Φ Bultakenstein [Aborted]

I finished upholstering the seat yesterday. My stitch lines are a bit haphazard and the fit is slightly wonky in spots, but I’m not too disappointed. It’ll be a perfectly serviceable part, … Seat upholstery completeRead more

I’ve made some progress sewing the seat cover; the front half is done. It looks okay, but the bottom of it is a bit wonky. I’m not completely sure where I mis-measured. … Sewing the seat coverRead more

I’m working on upholstering the seat for Bultakenstein. For the foam padding, I am using 1-1/4” thick yoga mat I bought off Amazon. I also bought some pre-made diamond-tuck quilted vinyl for … Cobbler’s sewing machineRead more

I’ve been chatting with some Bultaco experts about an expansion chamber designed to my Alpina cylinder. The short answer is that I can’t find evidence of one. Even when going with aftermarket … Exhaust designRead more

I did some timid lightening of the seat base and bolted it to the Airtech shell. After I took these photos, I temporarily spray-glued three sheets of 1/2″ polypropylene packaging foam to … Continuing with the seatRead more

I’ve never mounted a fiberglass seat before, so I might be going about this all wrong, but I knew I needed to add some sort of additional structure under the seat to … Seat base fabricationRead more

Playing around with color ideas today. I’m going to try to match the red color of the tank, but I’m planning on reversing the base color and accent color on the seat … Brainstorming graphicsRead more

I think I can make this seat work. I measured points a consistent distance back from the back wall of the seat, then used a contour gauge to transfer the inside shape … Closer seat examinationRead more

The Norton Production Racer seat pan arrived from AirTech Streamlining a couple weeks ago, and I’m super disappointed in the quality. I still think the shape of this design is perfect for … Proddie seat is warpedRead more

I decided I wasn’t happy with my original chain guard’s homespun appearance. Thanks to purchase of dimple dies and a bead roller, Chain Guide 2.0 has turned out much better. It took … Chain guard #2Read more