Front End Swap '78 GS750

[jstump63]

I recently found a 2003 GSXR 600 that is being parted out and I was wondering if the front end and the swingarm would swap out with my 1978 GS750? Is there anybody out here that has done this swap or knows what will fit easily? Also, are there any cheaper bikes that would swap. Thanks in advance!

[80GS1000]

Sign into AOL IM, I should be able to answer some of your questions. Screenname is I980gs1000

[tone]

Front end complete will fit with a change of steering stem & some messing with the lockstops but they are shorter than the stock forks

Fitting the rear end will be a bit more difficult & will involve a bit of machining but it can be done reasonably easilly, if its the top braced arm there could be clearance issues & you will either have to go to monoshock or have tabs welded on for your bottom shock mounts

a pic of the swingarm & a measurement accross the pivot point would be usefull to help tell exactly whats needed

[humhead]

The 750 is going to be more work than any other large GS. The triple tree dimensions are different. (Smaller bottom bearing diameter) The forks are also much longer than any other GS & any modern sportbike. The rear is also going to require a lot of work. The swingarm pivot bolt is smaller than the large GS bikes.

I'm not trying to discourage you. If you are a good welder/ machinist it might work. It's not going to be a bolt on.

Terry

[TheCafeKid]

I dunno bout the front end, but i DO know that to get even a GS1100 swinger in my 77 750B i had to drill out the pivot bosses in the frame. Not an overly difficult proceedure, but certainly one that needs carefull attention paid, as, if you get the drill bit waggling in any direction, it will cause massive problems with the bolt running side to side and up and down. You dont want any excess clearance in there.

[tone]

I dunno bout the front end, but i DO know that to get even a GS1100 swinger in my 77 750B i had to drill out the pivot bosses in the frame. Not an overly difficult proceedure, but certainly one that needs carefull attention paid, as, if you get the drill bit waggling in any direction, it will cause massive problems with the bolt running side to side and up and down. You dont want any excess clearance in there.

As i said on your thread mate there was no need to do that new bearing centre bushes would have sorted it :-D

[80GS1000]

The spring rate for a 600 is much too soft for a GS, and those forks are too short. You want GSXR 1000/Busa front end if you want to go this modern. An adapter bearing can be had for the GSXR steering stem to make this swap easy and painless. The rear end can be done but as others have said it's not a bolt on.

[TheCafeKid]

As i said on your thread mate there was no need to do that new bearing centre bushes would have sorted it :-D

Was harder to find the bushes than to drill it. Drilling it cost me nothing, hurt nothing and acheived the same goal.

[tone]

Was harder to find the bushes than to drill it. Drilling it cost me nothing, hurt nothing and acheived the same goal.

Guess i have the advantage of living in the engineering centre of the uk getting this sort of thing made up only costs pennies \\/ having said that i,ve removed & remade/relocated the the pivot point before now just cos i can lol

One solution to the shortness of some gsxr forks is to have a stepped top yoke made up i'm doing this for my efe at the moment :-D

[robertob]

I met a local guy with a Katana that had rsu gixxer forks, and they had screw-on extensions on the ends of the tubes. I've never seen such a thing, but it was a clean way to solve the length issue.

[tone]

I met a local guy with a Katana that had rsu gixxer forks, and they had screw-on extensions on the ends of the tubes. I've never seen such a thing, but it was a clean way to solve the length issue.

again just my opinion but i dont like slugs screwed in as mentioned above on late model forks simply because the wall thickness & hence the threaded part has become thinner in that area due to the factory's trying to save weight from an engineering & safety point of view i'd say its not a great idea

[tone]

Heres a pic of one solution to the short gsxr fork problem, as you can see its work in progress, it is being machined up for a reasonable price by a mate from another forum \\/

[TheCafeKid]

Wow thats lookin pretty good! Id like to find someone to machine an exact replica of my 77's top tree clamp without the barclamps so it was clean looking if i swapped to clipons.

[robertob]

Wow thats lookin pretty good! Id like to find someone to machine an exact replica of my 77's top tree clamp without the barclamps so it was clean looking if i swapped to clipons.

These guys will do it. You might not like the price!

http://www.mginproducts.com/mechanical.htm

[robertob]

again just my opinion but i dont like slugs screwed in as mentioned above on late model forks simply because the wall thickness & hence the threaded part has become thinner in that area due to the factory's trying to save weight from an engineering & safety point of view i'd say its not a great idea

That makes a lot of sense. Wouldn't be fun to have the fork top break right at the threads while cranked over :shock: But I'd think that most of the load is taken by the bottom triple and the top triple (and top of the forks) just keeps everything in place and adds minimal stiffness/strength to the assembly.