FZRSupport: the FZROnline Archive

So this may be a stupid question... If so I expect to get a stupid answer

Been searching around and have yet to find much of anything. Is a mid-pipe is required/necessary. Also, I can't really figure out it's precise function... So if anyone could answer those questions, I would greatly appreciate it. Also, some background info on what I'm doing just in case anyone might need to know in order to give info... Got an FZR600, I'm intending to do a 660 and eventually a 683 mod. Picked up some 99-02 R6 headers to cut, bend and weld (I know their good on the FZR when jetted... not sure if they will be an improvement with the YZF head but I did't quite get that far in my thinking before I bought them, whoops) and I picked up a muffler from a *mumbles* 08-09 gsxr 600 *cough* I like the look so whatever. haha. Plus it bolts right up to the R6 header.

Ickis wrote:So this may be a stupid question... If so I expect to get a stupid answer

Been searching around and have yet to find much of anything. Is a mid-pipe is required/necessary. Also, I can't really figure out it's precise function... So if anyone could answer those questions, I would greatly appreciate it. Also, some background info on what I'm doing just in case anyone might need to know in order to give info... Got an FZR600, I'm intending to do a 660 and eventually a 683 mod. Picked up some 99-02 R6 headers to cut, bend and weld (I know their good on the FZR when jetted... not sure if they will be an improvement with the YZF head but I did't quite get that far in my thinking before I bought them, whoops) and I picked up a muffler from a *mumbles* 08-09 gsxr 600 *cough* I like the look so whatever. haha. Plus it bolts right up to the R6 header.

I,
the mid pipe will only be required if the length of your new system(R6Headers plus your Gixxer (by the way we are not other makes phobic here it it works WTF use it as the guys say ) is NOT the same length as the old system.

Just a tip because I do not know if you have done pipe cut & shut before, the first of the cuts where you intend to "adjust" the pip is to the center line only at the angle you want make the new bend, then you cut across the diameter of the pipe to meet your first cut so removing a segment of curved metal. You then continue the second cut to cut the pipe right thro.

You then weld the segment opposite where it came from and then weld the two sections of pipe together.

You do it that way to preserve the centre line length of the pipe and thus NOT alter the tune of the exhaust system.

Well my intent is to have a shorter exhaust system. So basically... no mid-pipe is needed in that case, correct?

Ickis wrote:Well my intent is to have a shorter exhaust system. So basically... no mid-pipe is needed in that case, correct?

That's kind of a subjective question. As George said it will depend on how you want your exhaust to look. If you're wanting a short exhaust then you may not need a mid pipe. It's really a trial and error thing.

Hope that helps.

Ickis wrote:Well my intent is to have a shorter exhaust system. So basically... no mid-pipe is needed in that case, correct?

A "mid-pipe" is tubing connecting the HEADERs to the MUFFLER.

For cars, this generally also includes the Catalytic converters. Motorcycles, however; may have a "mid-pipe" permanently formed/welded to the HEADERs or to the MUFFLER assembly since they are shorter and easier to install.

Well, I did a "shorty" mid pipe,and a cut down end can on my 1k. Only thing I was considering was the look, BIG MISTAKE!! It did look ok and gave a nice growl but I lost a lot of power and driveabilty. It was impossible to make the carbs work whit it and get a reasonable idle and torque in low revs. After a lot of messing with it I put back the original system,and the carbs to standard settings. And it is a 1000 times better.

So after all size does matter ahem....at least the length of the mid pipe and muffler. I guess that is what YG is saying here.

Something to do with pulses of gases in the exhaust when the valve opens and whatnot.

chefen2006 wrote: I guess that is what YG is saying here.
Something to do with pulses of gases in the exhaust when the valve opens and whatnot.

Yamaha 4stroke pipes were pretty spot on in design, where their 2stroke were for conservative results. Having talked to a couple of their tech guys i realized the pipes were good for the engine in stock form, if you wanted more "oomph" the head & compression would need attention rather than swap out pipes.
HOWEVER the transmission in the FZR is weak and any more ponies would break the drive line so we left it alone and played crafty with the carbs instead.

PS. the only reason I know about the carb funny business is because we were be whooped by Suzuki's at week end street drags and that was effecting sales badly, My little 400 RD ruled 600 & down classes but the 750 Suzi's if ridden well (not always the case) had me at the line so I was allowed to hand over a FZ750 and lo we started to win again.
I took that engine apart only to find that the carbs had a trick and that was all that bike had everything else was factory spec.!!!