If you want mileage, get a new 4 stroke and leave it stock. Having a banshee and expecting decent mileage is like buying a massive truck to haul with a V8 and wondering why it can’t make it past a gas station.
Please use the following link to access the complete Yamaha Banshee 1987-2006. This is on Media fire and is available for download. Must have PDF to access and download. If there are any questions please feel free to message me.
Adam
Added a few manuals:
Honda TRX 450R 04/05
Honda TRX250R
KFX 450R