17 Front wheel on a 79 GS 550

[Old Colt]

The thread has gone hiding on me about later wheels on an early bike. Well here is my answer.


This is a 1994 GSX wheel on my 1979 GS550 forks. I used the original axle and spacers from the 550 with a wheel and speedo drive from the later bike.
The brake rotor at this time is a 2005 GSXR 600. This gives a 300mm rotor. The rotor has a bit different 5 bolt circle than the earlier wheel so that needs to be dealt with. I have a pair of rotors coming that I will get on soon.
So for those that say the later wheels will not go on early forks. I do not know why not.

[TheCafeKid]

Sweet! Im not sure that was really ever a question, the bigger question is: What are you going to do about the rear??

[Old Colt]

I just found the other thread under appearance mods asking about modern wheels on an early bike.

The rear of this will get a 4.5" wide rim, I have a couple of them in the shed and they pretty much are a simple swap.

[Mark M]

Old Colt,

How wide is that front wheel?

Thanks,
Mark

[Old Colt]

Hi Mark,
It is good I checked before I wrote, It is a 3" wide with a 110/80-17 tire.

[Mark M]

Hi Mark,
It is good I checked before I wrote, It is a 3" wide with a 110/80-17 tire.

Do you think a 3.5" would fit as well?

Mark

[Old Colt]

On a 100, yes for sure, on a 550- 750 the 120 tire may depend on the fender mounting. This tire is close to my clamp on fender but is quite acceptable.

I do have a late 3.5 rim here and it would not take long to turn up some spacers to fit the large bearings to the small axle.

This wheel I got is a Kat rim, Is the GSXR rim of similar vintage a small axle with 3.5"?

I had just bought the first one that came along.

[badbrown]

Sweet deal! I knew it could be done. Please post more pics of front and rear after. I plan on doing this on one of my basket case 550's. Thanks for the thread. I have a pair of Katana wheels to go on the junk 550. You beat me to it though.

[Old Colt]

Hi BB,
I am looking at two options for the front rotors at this time.
When or if the front rotors I just bought on ebay arrive,( appears I found some scum there)
1, I will remachine the bolt circle so the mont up to the early wheel. This will require a spacer to move the caliper inwards. Being the calipers need adapting this will allow that to be done as a bolt on.
2, Another option is to machine up a pair of spacers moving the rotors out to where the calipers want to be.
These spacers will have two bolt patterns, one fitting the wheel and the other the rotors.

I am also keeping my eyes open for some 300mm brake rotors that will bolt up to the wheel that are flat or have a slight offset.

On the rear, it turns out the rims I have here are the 3.5" wide Kat wheels. I was thinking they were 4.5". Not.
Either way they will hold a 150 tire better than the original rim. I need to address the chainline. The sprocket carrier will not interchange with the early rim and what I have here is about 3/4' to wide. The casting will not allow ne to narrow it as far as needed but I can narrow that down a bit and run an offset front sprocket. Doing so I may be better off with a wider rim to utilize the space available.

Another little item is that the speedo cable is to short. I have GS1000E fork legs and unless I limit there travel back to what the 550 originally had the speedo cables are just too short. This will be true with 750 forks also. I expect this has been solved previously.
I do not expect this to be an issue with the 19" wheel. That speedo drive uses the threaded lower cable end, I can get longer cables for them.
The later wheel has a slip in with a screw to retian the cable, I need to find what cable is a few inches longer than what came on the GSX.

[nastyjones]

So will a 17" gsxr wheel fit my 80 1100? If so, how did you work out the brake details? What did you end up with?

[Old Colt]

Yes it will go on your bike.
I have not finalized the brakes, I bought a pair of rotors on ebay and the seller decided he did not need to send them, so I just filed the claim but will need to get a set still.
I intend to use a pair of 2004 GSXR600 rotors, they are 300mm flat rotors.
In my app I will need about 6mm +/- spacer adapter to mate the rotors.
Yours will want a thicker spacer or space the calipers inwards a bit.

There might be a slightly dished set of rotors that might do the job but for now I am going with what I can build.

[nastyjones]

So I'll need a 3-3.5" wheel of similar vintage so I can use a mechanical speedo correct? What year wheels will fit? Then I would need to make sure wheel, rotor and caliper are from the same year. Does this all sound right?

Paul

[Old Colt]

Hi Paul,
You can fit a 3.5 in your bike, the 550 & 750 will be quite tight at the fender mounts with a 120 tire.

I think the rotors that came on the wheel will be a bit wide to clear the forks. I unfortunately do not have the larger set of triple trees here to mock up a setup for you. It would be great information for many that want to retain their original forks.
If you could get me a measurement of the width your caliper mounts I could estimate a setup for you.
The wheels I have worked with are from the oil cooled bikes. I expect any wheel that has the speedo drive will go in with little fuss. The wheels without the speedo drive are quite a bit wider at the wheel bearings. I do not think they would be a simple matter of turning up some spacers, they will need the later / wider fork spacing.