Wider rim and tyre on a GPZ 750

yes i know its a KZ forum - but i regard the old gpz as a KZ.

Anyways. I am trying to make an old bird roadworthy once again and in the process it needs new wheels.
As you know the bike came stock with 130 wide tires. To me it looks to be a good inch and then some clearing on either side of the wheel before it hits the chain or anything else. The rim itself is narrow - so i wonder. What will fit on this old bird ? I have tried looking around the web without success.

Any feedback appreciated. .

btw. its a european GPz - black with red and alu swingarm. I will try to add some pictures when i get back home and perhaps start a project thread . .

Actually, the GPZ750 would have come stock with a 120 rear tire even though 130 will fit the rim. Ed

The early model GPz750 used a 120 tire but the later bikes went to a wider wheel and a 130. Since there is mention of an aluminum swingarm I assume we are talking about a later bike.

Regarding what wheel to install, I have no clue. Maybe the wheels of a ZX-7 or Zepher (if you can find them). In either case you can expect to play the spacer/shim game before everything lines up properly.

The early model GPz750 used a 120 tire but the later bikes went to a wider wheel and a 130. Since there is mention of an aluminum swingarm I assume we are talking about a later bike.

Regarding what wheel to install, I have no clue. Maybe the wheels of a ZR-7 or Zepher (if you can find them). In either case you can expect to play the spacer/shim game before everything lines up properly.

Nessism wrote: The early model GPz750 used a 120 tire but the later bikes went to a wider wheel and a 130. Since there is mention of an aluminum swingarm I assume we are talking about a later bike......

True. I thought he had a KZ750, but you're right, he probably has a ZX750. It would help if he would add his bike's year and model to his signature line. Ed

The chain offset is 100mm measured from the center of the wheel to the center of the sprocket. You should be able to squeeze in a 4'5 rim.
(If the bike is a ZX750A1-3 aka. The Gpz750 -83 -85
//A

hi guys . thanks for replying. i will look into what year it is exactly. I forgot all about pictures last night as i fell asleep on the couch after work. . .

I will try to edit my profile.

Lots of options for the Uni-Track GPz's. and what works on the Turbo and 1100 would probably apply to the 750.

I have one here done by someone else that has an '88 ZX-10 4.00 (?) x 18" rear wheel in it with a 170/60 tire. Axle spacers and the rear sprocket mounting flange were machined to align the wheel and chain with an offset front sprocket - brake rotor was a direct swap, apparently....it is very heavy though.

I would aim at a light weight wheel swap like a newer race - replica 600 - maybe as wide as 4.50 x 17" wheel? Might consider swapping the front to match....

Also - the "Zephyr" 750 and 550 might yield the used parts - but I believe you will still have to machine some parts and / or swap the swing arm, too.

Lots of those Zephyr suspension swaps on this site...cool looking stuff.

random pictures snapped today.
It is in a sorry state indeed. Cylinder no:3 has shot its sparkplug out and the starter clutch is broken. The tires are old and rock hard, break lines started to swell, all rubber is rock hard and cracked on the intake side. Wiring harness has been messed with at some point . there is more .... but i think its manageable.

Can anyone tell from the engine number what year approximately this is .. ? got no papers on it in house. all at the DMV. (get them when i insure and pay road taxes)

I can tell you this without the VIN or engine # - it is an '84 or '85 GPz750 (my money is '85)....being originally black / red.....

The manufacturer's sticker on the steering head tube will have a build date on it.....