Tapered exhaust can

[owen]

Hello everyone, just wondered if anyone had any thoughts on tapered exhaust cans. I took my can apart to cut it down by 4 inches or so and happily cut the carbon tube to length. Then I found the internal baffle has a taper when I removed the wadding. The taper is 50 to 40mm at EXIT. This means I can't just cut it down and reassemble since it would no longer fit the end cap :-/ So my options are to buy a carbon tube and reassemble at full length (500mm) with taper or else buy a 50mm baffle and end cap and make a stubby without taper as originally planned. Any ideas on what's best for a tuned Zxr (75-80bhp)?? Taper or no taper?
Any thoughts much appreciated!
Cheers
owen
PS the rest of the system is a beet 4-1

[cargo]

As ever I might just be being stupid..............but perhaps that taper is there for a reason ? maybe even a performance enhancing reason like it gets you better gas flow and so a pony or two................... why would you want to cut it.............................

[owen]

Hi cargo, the reason for cutting it is to fix it since the end of the carbon can was damaged making the whole exhaust wobble about!! It's already cut now.... Did this before seeing the taper on the baffle... Oops! Now if I cut the baffle it'll not fit the end cap.

Your quite right, it may be performance enhancing, but it may be some other reason such as noise reduction perhaps? Was hoping for some knowledgable guru to be able to tell me what's best performance wise so I can put it back together in the best conguration. I can buy new carbon tube and keep the taper or buy a 50mm constant cross section baffle and end cap and put it back together a bit shorter than original.
cheers
owen

[mick41zxr]

Why dont you buy a new sleeve, alloy or carbon. Akropovic taper all their cannisters, must be for a reason.
78-80bhp is getting up there, why muck around with it.
Regards,
MB

[Alan P]

I'm told Beet (and other manufacturers) did this on their road based race exhausts as a way of reducing noise, but I'm not sure of the truth of this. That said, it does rob a bit of power on my bike and back to back gave me 1bhp with a 50mm straight through pipe as opposed to the tapered Beet.....

[owen]

Thanks Alan. The can has a JMCA badge so i think your right that its almost certainly for noise reduction. I think a 50mm parallel is going to be best
cheers
Owen

[zxr4000]

Gas flows will speed up in tapered pipes. So that's maybe the reason why this one is tapered. It make the system get rid of the exhaust gasses faster..

[cargo]

to taper or not to taper that is the question....................