Contributed by John Ditmore

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First things first: You’ll need some tools and supplies. The first thing is some nice high-density, closed cell foam. I used ½” thick pieces. Turns out you can get just what you need at REI. They have a “sit pad” which is a 2’ sq. of foam ½” thick. Perfect. I got two pads at $5 ea. As far as tools go, you need some things to cut and shape the foam. I discovered there are a variety of ways to cut and shape foam. Each way has its pros and cons. Here’s what I used:

Hacksaw, small serrated knife, scissors, Dremmel tool with a grinding wheel. You’ll also need some needle nose pliers to remove the staples from the underside of the seat, a staple gun to re-attach the cover and some spray on stencil glue to hold the new foam pieces in place when replacing the cover.

This job will take no more than 2 hours, and probably less. I say 2 hours since you’ll need some time to test the seat and rework if needed.

The concept: The idea here is that you are going to remove a section of the stock seat foam and replace it with the more comfortable stuff. At the same time you will be changing the angle of the saddle area to reduce nad crunch into the tank. Also this technique creates a wider, flatter saddle area. Keep in mind what you don’t like about your current seat and take this opportunity to create your own customization. What works for a skinny, narrow behind person such as myself may not be comfortable to someone of a different stature. An example of that is my seat mod proved too wide for a friend when I loaned it to her for a day.

Also, don’t go hogging out a bunch of seat foam all out once. Start small. Take a little off, add some new foam and then see how you like it. You can always remove more as needed, but it’s a lot harder to build up if you take too much off. 

Step 1.

Remove the seat and carefully pull out the staples holding the cover to the bottom of the seat. Just remove enough to expose the driver half of the seat (unless your planning to rework the passenger side as well). Be careful not to tear the fabric.

Step 2. Pull the seat fabric back so that the driver’s portion of the foam is fully exposed.

Step 3. Mark the seat where you will be doing the cuts. This will give you a general guide to help keep the cuts uniform and even. I decided to add two ½” layers, so I made my marks roughly 1” deep. Don’t worry if you don’t mark it deep enough the first time. You can always remove more foam later.  

Step 4. Time to cut. I originally started out with the Dremmel, using a small thin cutting wheel. That proved too slow. I wound up using a hacksaw to make big sweeping cuts by hand. That works well to keep everything even. Then I used a small, serrated knife to trim further. My goal was to change the slope so that I had less of a forward lean, as well as widen the rear portion to increase the surface area where your butt goes.

I also found that by re-mounting the hacksaw blade so that it is 90 deg from original allowed for a nice even cut lengthwise.

Step 5. Now it’s time to cut and shape the replacement foam. Instead of being all scientific and engineering a drawing to cut from, I just laid the sheet of foam over the cut- away and marked it roughly where I thought it should go.

Then I used scissors to cut the foam to the desired shape. Once I had a shape that fit snugly into the cutaway, I used that piece as a template to cut the second one (I added 2 layers of foam). I also cut the foam about a ½” wider than the cut away on either side, since my goal was to widen the saddle area. Since the new sheet of foam will then be sticking out, you need to make some side bolsters to accommodate that.

Step 6. Make the side bolsters. These will support the sections of new foam that hang over the edge. Again I used the eyeball method and just lined up a chunk of foam and marked it where I thought it should go. I started with the triangle section that was cut away to make the saddle piece.

Once the first bolster was cut to rough shape, I used it as a template for the second.

Step 6. Glue and shape the bolsters. Now comes the sticky part. Spray the stencil glue on the bolsters and the on seat where they’re going to attach. The cool thing about stencil glue is that it forms a tacky seal, but also allows you to remove and re-position the piece very easily. Once the bolsters are in place, you can use the Dremmel with a grinding wheel to create the desired transitional shape. Be careful with the Dremmel, use light strokes. It may help to practice on some scrap first to get the hang of it since it’s real easy to have the wheel just gouge the foam.

Step 7. Attach the saddle sections. Use the stencil glue again. Add the two layers into the cut away pocket.

Use the Dremmel again to smooth and shape the joint between the bolsters and the saddle area.

When done it should look something like this:

Step 7. Replace the cover. This is simply a matter of stretching the cover back over the seat and re-stapling it to the seat form. ¼” divergent point staples work the best.

The thing about the cover is make sure you pull it tight as each staple is put in to smooth out the wrinkles and stuff. The cool thing is despite the rough looking nature of the foam before replacing the cover, it looks pretty smooth once covered.

Step 8. Test ride! This is important. If you don’t like it, simply repeat until you do. In my case I found that I had not removed enough stock foam from the rear section of the saddle area. So I removed the cover and cut out more foam. Also, you may want to keep it narrow, so just cut the saddle area to fit with out bolsters.

Long term update: I really liked it once I got the saddle angle figured out. A 200 mile ride confirmed the comfort was real. But I wanted to go one step further. So I ordered some sheets of ½” thick NASA memory foam. This is the stuff used on the Shuttle seats. So once I got the foam, I removed the cover, cut even deeper (this time the hard plastic of the seat core was showing at the very back end of the saddle cutout) and added two layers of the cushy memory foam on top of the blue stuff. I highly recommend this stuff. It’s very cushy and therefore must be on a base of the firmer stuff to work properly. You can order the foam online here: http://www.foamorder.com. It was around 15 bucks for 2, 2’ squares ½” thick, including shipping.

Lesson learned: A comfy seat can be had for a fraction of what Corbin charges, if you’re willing to do a little work. Good luck!

JD