Follow the link below for the back story on the 6 speed water cooled 32hp Suzuki GP100 build.
Spent a happy afternoon checking out the balance of the new 48mm stroke NSR GP110 crank and the NSR cylinder port STA's with the 48mm crank.

The crank overall is 12mm wider than a standard GP crank. After setting the crank up and working out the balance weights required for a BF of 50%. I found the Mallory slugs that were fitted to be to heavy but this is good news because I can now keep skimming the inside faces of the crank halves until it comes right. In the end there will be plenty of volume between the crank webs.
Checking out the timing, things worked out much better than I could have hoped for.
With a 15mm spacer the Exhaust is opening at 80 deg ATDC and Transfers at 118 ATDC and the piston just clearing the port floor at BDC.
The deck height is -5.7mm for 0.8mm squish. This all matches the optimum STA's worked out with EngMod2T for this project.
A 15mm cylinder spacer/adapter plate brings the port timing into perfect alignment. (with 115mm RD400 rod, 2010 RM125 piston).
Not bad, a 54mm stroke cylinder fitted to a 48mm stroke motor and the timing works out perfectly.
Great, up until now it was all on faith and a belief that I could overcome any problems with the idea, but now I know it really is going to work.
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