ABS Seat Pan

[MisterCinders]

I am intrigued by this seat/seat pan assembly.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=190463390662&ssPageName=ADME:X:eRTM:MOTORS:1123

Anyone have any experience with the ABS material? That integrated CatEye light is pretty sexy.

[spyug]

Most body parts on bikes are now vacuum formed ABS in the 5 or 6mm thickness ( which this also appears to be). By itself it is fine for non stressed parts but for something like a seat pan it would need to be reinforced. I'd be concerned about that.

ABS will crack if stressed (just look at some of the 'dropped" crotch rockets) and depending on the quality and thickness can shatter with extreme cold.

It is a nice looking seat but you really need to know that it is strong enough to support you. Personally, I think I'd prefer something in fiberglass as its likely to be sturdier.

Find out more before you dive in.

Good luck.
Spyug

[MisterCinders]

Thanks for the tip.

I would probably craft a panel from treated plywood to reinforce the bottom and provide a better attachment platform to connect to the frame.

Will look harder at fiberglass also.

[tkent02]

That's a cool seat.

[salty_monk]

Says you are meant to mount it to your existing seat pan so that is where the additional strength required would come from.....

[Guest]

Thanks for the tip.

I would probably craft a panel from treated plywood to reinforce the bottom and provide a better attachment platform to connect to the frame.

.

Just reinforce it with a few coats of fiberglass.
The seat I have on my bike is fiberglass but I still put a few thick coats on the underside.
I also made brackets and rubber legs from the original pan to rest on the frame like the factory pan.

Also keep in mind if you buy a seat thats already finished you'll be kinda limited as to any mods. No trimming or whatnot.

[Guest]

Says you are meant to mount it to your existing seat pan so that is where the additional strength required would come from.....

That would never work..

[MisterCinders]

That would never work..

Yeah, I asked the vendor about attachment, and he agreed that an existing seat pan would not work out.

He suggested marine plywood (like a lot of GSers have done) or some kind of HDPE cutting board material (also sold as Starboard at marine supply stores). I would probably shape a panel of 1/2" treated plywood. I have used HDPE for other stuff (it's great for a router plate or router table insert), but don't know that I'd use it for this.

As for fiberglass, I know two things about working with that material: (1) Jack; and (2) S**t.

[MisterCinders]

Necroing this thread - I got the seat installed.



It took a bit more work than I anticipated.

The space underneath the seat mold was thicker than a sheet of plywood. So I used a piece of treated 2x12 and shaped it to fit underneath. Without a bandsaw, shaping took a lot of planing by hand. That will make a man out of you, lemme tell ya.

Attached the old seat hinges to the board, and screwed the seat to the board, so the entire thing swings up/down like the old seat.

Problem - the new seat did not rest squarely on the frame, and the original frame jutted out too far. Also, removing the fender and last few inches of frame eliminated the installation points for the license and turn signals. Illinois is a horizontal tag state, so a vertical plate won't work.

I found a bracket that holds the plate and relocates the turn signals.



But I had nowhere to mount it. So I cut a piece of 3/8" plywood and shaped it into a big teardrop that fit just inside the bottom of the seat, with notches to allow for the seat hinges. I used a couple of conduit brackets to attach this to the cross-bar on the frame. This leveled out the seat and gave me a shelf to which I attached the bracket (after bending it to angle the plate out from 90 degrees).

That made the seat just a bit high, allowing the ply to peek out from under the seat skirt. So back to planing and belt sanding to take about 1/8" off the top face of the 2x12. Eventually, that lowered the lip of the seat to hide almost all of the platform board. When I painted the seat, I threw a quick coat of black on the board, and you cannot really see it at all.

Here is another pic with flash to better show the front of the seat.



When I get the rest of the beast back together, I will take some proper photos.