Mystery exhaust ID: what did I find in my attic?

My current house has an oversized "detached" garage close to the house with a covered breezeway between. The little roof above the breezeway is a crawlspace between the two and carries electrical conduit. I bought the place in early 2003 and hadn't yet felt the need to crawl up there into the cobwebs and dust.

Last week I was storing some of my bulky, lightweight spare car parts in the rafters of the garage when something shiny caught my eye. Long story short, there was a used aftermarket 4-cylinder bike exhaust left behind in the crawlspace, and I have no idea what kind of bike it is for. Help?

It is a 4-2-1 Sudco...I have lost touch with the folks who used to live here, but I am guessing it has to be a pre-2002 bike, and likely a bit older because it was ridden, removed, and put into storage by early 2003. It is used, but not in terrible shape. Here is the brushed aluminum can:

Here you can see the construction, slip joints, exit low on the right side, no hangers or braces apparent.

And here is the flange arrangement, which seems like the most logical place to start narrowing it down:

The flange is for M8 studs, and the slots fit studs 2.2"-2.55" (56mm-65mm) apart, so the head probably uses 60mm stud spacing. Note the angles, opposite on pairs of cylinders. Viewed as above, between the exhuast port centers are as follows, left to right:

99mm or 3.9", 114mm or 4.5", 96mm-3.75" I am guessing that number one or number four was bent or warped a bit, and both the outside measurements are supposed to be the same.

The primaries have a 34mm/1.31" ID (38mm/1.5" OD) which would seem to imply a bigger four, but as a car guy, I don't know the first thing about bike tuning. It is stepped to a 45mm/1.75" OD secondary, and a 52mm/2.125" OD collector.

Any Japanese sportbike experts care to venture a guess, or at least help me narrow down engine families by exhaust stud arrangement, so I can figure out what to do with this thing?

Thanks in advance!

The stud pattern is common, if not standard. The large pipe suggests something 750cc+, likely 1000cc range. The style, with the low slung muffler, suggests a standard or sport touring.

I wouldn't really call that narrowed down though.

Their current catalog lists similar exhaust systems for only a few bikes: http://www.Sudco.com/vol33/5.pdf That's not to say they didn't offer other systems in the past. You could poke around their website to see if you can find anything else. http://www.Sudco.com

Sudco ap chart circa '06

http://www.sudco.com/pipe_app.html

I'd guess FZ1 if I had to pic from that list.

Thanks for the ideas. I had poked around a bit on the Sudco site and didn't really find any definative info.

As far as the stud pattern, I've seen lots of Japanese bikes with similar setups, but with all four cylinders on the same diagonal slant instead of pairs of two and two, so I was hoping that might help narrow it down.

I guess in a worst case scenario, I can throw it up on Craigslist as a mystery 4-cyl. motorcycle exhaust and see if I get anyone intetersted.

Cinderella on 2 wheels.

Nice story.

Make the royalty check payable to M-i-c-k-e-y...

The 1 and 2, 3 and 4 collectors together is kinda strange, isn't it? I though you're not supposed to do it that way. Either 1 and 3, 2 and 4 or all 4 into 1. Anyway, the rest of it looks like Locost muffler to me.

depends on the firing order. You should see the berkeleyed up headers on my katana. They connect at random places. Y joints and H joints and all sorts of nonsense.

My guess is 12 and 34 into 2 then into 4 would give a little more torque than 4 into 1. All the more reason to think its off a nudey like the fz.