Anatomy of a Hayabusa exhaust system

Because it is a work of art. It is made of the finest materials, adheres to proven theory, barely affects performance, is quiet and meets the strictest emissions tests. The only compromise is weight....

I recently cut up a set for a separate project, thought I might share my findings. I could help but think that some engineer in the might Suzuki works got an internal award for his efforts. Or maybe a cup of saki in a plastic cup.

Firstly, the headers. They contain a carapace within which is another stainless steel shell holding two catalytic converters. Some high tech insulation is sandwiched between the two shells.

[Image: CatalyticConverters001copy_zps6de14add.jpg]

The above image shows the position of the stock narrow-band oxygen sensor, the wide band was fitted by myself for logging purposes.

Here's a close-up of the cat. Unlike the ceramic matrices you find in cars, this one is metal. And heavy!

[Image: CatalyticConverters003_zps558b2a16.jpg]

Here is a close-up looking into the incoming headers. The second stage pipe diameter follows traditional exhaust ratios, in this case 1:1.5 of the headers, i.e. the cross sectional surface area of the stage two pipe is 1.5 times that of the two headers that feed into it.

[Image: CatalyticConverters006_zps412c4012.jpg]

Not the smoothest transition, but far better than aftermarket pipes I've seen.

Now for the mufflers....

[Image: Tackwelded001_zpsdf01997c.jpg]

First, a cutting disc on the Dremel to remove the tack welds on the retaining screws.

[Image: TackWelded002_zps6e0e8295.jpg]

Just look down the other end to get an idea of whats inside.....looks like one of those lines you have to wait in at the bank lol!
Smoke me a kipper I'll be home in time for breakfast
That's interesting stuff, mate. Does the coating on the baffles wear off after a while, or does it just get covered up with deposits? Does the coated stuff have any scrap value - it's platinum, isn't it? Is it poisonous in any way if you touch it, or inhale any dust? Waiting for your next installment! Rob
Platinum? apparently, I would like to confirm but its outside the scope of my objective, maybe someone could provide some detail. I just know they burn at extremely high temperatures and the proximity of my wide-band sensor to the hot cats may have been screwing with my readings!

Anyway, Cap off..
[Image: Capoff_zps5f5c68cb.jpg]

Now for the inlet side. Three nuts and its off, note the size of the interior pipe as opposed to the outer pipe.
[Image: Exhaustinlet_zps06619f1d.jpg]

Peek-a-boo! Looks like the standard muffler works on the 'open chamber' theory, i.e. the space is sufficient to replicate open atmosphere.
[Image: Exhaustinlet002_zps9f91953f.jpg]

Let's have a closer look at this pipe.
[Image: Exhaustinlet004a_zps9e68c290.jpg]

Cutting it open reveals...
[Image: Exhaustinlet004_zps4bee30e0.jpg]

Can't wait to see the cross section of the muffler....
BATFINK (aka Tony)


GOD gave us a mind to use.........

Suzuki gives us a reason to loose it!!!!

Now you can change it to open outlets of original exhausts.
It's some work but it pays off.
I've already done it and I'm very content.Smitten
I own now open outlets of 50mm dia
This item has been on this site.
In your personal photos to drawings plus you can email me.
It's free.

I myself am waiting to make. A new heater
From 4 to 1 and then to two 50mm.

Good work mate, always what was inside the stock system.
Hi Fester, saw your thread somewhere, I am doing something similar but completely different at the same time.....

The choke ring at the outlet end of the intermediate pipe is held in place by two small weld runs. I assailed it with the 4” and it popped right out.

[Image: Exhaustinlet005_zpsf21c4b17.jpg]

Back to the muffler, in the image below you can see that the outer skin is folded over for some reason…..
[Image: AluminiumShell002_zpsecd67731.jpg]

Throw a stone grinding wheel into the 5” grinder and carefully take it back to the seam.
[Image: AluminiumShell003_zps421edb55.jpg]

Now to peel off the excess..
[Image: AluminiumShell004_zps24479020.jpg]

Hmmm, the outer aluminium shell is glued to the stainless core. Using a segment of a ‘box cutter’ blade, a small vice grips and a delicate hammer, I work my way around the perimeter of the seal.

[Image: AluminiumShell006_zps87d355a9.jpg]


Following up with some gentle box cutter work, I eventually break the seal.
[Image: AluminiumShell007_zps38a5a9a2.jpg]

Carefully I slide off the aluminium sleeve……
[Image: AluminiumShell008_zps4eb5325b.jpg]

The aluminium sleeve is a beautiful piece of work. Only 145 grams!
[Image: AluminiumShellcopy_zps617aff97.jpg]

Peeling the thin layer of insulation from the inner…
[Image: InnerInsulation001_zpsccff4e10.jpg]

Then a thin layer of stainless steel wool to reveal a sturdy stainless steel case…
[Image: InnerInsulation003_zpse03c366e.jpg]

I like your coriosity -

Can you do the same to a

Gen1 parr valve polution system
Garret turbo charger system
Roost type supercharger
Intercooler , air & water or both
Cheers thank, love ya work
Cutting through the welds to release the end cap.
[Image: InnerShell003_zps63b61784.jpg]

Removing pipe end and grinding away remaining welds to release the baffling;
[Image: Innershell006_zps29bd078c.jpg]

And here is the baffling, showing the path exhaust gases take to exit the muffler. Note the bell mouthing.
[Image: Guts_zps210519f4.jpg]

Inside of the end cap showing tack welds on the dress ring.
[Image: endcap004_zps1ecfa340.jpg]

Dress ring removed, leaving a neat 50mm hole…..
[Image: Endcap006_zps8116743e.jpg]


Is the modification obvious?

[Image: Widemouth_zps631c236a.jpg]

50mm is a sufficient diameter to handle all the exhaust gases. So what can I possibly use the other muffler for?

Use the other can as a storage stash tube, lockable
Water tight, Carry space, what volume is usable inside one
NOS bottle! Yee-ha!
If it's too loud....You're too old!
If it's too fast....You're too old!
If it's too sexy....You're ???
This is definitely the best "Exhaust thread" EVER! (so far)
[Image: PanBusa3sig.jpg] 
99 Hayabusa track bike
And the award goes to TempOzzy!

Problem is, the space within the spare muffler is way larger than my wee NOS bottle. Whatever shall I do?
Camel, you have inspired me to do a similar threat for the gen1 cans... but with the final objective to keep both cans (twin system) cut cut down by 20cm or so. Hopefully keeping all the original stamping clearly visable to fool the blueys. will also be polishing the machine lines out of them
BATFINK (aka Tony)


GOD gave us a mind to use.........

Suzuki gives us a reason to loose it!!!!

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