S
Suzuki_Don
Guest
Checking the cam specs shows the 550 uses a 104 cam centerline for both cams. The 650 uses 106 Intake and 103 exhaust. The lift is a positive thing so I'd use the 650 cams and then degree them both to 106, or higher even, if you want high rpm power. I think this will make a bigger difference than the small amount of extra overlap afforded by the 550 cams.
When I got to working out the CL numbers it was a little confusing with the 650 Intakes at 106 and the Exhaust at 103. This is the reverse of normal Suzuki GS practice which in all other motors has the exhaust with a bigger CL than the Intake. So I was not sure why the Suzuki engineers had gone against current practice on the 650 motor. And I was not sure what characteristics the motor would display if I timed it following conventional practice. My settings were 105 Intake and 107 Exhaust. I think maybe Suzuki set the timing back to front on these 650 motors for some environmental or emmissions reason.
Having said that I have been extremely impressed with the power this motor makes and it feels more like a 750 to ride than a 650, in fact this motor feels much stronger than my CB750K2 I had in times gone.
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