I've spent the last couple days hacking up my stock DL1000 seat, and upgraded the foam with Sunmate and Pudgee. The inspiration for this project came from this great thread: http://11109.rapidforum.com/topic=109076102602
and I want to give full credit in advance to my techniques to this author.
I'm not going to go into as much detail as the post above since you can read there if you want more details.
The plan was acomplish three things: 1) Replace the existing stock foam with high quality foam for a more comfortable ride, 2) Lower the seat, and 3) To be able to reuse the stock seat cover after I'm done.
Here is the stock DL seat, which hurts most people's butts after an hour:
My first task (after removing the cover) was to mark out the lines to guide me during cutting. My goal was to lower the seat height by 5/8 of an inch. To do this, I used a level (bike on center stand) across the seat in several locations, and then marked 5/8" below the level. Then filled in the lines. The side marks are to remove the extra padding so it's easier to reach the ground with my legs:
Another view from the side. Notice that the mark on the back part is only about 1/2" and less towards the back. There's less foam there. Lowering BOTH the front and back rider area the same amount (or close) is critical in order to reuse the stock cover!:
Beginning to cut. The electric kitchen knife works well. Since the blade does not reach all the way across you have to be carefull to not let the end of the blade dig in too much during "blind" cuts. You can always fix that later! It's important to constantly watch the near line and far line (back and forth) while cutting, otherwise you will find yourself cutting too far into the foam:
Here we have the rough cutting done. There's a LOT of work to go
Another shot of the rough cut. Don't over do it, you will have time to tweak later after the new foam is installed:
Now mark the cutout lines on the bottom. The pattern leaves the supporting sections in tact:
I have now cut up through the foam to make holes in the seat, and marked lines 1" from the bottom since the foam I'm using is 1" Sunmate Med-Firm foam. This line is used later for the second layer:
Here I have cutout the Sunmate foam and glued them into the holes with 3M foam glue, and put weights on since the bottom of the seat tray is arced. 3M foam glue is better the contact cement because you have time (30 seconds) to mess with it:
Here's another look with the first 1" pads in place:
Next I have marked lines to make for a larger second layer of Sunmate foam. I use the razor tool shown to help cut out the bottom area, and use the electric knife to make most of the top cuts:
Cutout in the front is done. No cutout (larger area) needed for the back:
Here I have glued in the 2nd layer of 1" Sunmate foam in the front and the back. The back sticks up beyond the seat and will be trimmed later. Notice how much Sunmate I have left over to redo my office chair! And if I'm carefull I'll be able to have enough of the Pudgee (greenish foam) to do the top layers:
Now I will use contact cement to glue down the foam edges on the bottom. See the yellowish glue in a couple places. Contact cements is best here becuase it sticks instantly so I don't have to hold the foam down:
Now I have installed the top layer of Pudgee foam. This foam is the best top layer. It's .5" foam. Notice how I have done this: In order to keep the new height of the seat (5/8" lower), have cut down into the seat all the way across to a level of 5/8". This is because the Pudgee foam is .5" and I want to be able to trim the stock foam down to meet the Pudgee:
Here's a side angle of the Pudgee top layer. The contour of the foam is exactly like stock (except 5/8" lower) so that the stock cover will fit later. The rest is still rough sanded, and is a little higher then the Pudgee so I can sand it down to the level of the Pudgee:
Next comes the final sanding. The belt sander (80 grit paper) is a BIG help in making things flat and nice quickly. Then the little sander is good for fine tuning. Be very carefull with the belt sander! You have be constantly aware of where the sander edges are or you are going rip a big gouge in the foam and/or strip the paint off of your side plastics!
The belt sander makes pefectly flat lines quickly. Especially usefull below the Pudgee which I didn't show. Here the sanding is DONE.
Whew, it took a lot of carefull sanding with both tools, cutting with the knife and hand sanding is some areas. Note, you can't really sand the Pudgee so don't even try. Instead use your electric knife to cut it. Pudge is too rubbery to sand:
Another side view of the finished seat. Looks like the stock seat doesn't it?:
Now it's time to hope that the stock cover still fits.
For this you need three things to do the best job: 1) A heavy duty stapler with 3/8" staples (not 1/4" like in the stock seat), 2) A bunch of sping clamps, 3) a hair dryer.
1/4" staples don't work. They are too short and will drive you crazy if you try to use them. Instead use 3/8". You can get the clamps at Home Depot for $10 for about 15 of them in a bag. Use ones with a larger flat contact area instead of older metal clamps, so the metal edges don't dig into the cover. You need a lot of clamps so that you clamp down the cover (using the hair dryer to warm the cover), so that you can adjust the cover with no wrinkles before stapling.
Once all the clamps are on (sorry no pic), start stapling and removing the clamps as you go. If everything goes well your seat should look like this:
There are a few imperfections here and there that you can feel if you run your hand over some areas, but they are hard to see unless the light is just right.
I am VERY happy with how this project turned out. It took about 12 to 15 hours (on and off) to complete but was a lot of fun. Sitting on the seat it feels a lot more comfortable and I can almost get my feet flat-footed on the ground now. Big improvement.
Hopefully tomorrow I can ride if the weather doesn't suck like it did today. If so I'll write a little update on how the seat feels. But I'm pretty sure my butt will love it.