Converting motorcycle rear wheel for bycicle?

I have a project in my head for a chopper style bycicle.I just found out i can get my hands on and old beat-up motorcycle the kind that has wheels whith spokes.
what i want to do is use the motorbikes rear wheel on a custom bycicle frame BUT i want to adapt it so that it will accept bycicle free-wheel/hub cassette system so that i can change gears on the bike with a derailer.
Is this posible?what's the best way to do it if it is?i was thinking about doing some work on the bike's wheel hub maybe something involving wealding .......dunno

@your best friend
well i thought of that but u see,they don't make bycicle hubs as wide as motobike tires so i have to find another way,i'm thinking of buying a bycicle hub,taking it apart, and welding or mounting just the freewheel/hub body ( (on wich the sprokets are mounted) to the motobike hub but i dont know if this will work

You might want to contact these people, several of the bikes show MC rims and they might be able to supply the conversion parts.
http://www.northwest-chopper-bicycles.co...

Sure it is possible, but you would have to build up the wheel yourself using a bicycle hub. But, the resulting bike would not be very efficient because the motorcycle wheel will be very, very heavy.

If you are going to make a new frame to fit the motorcycle tire (ie make a long chopper style bike), it might be possible to attach the old freewheel and cogs to the bicycle hub flange side that has the threads to fit the freewheel, and chopping and chucking the rest of the bicycle hub and bearings. Then make a steel shaft to fit pillow block bearings (bearings attached to frame). Weld the motorcycle drive sprocket to one end of the shaft, then install motorcycle chain to motorcycle wheel. The other end of the steel shaft should be welded to a steel disk just big enough to match in diameter the bicycle hub flange (with freewheel attached) by means of nuts /bolts through steel disk and bicycle flange. Make sure the chain line distance from the freewheel and cogs to bicycle chain rings is as long or longer than on a regular bike. Weld a steel tab out from the frame to allow attaching the derailleur in its normal position.