DIY seat: lessons learned

[dingophil]

(1 of 2) For the past few weeks, I have been toiling away trying to rebuild or fix the standard driver seat, which we're all aware has issues. Mine are that the part your butt actually rests on is maybe 1/2 inch thick, allowing pressure points over time. The other is my inner thighs rubbing the outer portions of the seat cushion. So I set out to make a more comfortable seat, and having watched tons of YouTube videos, began my quest. It did not go well...

I purchased a few items to begin, trying to keep costs below $75 US:

- 3" x 3' x 3' high density foam, foam glue, marine-grade vinyl (ostrich!!), and a 1/4" x 2' x 2' square of memory foam. 

I first removed the staples around the under side of the seat, stopping only to wonder what I should do about the piece that locks the seat to the bike. Since there were staples tucked under it.

I snapped the bolt. Must have been some loctite in there or something. No matter, I replaced it with a quick trip to home depot, and $2.07 later I had one 1/4 bolt, a locking nut and a washer.

Next, I traced the seat pan onto the foam leaving extra space at the edge and cut the foam with a bread knife, because I was too cheap to buy an electric knife. Mistake! It took forever and the edges were very ragged. Also, it's extremely imprecise, so fine-tuning your shape is nearly impossible.

Once cut, I glued the single layer onto the pan (above). Mistake! Don't glue anything to the pan unless you're 150% sure it won't need to come off. If you decide to use high density foam, do not use a single layer that goes from the rear to the front of the pan. Use one layer from the rear to the bottom of the "seat horn" (quasi-saddle term), then glue more layers to build up to the height of the front of the pan.

The thing looked awful but if I could make it comfortable, and cover it over, I don't really care.

So the single layer wasn't working out. I could feel every single groove in the seat pan through the foam. It was worse than before, was sitting me up higher, and forcing me farther forward!!!! 

I purchased a wire cutter for my drill, as I have no need other than this project for a rotary cutter of any sort. Mistake!! While I could use it to shape the foam, it was unwieldy (read: if you're not careful, you'll catch a finger), untidy, and imprecise.

 

[dingophil]

2/2

Wire cutter and aftermath:

Horrible seat. I gave up. I cut the foam out of the pan, used the wire cutter to clean up, and went back to the drawing board.

Finally, I decided that I need professional help, lol. But I'm stubborn, so I glued the memory foam onto the factory injected foam and closed her back up!

There is definitely tiny bit more give and I'm glad for the memory foam. But if I had to do it all over again, I'd take the sore spots and save up for a proper after market seat.

Thanks for sticking till the end. I hope it was more enjoyable for you guys than "fixing" the seat was for me.

[BBB]

Thanks for sharing your experiences @dingophil. They just reinforce to me why I didn’t attempt this. I gave mine to a local boat upholstery firm and they put a wide, deep gel section in for me, just where your sit-bones are. Unfortunately this had been one of my winter tasks and I haven’t had the chance to put any decent mileage on it yet.

[koth442]

Thanks for sharing, hopefully someone thinking of heading down the same path will learn something from your experience.

[scaley]

a coarse sanding disk is best for shaping the foam. Creates a right mess though so use all the safety gear and cover anything you don't want knee deep in foam dust.  I narrowed my FJR seat. After getting the shape right I covered the whole seat with a sheet of thin foam stuck down with spray on contact adhesive.

[Fyvone]

Yes thanks for the insight. I have been contemplating the same project. Definitely having second thoughts!

[nicksta43]

I added a layer of 3/8" rebond foam. (Carpet pad) in between the seat pan and the original foam. The factory cover had plenty of stretch to go back over. Completely eliminated any complaints I had and you'd have to have a stock one sitting right beside it to really tell. It does sit you up a little higher but I've got long legs so it's not an issue for me.

 

Edit to add a picture.

Edited April 16, 2019 by nicksta43

[sirepair]

Sometimes, no matter our intentions or efforts, things just don't work out!

I'm impressed that you tried this, and that you shared.  I have dabbled in upholstery myself and know how challenging it is.   

I lucked out and bought a slightly used Russell Day Long that is working pretty well for me. Not perfect, but so much better than stock.

[sdwillie]

I give you props for trying. If I did it myself the seat would end up looking like the wheel of The Flintstones car.

[Kned]

Late to the party, but here's a description of what I did. I have the Yamaha comfort seat, which was better than the stock seat, but I've still had some serious issues with my tail bone going numb/sore/painful after an hour or two. I've considered different ways to solve this, but finally went for the DIY approach. It worked wonders, and I can now ride 6-7 hours before I have any kind of discomfort in the tailbone. It took me about an hour, and hardly any expences.

Please note that following the instructions below will be a chance to take, it may not work for you, and you will off course ruin any warranty on the seat. I take no responsibility whatsoever for anything ever under any circumstance. That said, I'm very happy with the results I got.

Here's what I did, the idea is to create a void space under your tailbone:

See photos: https://imgur.com/a/C2GQrl2

1: Remove the staples in the aft part of the seat, and pull away the cover and a layer of plastic to reveal the foam inside. Be careful not to damage the cover or plastic!

2: Remove the screw that you find under the foam. Grind the head of the screw a little more flat, and use epoxy glue or similar to round of the screw. See photo.

3: File or sand away the edge on the rear part of the plastic seat pan. See photo. You want to remove the edge completely in a 10-15 cm wide area.

4: Using a sharp knife, remove the yellow foam in an area that's approximately 5 cm wide and 3-4 cm long. Chamfer the edges, you don't want any vertical transitions, they will feel like an edge.

5: Re-install the screw and glue it to the plastic seat pan.

6: Put the remaining foam, plastic and seat cover back in place. Stretch the cover material into place and staple it back on. Use 6 mm staples. My staple gun was not powerful enough, so the staples went about halfway in. I used a hammer to make them go all the way.

[maximo]

Parallel story and lesson:  My 20 yr old SV 650 stock saddle fit me perfectly from the get go. After 80k miles it had shaped in a way that no other saddle had ever shaped, which is to say it molded exactly to my needs.  The vinyl recently ripped, so I took it to an upholsterer to have it recovered. When I picked it up, the guy, very proudly, told me that he noticed the old foam was stiff and misshapen, so he took it upon himself to cut off the top layer and glue a different, softer layer on top before re-covering it.  He was beaming as he told me that his cruiser customers love that foam.

It completely ruined the saddle. Now I sink into it and within 30 minutes I lose sensation in my legs.  

The upholsterer figured that one kind of happy customer would make every customer happy, without understanding that not all bike ergos are the same.  

Lesson learned: only let saddlemakers touch your saddle. Use folks that know what they're doing. 

[DavidS]

Years ago, I had a boat that needed the back bench seat replaced. I figured "How hard can it be" and quickly learned I had no clue what I was doing. After a weekend of frustration, I took the boat to a qualified upholstery shop and had them fix my sorry attempt. Cost me a little extra since I started it on my own, but I was just happy to be done with the project.