I have posted this before about fit a performance exhaust for my Suzuki CS50 1982 50cc, well today I had a new performance with large Expansion exhaust from Honda PX50 something like that and it was modified by a welding to fit my engine gasket head, the top speed has increase from 31.4mph to 33.5mph I was disappointment with the result. The scooter it have a performance air filter, it has lost 3.2kg of kerb weight. Before the original performance from my 50cc it was 28.8mph so I have gain 4.7mph more. I am try to get other 5mph more if it is possible. I can someone tell me if I can swap my Mikuni VM14SH carburetor to a large carburetor? if is not possible would my current Mikuni VM14SH the main jet it has 85 size jet, would it work to get more mph if I swap for jet number 92? Kind Regards Fab.