The VM carbs should work well on these bikes,as they've been used on 4-stroke bikes for years. You can't equate jet size with CCs,as a '73 At[125cc] has a 35 pilot,240 main,and a '73 Dt125 uses the same carb with a 22.5 pilot,and a 140 main. It's got a lot to do with slide setup,airflow,etc. Try...