I finally finished swapping my rear rim for a CB450 twin rim/tire (Avon roadrider 120/80/18). I enlarged my swingarm to accept a 20mm axel. The CB450 has a much larger rear drum and it makes a pretty noticable difference in braking. The 120 rear tires handles so much better, it doesn't feel lilke it is going to tip over through slow turns anymore...lol. But also at speed it is much smoother. The 120 also looks great as the old 100 looked like a bicycle tire to me.
The only problem I encountered was that a 350f sprocket (and any 350 twin sproket) will not fit on a 450 twin hub. The bolt pattern is a little different. I had to buy a 37 tooth rear sprocket for a 450 twin. I could not find a 38 to match my stock setup. My bike actually has a 400f motor in it, and with the 37, it only tachs about 4000-4200 @ 55. It almost doesnt need a 6th gear...lol. I might go one down on my front sproket to get the low end acceleration back, but this bike cruises effortlessly at 55-70, It needs a new chain anyway...
