Working on the seat

When I first made the decision of eliminating the seat that came with my CB, I opted for using what I had in the garage -- that is, a spare KLR 250 seat.

Some people questioned my wisdom, while others were curious as to what it would look like.

I must admit that the thought of putting a dual-sport seat on a street bike sounds insane. Nevertheless, the curves worked out rather well, in my humble opinion, and the seat pan was paid for, so why not.

After chopping the seat pan to a single seat length and figuring out its basic position on the bike, I went ahead and molded the rear section. Once the rear section was fiberglassed and painted, I started with reassembly.

As you probably know from previous posts, I spent a lot of time working on the brakes, fixing the carburetors, and all the other stuff that makes the bike run, drive, and stop.

Well, while waiting for some brake piston seals, I decided to work on the seat itself. And here is where the challenges started.

When I first laid down the pan and molded the tail, I had the inner fender removed. It was no surprise that once I installed the inner fender in its place, that nothing fit the way it did before. Faced with the options of either not having the inner fender, or reworking the seat and tail, I decided against removing the inner fender. yes, I can be stubborn and this adds a ton more work. But, the thought of every piece of gravel and sand hitting the frame and battery, was the deciding factor.

So, the first step in this saga was to remove some more material off the seat pan. This went along smoothly (doesn't it always?). I then had to figure out how to attach the pan to the frame. At this point, I have the rear attachment brackets figured out and fabricated, but I still have to work on the front.

I started with some 1/4 inch aluminum flat bar

 Which I then bent in a vise to offset for the frame mount, drilled a hole for the mounting bolt, and rounded off the ends.

 Next, I found the proper mounting point on the seat pan, drilled a hole, and cut the end at an angle to accommodate the angle of the pan.

 And, voila, it worked.

It is attached to the seat pan via stainless steel carriage bolts, which will hide nicely underneath the seat foam. I still have to smooth all the edges and polish the brackets, but I'm one step closer to finishing the seat. 

UPDATE:

Tonight I finished making the front bracket. Actually, I used the "lip" method, where an aluminum lip slides underneath the gas tank mounting bracket, and holds the seat in place by friction. Since the seat is attached in the back by two bolted brackets, there is no way the seat will move. All the lip does is to hold the front of the seat in place, and to prevent it from rising.

First, I cut a piece of 1/4 inch aluminum plate to the desired length. Then, using a double-sided tape to temporarily hold it in place, I marked the location where the lip would attach to the seat pan. Since the seat rises up against the tank at an angle, I had to bend the lip to follow the contour of the pan. Once that was done and the desired amount of friction achieved, all I had to do was to drill two holes in the pan and the lip, and attach the two together with stainless steel carriage bolts. I then cut the excess bolt length to prevent it from snagging on the wiring that resides under the seat. To minimize frame scratching, I used a piece of protective door molding (self adhesive half-pipe used on car doors) on both the front of the lip, as well as the frame bracket.

Next, I'll be cutting the seat pan to copy the contours of the side panels, and carving the seat foam to the desired shape. And then it will be upholstery time.