GPZ550 1981 Rear wheel swap / swingarm

Hello:

I'm new to this forum and encouraged to see so much hard to find information. Forgive me if these questions have been answered elsewhere but I have not found what I'm looking for.

I have a 1981 GPZ550 D1. The rear wheel is stock 18" skinny and locks up easily. I'd like to use a wider wheel tire/combo, a 120 or 130. I've located a 16" rear off I believe an LTD which visually looks identical to mine (sprocket, brake disk, etc.) except for width of rim. With a 120 width tire I think I'd be close to the left front side of the rear tire rubbing the swingarm, and a 130 would almost certainly need swingarm mods. So I think I could use the LTD 16" wheel (what would that do to handling?) with some swingarm mods.

If I'm going to all that trouble I see others have swapped in aluminum swingarms. Does anyone who has done this have suggestions as to what swingarm and wheels (lighter mags if possible) would fit on the 81 GPZ550 with minimal mods? I'd be happiest to end up with a fatter tire and lighter bike.

Also - the bike was dropped on the left side, looking for an undamaged left front engine casing if anyone has one.

Thanks
Ronm

120/80-18 works fine on the stock wheel . Something like a Pirelli Sport Demon is more than sticky enough . If you have a nice '81 GPz550 I wouldn't start hacking it up , they are getting hard to find .