so what other motors fit in the GS? info/pics would be awesome

How much time and money do you have? If you have a lot of both, anything.

ha that's about what I figured, just thought i'd ask

Make it a 5/11 conversion with a gsxr1100 engine. That sounds like the most logical option. I bet there's an old gs750 or 900 engine that will fit in there without too much work.

Im not sure but gs450 mill or gs 400 might fit. take al ot of time and money to find out.

Why in the world anyway?

Buddha's done a GR650 Tempter into this frame. Requires some cutting.

Its been said before, but if you want to put a bigger motor in a GS the easy way is to replace everything except the gas cap from the donor bike. That way you have a strong enough frame, adequate brakes etc etc. and the only thing you have to work on is the gas cap. Plus it'll be cheaper.