From:Mutt Electronic:pigstye13 -A-
Subject:RE: carburetor in the stu and st bikes Date:Thu Mar 3 19:28:00 2011
Response to:15396
Sorta. the 53-58 S/STU uses the same cylinder,but a restrictor plate was used in the carb mouth. The i.d. of the intake is right at 13/16" (.812) But from 59 and on, the intake port was reduced to 5/8" (.625) i.d. to make it harder for the kids that bought the bikes to cheat.


is the difference in horsepower between a st and stu only in the carburetor???????????? or more to it..