Topic: Cafe seat mounting question

[sniper1]

I just received my Ducati 900ss replica seat from Airtech for my '75 CB550. I am looking for tips on a proper way to mount it to the frame. Also, I ordered a hoop from Lossa Engineering but it is too wide to mate up with the rear of the seat. Any thoughts on modifying the hoop to fit properly?

If you have any pics of how you mounted your seat or installed the hoop, it would be much appreciated.

Thanks in advance.

[KB02]

This is how I mounted the seat on cafe. Stole the idea from another board member (can't remember who) and modified it a little bit.

So I bought a fabulous seat on ebay (my attempts at making one did not come out well) and I have just been trying to figure out how to mount it. My whole thing was that I wanted to be able to maintain the stock hinge and locking mechanism for the seat. Most cafe seat aren't really designed with that in mind (unless you have a K6 or older and can get a Guillari seat). I saw this great post from shoemaniii - http://forums.sohc4.net/index.php?topic=64566.0, and I had my mounting idea!!! (Thanks again for the inspiration!!)

I started by getting some 3/4" ply and cutting out a piece to go under the seat:


As you can see in the above picture, there is a slight groove in the seat pan (for rigidity, I am assuming). Due to this, I had to cut out a section of the middle to allow for clearance. I started with a couple of holes, and cut out between them:




Then a slight angle to help fit the curve of the edge of the seat:


The radius of the edge of the seat was a bit more than I wanted to cut away for, so I needed a couple of shims to make up the difference.
Rough cut:

Refined:

In the second picture, you can see the cut to help clear the rear fender as well.

The hinges were simple hinges that I bought at the hardware store. I cut off the other end and just used these sides:


After carefully bending the hinges to make them fit right, I had to make sure they were placed correctly on the plywood:


Both hinges in place:


It's kind of hard to see in the pics below, easier above, but the lock itself stuck up father than I wanted it too, so I had to trim down the wood where that will mount by just a small bit. I locked the board on it's edge on my table saw and slowly raised the blade to make an indent. Reset the width of a blade and repeat. Came out quite nice, I think.




Came out rather nice, overall, and the latch and hinges still work just fine. I need to shift it just a touch to the right, and that will take just a touch of work to the rear hinge. After that I should be good to go.




It does sit quite a low as I had wanted it to - I like the lower edge of the tank to line up with the lower edge of the seat - but I think I will be able to get used to it. 

Then I cut out a base for the cushion from 1/2" ply and nailed the two pieces together. the back sits at a 100 degree angle to the lower section. Now I have to get some foam and I can start in on that.



That's what I was up to on my day off anyway. 

[sniper1]

KB02,

Thanks for the tip, I like your idea. Can you send me a picture of the hinge points you welded onto the frame? I'm interested in what you used, where you welded and how that interfaces better. I'm not sure about using wood (swelling from moisture, rotting, termites,,,,whatever, may cause issues later), but thinking that maybe some other type of material, 1/2" sheet of plastic or some other composite might work, and even be lighter than wood.

[KB02]

I used the stock seat hinges on the frame. I figured they were already there, so it made sense to use them.

If you look at the pic below, I just had to adjust the hieght of one of the hinges to match up with the hieght difference on the frame.