1979 KZ750 Rear Wheel Question

So I was curious what size is of the factory 79 750 rear spoked rims? I want to convert mine possibly to a wider aftermarket excel rim. I believe mine is a 18" but would like to switch to a 17x5 rear rim to give me a little extra tire. Ive done some work to my motor and all it likes to do now is spin the hell out of it. Would I need to change the hubs? If so does anyone know where I can get them at?

18x2.5" I believe, and you won't be able to use the stock swing arm.

What have you done to your motor? It's rare to hear of a 750 twin with so much power.

Slippery slope. The stock rear rim is only 2.15" wide; a 5 inch rim will be using a 7 inch wide tire. I believe lacing a rim that wide to the stock hub will result in the chain hitting the tire unless you change the hub so the chain is further from the center, and it will require an offset counter sprocket and an engine cover (probably with a bearing). Also, going that wide will very likely result in the chain hitting the frame which would require a rather creative solution. Also, as Steell pointed out, the stock swing arm will be too narrow.

Like Steell, I am surprised your 750 twin is making that much power. It's possible that the tire spinning is a result of a poor quality tire or the wrong size tire. What size and brand/model is on there now, and how old is it (they sometimes harden up quite a bit with age).

Of course, it could be operator error; are you launching from red lights at 9,000 rpm? :laugh: :laugh: :laugh: Ed