Moped Army

The guy at Mark's Motor sports phoned me and said that the brand new clutch installed, still prematurely shifted and rattled excessively during the shift uphill.

I gave him a clutch with a shortened spring and chamfered leading edges of the clutch material.

I told him if it doesn't work out.....
change the front sprocket so it will be above 9mph when It shakes and shifts at about half throttle.

This is my last resort.

If I go up 2 teeth on the front sprocket and down 1 on the back, will the torque still be reasonable.

This bike always has a passenger, my girlfriend, we tour on it.
Any Ideas.