'81 550 GPz wheels

I have been told that it would be a good idea to replace my '81 seven spoke wheels with lighter '82 five spoke wheels. Has anybody done this? Any ideas or advice?

I decided to go ahead and do this. I found some '82 five spoke wheels, sans roters. Front was 12 lbs. rear 14 lbs. My '81 wheels weighed front 14 lbs. rear 17 lbs. This is a significant reduction in unsprung weight! :laugh: Only problem is that my seven spoke roters have a different bolt pattern. :ohmy: But, I found a set of "82 roters and they are on the way. :whistle: I will report back when everything is bolted back together.

Post edited by: cpgpz, at: 2006/12/09 12:24

I am replying to my own post to get it re-posted. Obviously I need to learn how to navigate this forum.

will your calipers and mounting brackets work with the differant rotors?

cpgpz...why are you so interested in the 5 pound weight savings? Are you into vintage racing or something?

www.gpz550.com/gpz550/

There are some racers on the GPz forum if you are interested. Click on the "messages" tab and you'll see a link to the "discussion forum" which is searchable...enjoy!

Post edited by: neilage66, at: 2006/12/09 16:04

OK,I'm finished with this project. It turns out that the '82 wheel assemblies are 2 lbs. lighter in front and 4lbs. lighter at the rear. This is unsprung weight, so I believe that it is wourth it.

I have about 300 miles on this bike since the change and everything works. I had to use the '82 brake disks; the '82 axel spacers; the '82 sproket hub and the '82 speedo drive. My thanks to the guys at Rice Paddy for finding all this for me.

The '82 disks are the same size as the '81's but have a different bolt pattern because of five spoke wheels instead of seven. The '82 spoke hub is also down sized from the '81 but uses the same sproket.:whistle:

I am a racer, but I race vintage sports cars. I have never raced a bike at a race track.

Glad things turned out well with the conversion.

What kind of "vintage sports cars" do you race?
Just curious, and we like pictures too!

Vintage car pics would be great.

I'd be interested in knowing if this swap could work on 77-80 KZ650s.

Got pics of the bike too?
Before and after.

Could you measure:
1.The dia. of the discs, front and back? Is it dual disc up front?
2. The distance between the front discs, centre to centre.
3. The thickness of the discs, front and back.
4. What size rims, front and back?
5. What size axles do the GPz's use?

Post edited by: rstnick, at: 2007/01/02 22:14