from my calculations,(they might not be bang on) a 810 kit with 650 head is about 10.8:1 vs 10.25:1 with the 750 head.
also APE Jay has told me you cant use the 30mm exhaust valves on a stock 650 valve seat. you can however use the intakes. you can get the 750 exhaust valves turned down to 29mm and then they will work. theres no point in going with a bigger valve if the seat cant be opened up enough for it;)
07 MDP Rookie of the Year
01 ZX-12R street/drag bike. 8.97 @155.7 pump gas, dot tires, no bars, no power adders. top speed in the 1/4: 161MPH
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