Modify frame to accommodate mufflers

The headers/mufflers on my '82 kz440D are rotting out, so I have been in search of replacement options. I happened to come across a set of stock kz440A pipes, which I initially was pretty excited about. Sadly, the left pipe doesn't fit the bike. I think that because the pipes were made for a kz440A , the left muffler had a bit narrower of an an angle coming off the header, as the chain drive didn't require as much clearance (the kz440D has a drivebelt). That's my guess, anyway. The pipes look identical from every angle.

I'm wondering if I can use a torch to heat up the frame tubes where the passenger footpeg mounts (see picture) and use a pry bend it outward to give the muffler more clearance from where it gets hung up on the axle bolt. I don't have a lot fabrication/modification experience, but it seems like a long shot. The frame tubes there are about 3/4" in diameter. I'd probably have to remove a bunch of shit to safely heat it.

Another potential option is to grind down the inside of the passenger footpeg mount. Taking off a 1/4" might give me the clearance I need, but I have doubts about the safety of such a modification.

Given how sketchy those strategies sound, I'm debating whether I should take an entirely different approach and return the stock pipes and figure out someway to replace the rotted crossover and mount aftermarket mufflers.

Any input will be appreciated. Thanks.

The parts fiches for the 440's are not the greatest, but when I look it up, the Kz440D and Kz440A list the same part number for the main pipe-muffler assemblies.

18001-1496 for the left side.
18001-1248 for the right side.

I had to look at a few fiches for 1982 and 1983 but they specify multiple models using the same fiche. D2, D3, D4, and D5 use the same and A2, A3, and A4.

Maybe the difference is a bracket or connector pipe?

PDF for 1983 D4
www.kawasaki.com/Parts/DownloadDiagramPd...3&modelcode=KZ440-D4

Page for 1982 A3
www.kawasaki.com/Parts/PartsDiagram/135296/1982/KZ440-A3

There is some goofiness in the fiches, though, because look at the numbers on this page.
They should be the same as the PDF above, but they are not.
www.kawasaki.com/Parts/PartsDiagram/135192/1981/KZ440-D2

LandLeftBehind wrote: The headers/mufflers on my '82 kz440D are rotting out, so I have been in search of replacement options. I happened to come across a set of stock kz440A pipes, which I initially was pretty excited about. Sadly, the left pipe doesn't fit the bike. I think that because the pipes were made for a kz440A , the left muffler had a bit narrower of an an angle coming off the header, as the chain drive didn't require as much clearance (the kz440D has a drivebelt). That's my guess, anyway. The pipes look identical from every angle.

I'm wondering if I can use a torch to heat up the frame tubes where the passenger footpeg mounts (see picture) and use a pry bend it outward to give the muffler more clearance from where it gets hung up on the axle bolt. I don't have a lot fabrication/modification experience, but it seems like a long shot. The frame tubes there are about 3/4" in diameter. I'd probably have to remove a bunch of shit to safely heat it.

Another potential option is to grind down the inside of the passenger footpeg mount. Taking off a 1/4" might give me the clearance I need, but I have doubts about the safety of such a modification.

Given how sketchy those strategies sound, I'm debating whether I should take an entirely different approach and return the stock pipes and figure out someway to replace the rotted crossover and mount aftermarket mufflers.

Any input will be appreciated. Thanks.

Why is it upside down?
Steve

I, too, looked at the fiches prior to making the order. There are some slight differences between the pipes now that I have them. The crossover is different. The kz440D has a smaller diameter pipe which expands on either side to a "female" fitting, whereas the new pipes have a large diameter pipe that has a "male" fitting. Despite the differences in the crossover, it doesn't appear to be getting hung up there. The left muffler collides with the axle bolt on the rear wheel, on the same side as the belt pulley. The right muffler fits OK.

Also, there is a threaded hole in the bottom of one of the headers (left I think) of the new pipes right where it bends under the bike. I have no idea why its there.

@SWest - What is upside down? The footpeg? Its just hanging there because I took off the original mufflers.

I'll take some more pictures as soon as I get a chance!

The KZ440A is a LTD model with chain drive. The KZ440D is a LTD model with a belt drive.
I have worked on both, they have the same engine and the same frame.
Looking at the pictures in the factory service manual I can not see any difference in the frames.
Something is wrong with your exhaust if the frame is undamaged.


.

Instead of bending the frame, can you dent the pipes or mufflers with a hammer, denting them in where they are making contact.

Before damaging the frame or getting out the BFH and ruining the exhaust. I’d suggest a little research to determine if the exhaust you purchased is indeed correct for your bike.

Loudhvx and Nebr_Rex both are very experienced builders, heed there suggestions.

The consensus seems to be that the kz440A mufflers should fit a kz440D frame. I hope that I'm just doing something stupid here. Im going to take another look after work today, and take several pictures so you all have more to work with here.

I should mention that I brought the bike down a year or so ago from a stopped position (oil got under the rear tire and I lost traction as I pulled off) and skidded halfway across the road. I had a fleeting suspicion that maybe the muffler mount was bent inward from that, but it seems really unlikely as the foot peg and muffler were not significantly damaged.

I would snug up the passenger peg and set both out, as if to be used, and look down from above and see if they make a straight line or are at least symmetrical with each other. If not, then it could be something is bent. I would also sight it from the rear using the center stand if possible and see if one peg is bent up or down.

So I took another really good look at the mufflers and found no visible differences. I found that I can get the left muffler into place with few good thuds, but it sits on the swing arm (pictures 1 and 2). So obviously that won't fly.

I like the suggestion of looking at the footpegs from behind to get a sense of whether the frame mounts are bent. The mounts differ in their distance from the swing arm on either side (pictures 3 and 4, left and right sides). The left side frame mount sits about a 1/4 inch closer to the swing arm than the other side.

Maybe bending the frame mount outwards is the solution after all? If so, it seems like the only way to do will involve taking off the belt so I can torch the frame and use a pry on it. My ears are open to any other suggestions.

How much do you think the footpeg mount would have to move out?

(I can't see the photos, maybe I can see them when I get home.)

loudhvx wrote: How much do you think the footpeg mount would have to move out?

(I can't see the photos, maybe I can see them when I get home.)

I think about a 1/4 inch.