Earlysport
Likes Bikes
I'm a fan of the pivotal seatpost system from BMX ( simple, light, great range of seats ) but have struggled a bit in finding a 30.9mm post to fit my Nomad. Alienation do one but getting it shipped here was a headache, and I'm not a fan of using a shim. So I set about some simple fabrication to put one together and thought I'd share in case anyone wants to do the same.
I had a Thomson layback post off my bike, and bought a $15 dabomb 27.2 pivotal post online. First step was to cut a length off the Thomson that I need, and cut the top off the dabomb post with the pivotal head.
The Thomson post has a cool oval inner diameter for lightness and strength. The dabomb post had very thick walls making it heavy for what it was (which would have been another disadvantage to using it with a shim)
Noting the oval inner of the thomson post, some work with the file ovalized the dabomb part to be a neat press fit inside the Thomson tubing. The ovalizing is also nice because it prevents the head from twisting inside the post when pressed together.
Some epoxy for security and then light pressure with a press pushed the two together to make my 30.9 mm thomson pivotal post..
I'll weigh it in the next day or so but I can say it's definitely lighter than the Thomson elite original. You can look around at Pivotal seat weights and find they're pretty light too for the comfort they offer. Of course you could use a cheaper post than a thomson and do the same thing - it's just I had the Thomson laying around.
Oh and I still have what is now a stubby Thomson layback post that I can still use or will find it's way to the girlfriends bike sometime soon
Cheers.
I had a Thomson layback post off my bike, and bought a $15 dabomb 27.2 pivotal post online. First step was to cut a length off the Thomson that I need, and cut the top off the dabomb post with the pivotal head.
The Thomson post has a cool oval inner diameter for lightness and strength. The dabomb post had very thick walls making it heavy for what it was (which would have been another disadvantage to using it with a shim)
Noting the oval inner of the thomson post, some work with the file ovalized the dabomb part to be a neat press fit inside the Thomson tubing. The ovalizing is also nice because it prevents the head from twisting inside the post when pressed together.
Some epoxy for security and then light pressure with a press pushed the two together to make my 30.9 mm thomson pivotal post..
I'll weigh it in the next day or so but I can say it's definitely lighter than the Thomson elite original. You can look around at Pivotal seat weights and find they're pretty light too for the comfort they offer. Of course you could use a cheaper post than a thomson and do the same thing - it's just I had the Thomson laying around.
Oh and I still have what is now a stubby Thomson layback post that I can still use or will find it's way to the girlfriends bike sometime soon
Cheers.
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