The 81 and 82 use the exact same crankcase, crank and piston, transmission, and most other bottom end parts.. The cylinder, head and reed valve are different but could be swapped as an assembly.
That carb will be too big for the 125, unless he plans to set it up for top end power only. It is likely a 38mm carb, and 125's normally use 35 or 36mm carbs, except when tuned for top end power only, then a 38mm carb helps with greater flow.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.