So I've been doing something thinking about designing a custom tail for my bike basically taking like a gsxr tail and fabricating it for the gs I've seen the R6 tail but from what I'm seeing the rear seat is not functional. Basically I want to either put the entire subframe from a bike like that maybe even an sv650 or a bike similar I know it would be difficult but I think it could be done.

So what I'm looking for is some help planing it if anyone has a bike they can measure and give me some dimensions and stuff or just any info thoughts ideas I can weld and have access to material.

My original thought was take the subframe of like and r6 or gsxr or something like that with a smaller tail so that it looks good clean lines and stuff and mount it to the gs frame. my thoughts are bend and weld but I think those bikes have an aluminum frame so my next thought was make a bracket to mount it in and kink the sub frame lik how you kink the brake arm for the Kat rear wheel swap.

any thoughts ides plans?

My tail isn't on at the moment, so if you let me know what dimensions you want measurements of, I can probably get them for you.

As far as new subframes.... The sv650 might look better. I think they're probably skinnier than the GSXR tail, and the gs is pretty skinny otherwise. Most newer bikes are going to have aluminum subframes like you said. Most of them will be bolt ons as well, while the GS is welded on. Maybe if you put in the time and effort you could nicely drill the frame and bolt another subframe to it, which would be awesome. My next guess, instead of welding up a new subframe, would be to have someone just weld tabs onto the back of the subframe, then you could just bolt a gsxr/sv subframe right up to it, and you could also make sure they were in the right place so the tail was the right height/angle.

With a little work you might be able to make another suzuki tail fit on the gs subframe, but you'd probably have to attach a couple extra brackets on it somewhere to use the rear seat.

thats the big thing is i want that seat to function and would like to be able to get a nice undertail thats why i was thinking about replacing the subframe and all i also wanted to get a little higher seating for my passanger

I just made the tail I have fit onto the stock subframe, and the problem you run into with the GS subframe is that it's not that far from the rear wheel. I ended up hacking up the stock undertail, and cutting up some sheet metal to add to it. The stock undertail has a very deep wheel well on it. Most bigger bikes have a big enough gap there that it can just run across the bottom and not worry about hitting the wire when you hit a bump, especially if you're looking to ride with a passenger. Otherwise life would have been easy and I would have just taken a flat peice of sheet metal and attached it to the bottom of my subframe.

Do you know how to weld? If you do it might be possible to still use the stock subframe and just alter it a bit. You could lift up the bottom rails a bit, or atleast steepen their angle. They actually stick out of the bottom of my tail how it is now. It'd look nicer if it didn't, but I can't weld so they're going to have to stay that way. After you messed with the bottom you could then just make some mounts to weld on to the subframe to attach a seat like normal, and you would still have a lot of space for storage. I have so much empty space under my tail, but it's a 1-seater, and it's all screwed shut, so I don't have a way to get things in and out anyway.

I'd definitely say your best option is to get tabs welded to the back of your frame so you can just bolt another subframe up to it. Then you won't have to worry about the steel/aluminum situation, and you can the mounts exactly where you need them for whatever subframe you choose. Even if you have to pay someone to do it, I think it'll still be worth the hassle you'd save. The hardest part would be finding some good mounting tabs, but I think a little bit of time with a hacksaw, grinder, and drill on some little blocks of steel and you could come up with something that'll work just fine.

can you guys think of any bikes that have the two up seating that might have a steel frame? I can weld and fabricate whatever i need to I figure the sub frame replacement would be the easiest route to go and still make it functional

I'm going to go a different way. Doing up some drawings at the moment to weld another section onto the gs subframe to mount the 2nd gen sv650 tail to my bike. I didn't like the idea of having it as low as it would otherwise sit, and getting bike parts in australia is bloody rediculous (price wise).
     
Sidenote: I was quoted $230ish  USD for a yamaha r6 rear shock and can get one for half that price shipped from the other side of     the world 

Aaaaaanyway; It's going to have to wait till late October/ early november cause I've got a thesis due, but after I finalise the drawings and actually build it (and see if it works) I'll scan them and put them online so you guys can build one.

I don't remember if I mentioned it in one of the previous posts, and I don't have enough time before I have to leave for work to re-read everything, but most bikes now have bolt on subframes, so you don't have to worry about the subframe being steel or aluminum. Just cut out some mounting tabs out of steel, and weld those to the gs frame, and then you can bolt whatever subframe you want on to the GS frame. Go check out www.customfighters.com if you have any questions about subframe swaps. It'll definitely be more helpful than looking around here, as not too many people have done them here.

I haven't posted anything on my build yet but I am doing exactly what you are asking with a Ducati Monster frame.  I acquired the back half of one and am going to be welding it on this fall.

I don't remember the exact measurement as I took it months ago, but the width of the two is identical down to an 1/8th inch.  Plus I love Monster rears, when you aren't cruising with a passenger you have a nice cowl to put on the rear. 

I am gonna post pics soon as I have almost all of my parts: K9 GSXR FE, Monster rear, etc....

Can't wait to weld!!!

Quote from: O.C.D. on September 30, 2009, 07:03:05 AM
I haven't posted anything on my build yet but I am doing exactly what you are asking with a Ducati Monster frame.  I acquired the back half of one and am going to be welding it on this fall.

I don't remember the exact measurement as I took it months ago, but the width of the two is identical down to an 1/8th inch.  Plus I love Monster rears, when you aren't cruising with a passenger you have a nice cowl to put on the rear. 

I am gonna post pics soon as I have almost all of my parts: K9 GSXR FE, Monster rear, etc....

I'm very interested to see how this turns out. I really want to do a rear end swap, but I'm not sure what bike I want to swap from.

Well, mine came about from seeing what few other bikes had the Monster rear seat.  It looks great IMO on our bikes.  But, everyone just made something work.  Meaning that they did create a new subframe or the like.  I figured if you have to do that anyway why not use a Ducati part.

I have a rear sub frame, keylock, seat, cowl, light, fender eliminator kit for it, signals, etc.............

It has been a slow process gathering parts but now I only need two things: snow and a welder.  Snow is coming so it will be soon.

Do you have any pics of that? I've never seen it before, and I can't seem to find any online. I'm just curious, because I want to know if I should start gathering the parts, too, haha.

Sorry for the thread jacking.

One sec

I thought I didn't have it, but I did.

This was done with paint and is not accurate.  But you see what I am after.  Now add a K9 GSXR Front End and you have what I am doing.

very nice, can't wait to see it in the works.

That's looks awesome. I'll have to see what yours looks like when you have it finished. The passenger part of the seat looks like it slopes away from the bike. I don't mind that, I think it looks sweet especially with the cowling over it, but I don't think my lady would like that, haha.

There is a guy in Brazil that makes a custom 2 up tail for the GS for about $420. It looks like a late model GSXR tail. He calls it a GS500R look up mmottos on here there is some links to his website on here. I'm looking at doing the same thing,  I was gonna order that tail from him he says its completely bolt on and no mods on our end are needed. But I opted to buy a 07 GSXR tail last night and I'm going to see what it takes to mount it up and have the rear seat functional. I'll begin work on it as soon as it comes in cause I want my bike done asap. It should be in within a week thats what they said. I'm hoping that I can make some small mods and have it work, if not I'm either gonna put a GSXR subframe on or sell the GSXR tail and use the funds to get the stuff from mmottos and wait on him to ship. If anyone here has any ideas let me know too. I don't have a problem with getting some tabs welded on to mount a new sub frame, my only concearn would be if the welds break while i'm riding.