Help ID 4/2 exhause, please.

Came to us in a parts lot from a local bike shop that focused mostly on Kawasaki in the day.  Seller / owner retiring & liquidating the shop for health reasons.  He's pretty sure it's a Bassani circa early-mid '80's that fits a KZ550.

Looks like it's never been run.  Very minor surface rust on inside of pipes.  Shelf wear / minor scratching in the black finish.  No dents.  No hardware.  No markings / #'s / or anything that could ID it, just blank metal.  Fine welds. What appears to be a sidestand stop on the left side connector pipe.  No mufflers came with.











Center-to-center of 1/2 and 3/4 headpipes is ~88mm -  ~3 1/4in.
OD of headpipe collars is. 40mm
OD of collector(s) out is 48mm.
OD of connector pipes is 48mm.

This is too nice a system to scrap. First reasonable offer plus CONUS shipping.  It's going to Mid-Ohio if it doesn't sell before.

Thanks all.

Good Ridin'
slmjim & Z1BEBE

1-4 & 3-4 center to center distance is 3.25" on the 650/750.  1-4 center to center distance is 290mm.

I wonder if those pipes are for these bigger bikes?

I have a NOS Supertrap header, with two different mufflers (canister and megaphone).  Thing is, though, I'm quite a picky type, and I don't like headers that hang low under the sump, like these pipes.  I suppose I need to just sell them, because I'm not going to use them.  If I could find a set of headers, maybe these, that tuck tight under the engine, I'd get on the custom exhaust path again.

I just built a similar 4 into 2 for a Z1 engine in a 650 frame.

1 to 4 (2 to 3) C-C is 3-3/4" on a Z1 head, so for sure they are built for a small engine bike. The crossover pipe looks to be quite large.

Outer ports on a 650/750 are 3-1/4" C-C, inner ports are 5" C-C. I doubt they are for 550, I believe 550 has different port spacing than 650/750 as the heads on those are quite narrow.

 

We didn't list 2-3 and 1-4 spacing because the crossover pipe's slip joint makes those dimensions somewhat variable.

Could someone please respond with the exhaust port OD of a 550 head?  Looking for the OD of where the exhaust gasket is inserted, not the port itself.  Might help by process of elimination if the collars on this pipe are too large for a 550.

Thanks for the responses everyone!

Good Ridin'
slmjim & Z1BEBE

I don't have a 550 head, but the exhaust port ID on a 650 is 1.50" and a Z1 is 1.62" diameter.

Looking at those pictures the sleeves where they attach to the exhaust ports are huge compared to the down pipe size - quite odd.

My Supertrapp header has 39.5mm OD flanges where they go into the head.  What size are these?

The OD of the retaining collars is nominal 40mm. 

The headpipes taper to ~30mm ID about 1 1/2 inch in from the inlet.

Good Ridin'
slmjim & Z1BEBE

So, must be a 650/750 header.  

There is a gasket on Amazon which is "supposed to be" a replacement for the 550 gasket 11009-1866 which is 39mm OD

" Curiouser and curiouser! "
--- Alice --- (in Wonderland)

Good Ridin'
slmjim & Z1BEBE

I've been meaning to pull the ancient 4-into-1 off the '81 GPz550. Let me see if that can happen this weekend; if so, I can get some measurements.

MODS - just realized that slmjim posted the wrong OD of the retaining collars in the OP as 50mm. Oops...

They are 40mm.

Please correct or, enable edit & we will do so early AM tomorrow.

Thx.

Good Ridin'
slmjim & Z1BEBE