a few horsepower so I can go 150 mph. Consultation with Matt Capri reveals I am 10 to 15 horsepower short of where I should be. I need more compression, much bigger valves, and another set of cams.
The cylinder head flow data are below. The intake flow is most critical and it is what I look at. These figures represent the flow through the head with valves, manifold, carb, bellmouth, and air filter attached.
The cams in the bike now have 0.388 inches lift. The new cams will have more than 0.425 Note the flow in CCFM is 209.5 at 0.375 lift and only a very small slightly better with 211.1 CCFM at 0.450 lift. This shows me the higher lift cams will do me no good unless I put in bigger valves.
I cannot afford the valve work so the cams are not feasible. The only option I have left is to raise the compression and to use the cams and valves I have now. Matt says 12.5 to 1 will work and it is about as high as I want to go. I will need to use race gas after this change.