You can get a 114cc jug and piston kit from TB for $149.
Honda Trail Bikes
Or... I have a 107cc high compression kit for $100 shipped.
http://www.planetminis.com/f69/upgrade-kit-86-90cc-imports-107cc-91503.html
Either way, you'll gain MAJOR performance. The stock iron jug and low compression piston are big holdups. Mild porting helps too. You can add a cam for more topend, if you need it.
Honda Trail Bikes
Or... I have a 107cc high compression kit for $100 shipped.
http://www.planetminis.com/f69/upgrade-kit-86-90cc-imports-107cc-91503.html
Either way, you'll gain MAJOR performance. The stock iron jug and low compression piston are big holdups. Mild porting helps too. You can add a cam for more topend, if you need it.