TOPIC:

Hey everyone, first off I'm new here. Currently I ride a 1980 Kawasaki KZ 550A1. It's my brother's bike that he has given to me for a few years to take care of, and ride. It was a bit of a beater/project for him so it's in a semi-rough state, but she runs great and we both love it.

Here's my question:
I've been looking for a while now for a sissy bar for her. My girl won't get on the back without one, and I want her to feel safe. I think I've found one that should fit a 1974-1978 KZ400, with measurements that I believe will mount to mine. What I can't figure out is where the brackets will mount to my frame after the main holes line up on my shocks. If anyone has any idea how I could get this sissy bar to bracket to my frame I'd greatly appreciate it, and so would my girlfriend. Thanks all!

The frame is missing a major support piece. Someone cutoff the rear plate that helps prevent the rear frame tubes from twisting under load. That little bridge piece is not really strong enough to do the job of the missing rear plate. The factory sissy bar mounts to the rear shock mounts and to the rear turn signal mounting tabs, which have dedicated screw holes for the sissy bar. If you want the sissy bar to really be safe, you should address the frame issue first, then while you're welding that, you can weld in tabs for the sissy bar's rear mounting points.

I saw a bit of the frame and the fender had been removed. Not sure why my brother did it, I'll ask him and rectify it. I do see a screw hole on the left side of the bike (if facing the rear) on the blinker tab, however on the right it doesn't have one. The strange thing is, the right doesn't appear to have been cut in any way, so I wonder why one side has a screw hole, and the other does not. You should be able to see all this in those photos.

Either way, looks like it's to the welder. Thanks very much!

Edit: I attached an image of a KZ550 frame. As you can see, one side has a blinker hole and one does not. Just seems weird.

Left and Right are as you are sitting on the bike.
The cylinders are numbered 1-2-3-4 left-to-right sitting on the bike, as are the exhaust pipes, spark plugs, carburetors, etc

The frame was hacked to make it into a bobber/chopper or cafe racer or something.
The left side has a frame grip, hence the bolt-hole in the tab. Not sure if the right side should have it.
eebbaayy photos. Partzilla diagrams or PowerSportsWarehouse.

Taking a Passenger: Personally, I don't recommend it. If you're a new rider, don't. Accidents happen. Make sure she wears a good full face helmet, leather/armored jacket, leather gloves, boots & at least good blue jeans (which still can get shredded).

Good advice Martin. I never take a passenger unless it's their idea and they really want to do it.

Also, Martin is correct. The early type Kz550A frames appear to only have had the single, left side grab handle, so only the left turn signal tab had the screw. The later frames had the full grab rail, which required both turn signal tabs to have the screw hole. The later frames can be identified by the passenger peg mounts. Later frames had bolt-on, cast-aluminum triangles, but early frames had welded-tube triangles. There may have been some overlap on grab handles and aluminum triangles, but I'm not sure how much.

...Really wish I could get to the original Kaw parts fiche pages to scrape a copy of it. It would make it easier to get definitive answers on these things. I know they exist on partzilla, etc, but it's not quite as condensed, thus much more difficult to scrape images and text.

Ahhh, I see. I didn't consider a frame change on the same model. Looks like I'll have to weld at least one tab for a proper sissy bar mount. Also, with regards to a passenger:
She loves to ride on it with me, just doesn't like the feeling of having no back support (I don't blame her.) We never go far distances, nor on the highway as we live in a relatively small town. As always I'm very careful, and she will always be wearing gear like myself.
Thanks for all the help guys.