Hyobag GT250R & Screaming Demon exhausts - re-jetting?

**DarkLord** · 13th August 2008, 14:28

Sorry if this has been asked heaps before,

I've heard different stories about the Hyosung after-market pipes, some telling me that if I was to just take off the standard pipe and put an after-market one on that I would risk blowing my engine, yet others tell me that putting on a Screaming Demon pipe would be fine and the carburettors would not need re-jetting afterwards.

Can anyone shed any light on this for me? I would very much like a Screaming Demon exhaust on the bike at some stage but I'm not interested in putting one on if I risk blowing my engine! If I do need to get the carbs re-jetted, how much does this typically cost?

Thanks for the advice,

Graham

**Mr. Rock** · 13th August 2008, 14:39

From what i know and have read on this topic, you will be fine upgrading the exhaust to a free flow one without having to rejet. If you were to upgrade the air filter as well to a freeflow one then you would need to look into getting a rejet to avoid running your engine lean. As you would be able to take in more air and output more exhaust gas without being able to supply more gas.

My GT250R has a free flow pipe from Neptune Mufflers on it and its not leaning out or causing trouble. Exhaust note aint to shabby ether

I mean im not a pro tuner or anything, but i do know my bike is sweeeet.

hope that helped a little.

**disenfranchised** · 13th August 2008, 14:51

Originally Posted by DarkLord

Can anyone shed any light on this for me? I would very much like a Screaming Demon exhaust on the bike at some stage but I'm not interested in putting one on if I risk blowing my engine!

I run a SD exhaust, and have not rejetted.
Had a couple of services since putting it on, and the sparkplugs are showing completely normal colouring, and the shop has said there's no reason to do anything to the jets

**DarkLord** · 13th August 2008, 14:55

Thanks disenfranchised,

That's really good to know.

Can you tell me where the best place is to get them from? I've heard it's a website in Aussie or something but I can't find it?

cheers!

Graham

**vifferman** · 13th August 2008, 15:16

I dunno what sort of carbs the Hyo-Silver! And Away!! has on it, but if they're your average CV carbs, and it's running a bit lean, you may be able to get away with either shimming the needles, or lifting them one clip if that's not enough. Both my VFR750 and VTR1000 had non-standard pipes and airfilters, and they were fine after adding shims to the needles - no rejetting was required. (However, Jap bikes often run a bit rich as standard anyway, just to allow for owners fitting non-standard parts).

**325rocket** · 13th August 2008, 20:30

Originally Posted by munta2001

From what i know and have read on this topic, you will be fine upgrading the exhaust to a free flow one without having to rejet. If you were to upgrade the air filter as well to a freeflow one then you would need to look into getting a rejet to avoid running your engine lean. As you would be able to take in more air and output more exhaust gas without being able to supply more gas.

as above

Originally Posted by disenfranchised

I run a SD exhaust, and have not rejetted.
Had a couple of services since putting it on, and the sparkplugs are showing completely normal colouring, and the shop has said there's no reason to do anything to the jets

and above

**Cr1MiNaL** · 13th August 2008, 20:52

After market pipes are not for nobs. Fullstop. One must get knee down first. Even I dont have an aftermarket pipe. Ask anyone.

**Gubb** · 13th August 2008, 20:54

Anyone wanna buy an R6 for a dollar?

**Cr1MiNaL** · 13th August 2008, 20:59

Originally Posted by Gubb

Anyone wanna buy an R6 for a dollar?

FFS I will kill ya if you sell Schnappy, and ask gordon to get his naked arse off her too !

**Gubb** · 13th August 2008, 21:12

They come in a range of options:
Long Carbon Fiber.
Long Stainless Steel.
Shorty Stainless Steel.
Long Iridium Stainless Steel.
Postage to NZ is AU$45. Arrives really quick. The guy is awesome to deal with. If your after something not on this list (i.e. Shorty Carbon Fiber Shorty Iridium Stainless Steel), just ask him (name's Shane), he's a top bloke.

Here's a video of mine:

More info from www.korider.com

**DarkLord** · 13th August 2008, 21:56

Cheers bro. Not something I can afford right now but something I would love to do in the future. Yours is the long carbon fibre one ay?

BTW Raj, what on earth is a "nob"? I assume you meant to say, "n00b?"

**Mr. Rock** · 14th August 2008, 08:54

lol. i think loud pipes are safer than quiet ones.. i mean if people have trouble seeing you.. why not make yourself noticed with noise!

just my thought.. and end of the day its your money and your bike, make it your own.

**DarkLord** · 22nd August 2008, 11:12

Good idea munta2001.

I want a loud bike but I want to get my restricted first so as to avoid unwanted attention from

while riding on my L's with no L plate.

**DarkLord** · 23rd March 2009, 14:07

Woohoo! Just got it fitted... sounds KILLER

It does tend to backfire a bit though. Is that common? I'm going to get the sparkplugs checked in a day or two just to make sure it's not running lean or anything.