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Main Area => General GS500 Discussion => Topic started by: apbrian112 on February 10, 2005, 05:08:49 PM

Title: custom exhaust
Post by: apbrian112 on February 10, 2005, 05:08:49 PM
just had a question regarding adapting an aftermarket exhaust can (yoshimura, D&D, M4, etc.) to fit onto the gs. i want to fabricate it so that it is a high mount system but was wondering if this would cause problems to acceleration or top speed (if you can call it that :lol: ) there shouldn't be a problem since i'm not changing any of the piping before the b-pipe right? oh, and if anybody has done this mod how much did it cost to get it mounted at a muffler shop. thanks in advance for all the help guys.  :cheers:
Title: custom exhaust
Post by: Dom on February 10, 2005, 05:47:14 PM
I've heard that it'll cost around $200 for a muffler shop to do it.  Might cost more if they have to custom fabricate an adapter flange fpr whatever can you use.  I don't think the rejet is any different than shorter aftermarket cans.
Title: custom exhaust
Post by: apbrian112 on February 10, 2005, 06:07:59 PM
i was under the impression that a jet kit would only be neccesary if you were to get new header pipes as well (as in a full system, not a slip-on). someone correct me if i'm wrong.  thanks...
Title: custom exhaust
Post by: weaselnoze on February 10, 2005, 06:23:49 PM
you are. lol.
Title: custom exhaust
Post by: cummuterguy on February 10, 2005, 07:10:01 PM
apbrian, almost all of your backpressure comes from the can itself.

Basic theory, the faster air can get out, the faster it can get in. So your bike will start running lean(er) once you change the can. You need to re-jet to richen it.
Title: On a GS
Post by: The Buddha on February 10, 2005, 10:53:44 PM
A stock GS is 1 size lean on pilots, 1 size lean on needles, 1 size lean on mix screw and 1 size lean on mains ... stock ...
You open up the exhaust ... you'll drop more than 1size lean ... take the filter out and put in a K&N in airbox you're 2 sizes out ...
So changing the can alone will lean you quite a bit ... whihc is why I have the choker with the flange ...
Cool.
Srinath.
Title: custom exhaust
Post by: apbrian112 on February 11, 2005, 12:06:26 AM
weaselnoze- thanks, you a$$  :nana:  :mrgreen:

so i guess i'll need a rejetting to go along with the new exhaust. thanks guys for the info.
Title: custom exhaust
Post by: weaselnoze on February 11, 2005, 09:41:14 AM
well i have a wileyco can and srinath made a restrictor on the midpipe so i dont have to rejet right away. when i do i just have to knock off the restrictor
Title: custom exhaust
Post by: apbrian112 on February 11, 2005, 12:48:19 PM
srinath- could i adapt one of your restricted midpipes with a muffler of my choice and not have to jet? if so how much for the restricted midpipe?
Title: custom exhaust
Post by: weaselnoze on February 11, 2005, 02:37:07 PM
same as non restricted
Title: custom exhaust
Post by: Frost on February 11, 2005, 02:47:41 PM
when you say 1 size...does it mean by 1 whole number? (ex. 137.5 one size up is 138.5) or by one "size"
Title: Yea
Post by: The Buddha on February 11, 2005, 02:50:28 PM
OK Apbrian - weaselNoz was right. I wasn't charging more for the restrictor if you asked for it at time of ordering. So restrictor or not same $40 ... just let me know.
Frost - 1 size up from 137.5 is 140. Next jet size available.
Cool.
Srinath.
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