"Floating" seat

[billyp]

Since I had the idea to build a bike with a horizontally mounted shock, I always had another idea to show the shock and all the suspension work by doing a floating seat. I needed to have the shock as close the the seat as possible to get enough room over the tire for travel, so the idea wasn't only for looks, it was also for function. I went through a lot of different ideas and designs and did a lot of research on composites and foam core build ups. I got most of my ideas and techniques from carbon fiber kiteboards and how they're built, using carbon fiber with some sort of foam core in the middle. I don't know if any of you have ever seen some of the things these kiteboards can do, but after watching some videos on youtube and seeing the beatings they take, I figured that was a good way to construct my seat.

The layup for the seat was as follows

2 layers of 5.8oz 2x2 twill
2 layers of 6.6 unidirectional carbon
1/4 inch Divinycell H100 foam core
2 more layers of uni
2 more of twill

Everything ready to go

Sheet of glass sprayed with Frekote release spray

First 4 layers

Divinycell

Epoxied in some aluminum pieces where the mounting bolts will go

Last 4 layers on top, then into the vacuum bag

 

[billyp]

Added some mounting brackets to the frame, also act as gussets to help strengthen the rear subframe

Popped the seat off the glass and let it cure for a couple of days. Looking at it, I guess its more of a seat support as the actual seat and seat pan will attach to it.

Gave it a rough trim and set in on the frame with 1/4 inch spacers

For those thinking "is it strong enough??!!"

I'm 6' 3" and weigh 225

The actual seat pan that goes to the upholsterer will be sheet metal but it will sit in a carbon fiber base that I'll be working on next

 

[tiretread]

That looks pretty stout!

 

[jpmobius]

Very nice. Hope you will elaborate on the steel seat base which seems a curious choice considering your nicely engineered composite under structure. Do you have the shock linkage sorted out? I thought you were having some issues with the kinematics.

 

[billyp]

I meant the actual seat pan that will be upholstered will be steel. I'm going to be making another carbon piece that the pan will sit in then all will bolt together. Sounds confusing but it works in my head.

Everything is engineered and figured just need to get it done. Taking the summer off from building to enjoy some family time on the lake and build a shed/workshop so progress will be nil for a few months