Yet Another GS/GSXR Hybrid Project.

[Quasimodo]

Hello everybody. Just testing the water here and making sure whether this is the right forum to post my questions as I transplant the front-end from a 1991 GSXR1100 to my 1983 GS750E. Currently I'm only planning to do the front-end and leave the stock rear.

No pictures at the moment as I haven't started, yet.

So, if this isn't the right place for it, please let me know. If it is, here's my first question: I need some sort of a handlebar riser to allow for a more upright riding position. The stock GSXR clip-ons along with the shorter forks would make me stoop over the tank too much, and it'd force me to either re-route many cables or order custom shorter ones. I know about the LSL Superbike Riser Kits, but they're rather expensive and quite hard to find, at least for this GSXR model. I'm hoping that there's a top clamp from another bike that would fit and, even better, already offer a taller position. Is there such a thing? The diameter of the GSXR fork is 52mm.

Thanks.

[salty_monk]

You'll want to at least fit a 4.5" GSXR wheel in the back so you can run radials at both ends. Bike will be unstable with Radial front & Crossply rear.
Plenty of room for the 160 tyre in there. With a custom Brake mount (I can give you a PDF file of this so you can have it made or drill & shape it yourself) to mount an earlier model GS caliper (with the Banjo bolt on the back) & a custom (I have one of these you can buy) torque arm it's a pretty simple process.

You'll probably have to put a spacer behind the front sprocket or use an offset sprocket & also run a 520 setup.

This is the wheel you want: http://www.thegsresources.com/_forum...d.php?t=156160 - this is my for sale thread.





This is the kind of thing on the arm. Actual shape is a bit different.


Here's my bike - I used a 5.5" rear wheel but it was LOADS more work to fit.



Can see the brake in this one:




and in the Video.. still "curing" the paint on the pipe in this one!



Mine is a RSU GSXR 1100 front end. Sounds like yours is USD. You can run a Honda CBR top triple to gain a bit of extra height. Drill the top tree plate & fit risers & a standard bar, plenty of people have done that. I got some custom bars bent up with some rise in them to use in the GSXR top triples. The ones in the pics were 4" & were not strong enough so I have switched back to some 2" ones made with 2mm wall thickness steel tube then powdercoated. It's a little more aggressive than stock (about 2" lower but I managed to get them a bit further back).

Good luck with it!

Dan

[Quasimodo]

First of all, thank you very much for the detailed reply.

Second of all, I've got a few more questions below based on your response.

You'll want to at least fit a 4.5" GSXR wheel in the back so you can run radials at both ends. Bike will be unstable with Radial front & Crossply rear.

Silly question, how unstable? Unsafely so?

Plenty of room for the 160 tyre in there. With a custom Brake mount (I can give you a PDF file of this so you can have it made or drill & shape it yourself) to mount an earlier model GS caliper (with the Banjo bolt on the back) & a custom (I have one of these you can buy) torque arm it's a pretty simple process.

Just to be clear, do you mean to say the 4.5" wheel will fit into the stock GS750 swing arm? The reason I'm asking is because I've neither fabrication skills nor, at present, facility. At least not that I can find for the latter. So, if something doesn't bolt-on, it'd be a problem.

Yes, please send me the PDF file. It may come handy later on. Thanks.

You'll probably have to put a spacer behind the front sprocket or use an offset sprocket & also run a 520 setup.

I've seen some pictures of offset sprockets around here, where can I order those from?

This is the wheel you want: http://www.thegsresources.com/_forum...d.php?t=156160 - this is my for sale thread.

I do have a rear wheel from the same GSXR1100, but I don't know what size it is. If it's not a 4.5", then I may be contacting you about the one you've got.

Here's my bike - I used a 5.5" rear wheel but it was LOADS more work to fit.

Very nice. It'd be easier to just buy yours. You selling?

Just kidding.

Mine is a RSU GSXR 1100 front end. Sounds like yours is USD. You can run a Honda CBR top triple to gain a bit of extra height. Drill the top tree plate & fit risers & a standard bar, plenty of people have done that. I got some custom bars bent up with some rise in them to use in the GSXR top triples. The ones in the pics were 4" & were not strong enough so I have switched back to some 2" ones made with 2mm wall thickness steel tube then powdercoated. It's a little more aggressive than stock (about 2" lower but I managed to get them a bit further back).

Good luck with it!

Dan

Yes, they're USD forks. I'll do a search later, but do you happen to know which year and model CBR would work?

Thanks again.

[Guest]

I've got a gsx600f front end on my '83 with a 4.5 rear wheel with a 160/60 Dunlop roadsmart radial with the stock swingarm. (and a Hagon monoshock) If you do the front end you need to do the rear too. You'll love how much better it will corner....

[Quasimodo]

I've got a gsx600f front end on my '83 with a 4.5 rear wheel with a 160/60 Dunlop roadsmart radial with the stock swingarm. (and a Hagon monoshock) If you do the front end you need to do the rear too. You'll love how much better it will corner....

All right, you talk me into it.

Some questions on the details:

1. I take it I'll need an offset front sprocket like Dan said. Where can I get one of those? And how much (i.e., measurement) offset?
2. What about the torque arm/bar? Did you make a custom one also? Or, did you do something different for your rear brake?
3. Not related to the rear wheel, what'd you guys do for the clocks/gauge? Use a stock set that matches the front-end or a 3rd party one like Acewell?

Thanks.

[salty_monk]

Will answer your questions in turn.

Yes if you don't do the back wheel too it will be unsafely unstable!

Yes the 160 will fit the stock swingarm. You will have a 5.5" wheel like mine but that will NOT fit the stock swingarm without loads of work to gain clearance.

1. Maybe... I have just a 6mm spacer & running a 530-520 conversion sprocket (the one with the lump on the side) with the lump on the inside not the outside as it's meant to be.

2. Torque arm/bar is custom made. I have one of those spare (had 2 made) that you can buy for $30 plus postage.
Wait till you see what brake rotor you get before I send you a PDF as there are a couple different diameters. The one shown in my pic above is the best one for the conversion I did as if you use the smaller one (as on my bike) you a. lose power & b. have to grind some parts on the caliper to create clearance.
This conversion requires an older GS1000,GS850 caliper that is plentiful & cheap (or with the bigger rotor to me you might just have enough clearance to use the stock 750 one where the banjo bolt fixes on the side of the caliper.

3. I made a custom plate to mount the ignition & clocks but it will be different to yours. I am going to fit an Acewell or http://www.kosonorthamerica.com/ one of these in order to overcome speedo accuracy & space behind the fairing issues next.

It's yours for $6k if you want it

[Quasimodo]

Yes the 160 will fit the stock swingarm. You will have a 5.5" wheel like mine but that will NOT fit the stock swingarm without loads of work to gain clearance.

Dan:

Please check your PM about the wheel you've got.

Maybe... I have just a 6mm spacer & running a 530-520 conversion sprocket (the one with the lump on the side) with the lump on the inside not the outside as it's meant to be.

Would you happen to have a picture of this? I'm not sure I've understood this correctly.

It's yours for $6k if you want it

That's about $8K more than I can afford.

I've got a gsx600f front end on my '83 with a 4.5 rear wheel with a 160/60 Dunlop roadsmart radial with the stock swingarm. (and a Hagon monoshock)

KingOfVenus:

Do you also run a 530-520 conversion on your bike?

Just curious.

I'm most probably going to start the conversion work in the summer when it gets a bit hot to ride where I am (AZ), though I may mock up some of it in the next few weeks.

Thanks.

[salty_monk]

520 conversion gives you more room between frame & tyre. You may not need it with the 160 though....

I can prob give you the brand & the part number for the sprocket I used!! Chase me up on it as I'll have to do some digging.

Sent you a PM back. I have a new 16 tooth 520 front sprocket but it's a JT not the one I am describing.

Spacers are cheap from Z1 enterprises. You have to grind the sprocket nut down a bit & use threadlock rather than the lock washer but it works ok.

Dan

[steve murdoch]

Dan, when you are digging around for the sprocket info could you also check for the spacer #/info. I could not find anything on the Z1 website.

[salty_monk]

Used their search function... "sprocket spacer".

http://www.z1enterprises.com/SearchResult.aspx?All=True&KeyWords=sprocket%20spacer

I used the 6mm one. It's a simple part but the inner dia is a funny size & needs to be exact (out dia is not so important) so hard to find anything local (but easy to make if you have a lathe).

Dan

[Quasimodo]

Just thinking through some of the details at a high-level. For instance, brake lines. What would be the best thing to do? I know I'd want stainless steel braided lines, but should I try to source pre-made custom ones or just get the necessary bits from http://www.anplumbing.com/shop/ or so and make them myself?

Also, the handlebar risers. Any idea which year and model CBR top clamp would fit 1991 GSXR1100 52mm forks?

Thanks.

[Guest]

Dan:

Please check your PM about the wheel you've got.



Would you happen to have a picture of this? I'm not sure I've understood this correctly.



That's about $8K more than I can afford.



KingOfVenus:

Do you also run a 530-520 conversion on your bike?

Just curious.

I'm most probably going to start the conversion work in the summer when it gets a bit hot to ride where I am (AZ), though I may mock up some of it in the next few weeks.

Thanks.

530 with no offset at all.

[salty_monk]

That's the easiest way then... you definitely have room for a 520 setup with no offset on the sprocket if you want to use that 520 sprocket you bought off me with the wheel.

I also have a 16 tooth 520 JT front sprocket that you can have cheap if you want it but with that rear I would probably go with a 17 tooth personally.

Dan

[Quasimodo]

That's the easiest way then... you definitely have room for a 520 setup with no offset on the sprocket if you want to use that 520 sprocket you bought off me with the wheel.

I also have a 16 tooth 520 JT front sprocket that you can have cheap if you want it but with that rear I would probably go with a 17 tooth personally.

Dan

That sounds very promising. I'll see if I can mock-fit the rear wheel some time this weekend and post some pictures.

Thanks.

[Quasimodo]

530 with no offset at all.

Thanks for the info.

Would you mind sharing some details on your rear wheel set up? Because it sounds like exactly what I want to do. For instance, do you use the stock calliper and torque arm? How about the rear sprocket? Do you have to add/remove any spacers or anything like that to make things align properly? Anything else I should be aware of?

Thanks again.