I was looking through my manual & the spec for alternator output is 7amps max @ 5000RPM. I'm not seeing a wattage output. What are you trying to do, run a brighter headlight?
For more output, you could have your stator rewound by an alternator shop, more wire winds=more output, guys with dirt bikes that want to make them streetable do this all the time.
Oh yes, welcome to the boards!