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Thermoplastic motorcycle seat construction

 

I am looking to create a custom seat for my Harley. My current seat is a two piece construction: rider seat(hinged sheetmetal base), passenger seat is attached to rear fender. I would like to use the existing hinged riders seat as a starting point for the construction of a one piece, two person seat. I would like to fabricate the passenger portion of the seat from a thermoplastic that I can form to fit the rear fender. Then attach the formed plastic to the existing riders seat and reapolster the finished one piece seat. Is there a plastic that I can form with relative ease in my own garage to complete this project?

Curtis Hart
- Grand Blanc, Michigan, USA

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Curtis,

My apologies for not replying earlier but I had just hoped that someone else, more qualified, would have replied by now.

Re your quest, um, well I don't have enough info to give any practical advice.

Firstly, many, most, ALL true thermoplastics can be heat formed. But this is something of an art.

My first thought was to use a urethane foam ... and this comes in varying densities. The heavier becoming more expensive. But it can be shaped fairly easily.

The next query is HOW is this (fully!) supported? Obviously, if you have a 250 lb passenger, you may have a problem, sorry, you WILL have a problem.

Go to a local thermoplastic fabricator and get their advice but take the Hog with you. On the face of it then perhaps a piece of ABS sheet might do ... it forms fairly nicely and is good on impact, too. Also you can intercement ABS to itself with the greatest of ease, better, I feel, than any other thermoplastic. Having, perhaps, an ABS quasi formed base that can be STRONGLY fixed to your bike, then you could easily cement Pu foam to it (don't use the cheaper styrofoam as you won't get the density and it is sure easily attacked by solvents) Thereafter you can reupholster that piece.

Good luck.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).