a Bandit 400 rear wheel allows you the use of wider tires. Much better, stickier race/sport radial tires are available approved
for the 4" wheel width; you can run 150 and 160 width tires (many have run up to 150 series tires on stock GS rim but it changes
the profile so you can't get to the edge of the tire). Note that the Bandit 400's were only imported into the USA in '92 and
'93 so these wheels may be difficult to find here.
the Bandit cush drive with the GS500 cush drive. This
will make the hub assemble more narrow than stock so spacers have to be made to take up the slack. I used a 3 mm longer spacer inside the cush drive,
and I have about 1 mm of chain clearance with a 150 tire. Make shims to put behind the sprocket
so the chain will clear the wider tire. Add spacers to the sprocket side of the axle until the chain is aligned correctly and then take up any additional slack on the outside of the brake caliper bracket. You also need a 10 mm spacer on the right side, since
the Bandit hub center is narrower than the GS. The other alternative is to machine the bandit cush drive down to fit in the GS swingarm. I prefer to make spacers.