GS with undertail exhaust?

[utgunslinger13]

I am in the process of doing a tail swap for my GS and I'm very interested in a possible undertail or underseat exhaust.  I'm horrible with the search function, but I couldn't really find what I was looking for.  I'm curious as to if its been done on the GS, and if so with what tail section?

Specifically I'd also be interested in see a Buell X1 tail with undertail?

Thank you!

[bucks1605]

I've never seen an X1 tail with an undertail, at least not on a gs. Dgyver and D-Day have both done undertail systems.

D-Day's



Dgyver's thread

http://gstwins.com/gsboard/index.php?topic=34220.0

[Jay_wolf]

Theres 2 i can think of  D days , and Dgyvers ,

For the X1 rear end , theres Jim and Gstwizzles

There not underseated

[ben2go]

Check dgyvers build. http://gstwins.com/gsboard/index.php?topic=34220.0

[utgunslinger13]

yeah I've read through all those builds and seen those pics, but I haven't been able to find a stock swingarm with a X1 subframe and undertail exhaust!  Come on people make it easy on me!  Tell me someone has done this before or knows its not possible! lol

Thanks,

Nick

[ben2go]

yeah I've read through all those builds and seen those pics, but I haven't been able to find a stock swingarm with a X1 subframe and undertail exhaust!  Come on people make it easy on me!  Tell me someone has done this before or knows its not possible! lol

Thanks,

Nick

I haven't seen it yet.The problem with under tail exhaust is melting the seat pan and seat.I may do the X1 tail on a GS I have with a bent rear frame.Thought about using 2 of those polished stainless steel 3 inch diameter glass pack mufflers.Mount them side by side.

[yamahonkawazuki]

would installing some sort of heat shield help wiht teh seat pan?

[ben2go]

would installing some sort of heat shield help wiht teh seat pan?

Some.Dgyver discovered that carbon fiber cans do not conduct heat well and helps cut down the risk of a melt down.

[utgunslinger13]

How do the manufacturers combat this meltdown problem?  Is it that they use a special exhaust combined with a heat sheild? Or I'm sure there is some compound you can coat the bottom of the seat pan with and combined with a heat sheild should help this issue?  I've never torn apart a bike with an undertail exhaust to see whats protecting it so maybe I should be going through bikebandit's microfiche for parts ideas!

[dgyver]

I have seen less than 6 undertail exhausts on a GS. With a Buell tail has not been one of them.

Factory undertail exhausts do have heat shields, go to a dealer and see what they have done.

I used the stock pan and lock location so I could still lock the seat to the bike. I had to cut away the center of the pan and some of the foam to have enough clearance. Also, there is not a rear seat. It has been cut away for clearance of the muffler. I guess you could call it a Monoposto since it does have a Duacati midpipe. The subframe was modified for clearance of the midpipe.

I am going to add a shield to limit the amount heat the seat is exposed. There is now about 2-3" gap between the top elbow (before the muffler flange) and the seat. Installing a shield about 1" above the pipe should work fine. I am planning using a combination of aluminum and possibly carbon fiber, unless I can find some other type of material that can handle getting wet... I have a couple of other ideas for materials. The problem with carbon fiber is the epoxy (used to hold its shape) which is the limiting factor with heat. The muffler does fine since it has the fiberglass packing as a heat insulator.

[Fry]

I'd lay down some type of Car Based Foil Backed sound deadening material on the bottom of the seat, as well as create a thin aluminum heat shield, along with using dual carbon cans. I'm currently trying to talk myself out of the idea of using (2) Stock ZX-10 Silencers with factory shields built in, or some cheap MX silencers.

[bucks1605]

I'm currently trying to talk myself out of the idea of using (2) Stock ZX-10 Silencers with factory shields built in, or some cheap MX silencers.

You shouldn't have told us... now we're going to talk you in to it. 

[Fry]

I'm currently trying to talk myself out of the idea of using (2) Stock ZX-10 Silencers with factory shields built in, or some cheap MX silencers.

You shouldn't have told us... now we're going to talk you in to it. 

Well I gotta make "utgunslinger13" happy, he keeps reminding me how my new upper sub frame rails stick out like a sore thumb. So I plan on mounting dual Silencers, each being hung / mounted so it covers this rail, so they technically wont be under tail, they'll be Half Under Tail/Half Outside Tail exhaust. They could be mounted in suck a fashion that they follow the seat rake, perhaps 1" down from the seat base. The part that gives me the Willys is going from the collector tubes, up to the silencers, I don't know how, or which way I would go? I could run them like the old Honda Scramblers that had the high pipes, or I could snake a single pipe up the brake side of the frame through the area created by the upper and lower sub frame rails, make a 90 degree bend to the back, then form some sort of Y Pipe to connect to the silencers? Or I could just run 2 pipes back behind each foot peg and bend up with a sharp angle connecting to each silencer, without snaking under the sub frame?

Damn You Guys I have to much other stuff to figure out and get done, plus I don't like the idea of running to the local garage that has a tubing bender, hoping to get things right, right off the bat....

[utgunslinger13]

I hope you didn't take that as giving you a hard time!  I was just curious cause everything else looked really good and I had no idea what you could do to cover that!  The dual high-mounted exhaust might be a perfect fit!  Definetly can't wait to see that!

Nick

[Fry]

I'm just busting on you, trust me I'm very frustrated with the way those uppers are visible. I'll be able to shave a bit of the seats plastic mounting bosses down a bit to get it to cover a bit more of the rail, especially closer to the tank, a set of Dual High Mount Cans should cover the rest. I do worry about passenger and rider heat issues though.

[Trwhouse]

Hey there,
This is starting to sound very cool, the idea of using a pair of ZX-10 mufflers on a GS500. Have you mocked it up yet to see if it would work?
It has to be cool to have a welder in your garage to be able to fabricate anything.
When will you have pictures of this that you can post?
A very cool idea.

[Fry]

I havent even bought them yet and don't know if I will.

[Trwhouse]

Those are cool!