Thanks.
The dual carb setup looks remarkably like the future S&S Dual Throat manifold. Can't tell from the picture whether the 2 mixture streams merge in the manifold (each carburetor supplies 1/2 of the flow to both cylinders) or are completely separated to the individual ports (each carburetor serves only one port)?
Assuming the 1-1/4" carbs are the common M-51 etc. size, the combined 1-1/16" venturi area is 1.77 square inches vs. the OEM M-74 with 1-5/16" venturi at 1.35 square inches, +31%. Comparing the throttle areas, the M-51s total 2.93" vs. 1.92" for the M-74, +53%.
If each only supplies one cylinder the carburetors are way too small, as was the S&S.
The flywheels pictured are certainly not 105" - the crankpin is much too close to the shaft center. They don't give the stroke length, but with std. bore even 5-1/2" stroke is only 102". We can assume that the bore of the original barrels has been increased!
The dual carb setup looks remarkably like the future S&S Dual Throat manifold. Can't tell from the picture whether the 2 mixture streams merge in the manifold (each carburetor supplies 1/2 of the flow to both cylinders) or are completely separated to the individual ports (each carburetor serves only one port)?
Assuming the 1-1/4" carbs are the common M-51 etc. size, the combined 1-1/16" venturi area is 1.77 square inches vs. the OEM M-74 with 1-5/16" venturi at 1.35 square inches, +31%. Comparing the throttle areas, the M-51s total 2.93" vs. 1.92" for the M-74, +53%.
If each only supplies one cylinder the carburetors are way too small, as was the S&S.
The flywheels pictured are certainly not 105" - the crankpin is much too close to the shaft center. They don't give the stroke length, but with std. bore even 5-1/2" stroke is only 102". We can assume that the bore of the original barrels has been increased!
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