Custom Frame - Adjustable seat post angle - experiments with seat masts

Somehow it seems to me you've sort of made a flying gate.

Yeah, in the way the seat tube and seat post become separate entities.

As if you knocked that out in 2.5 days! Good effort.

Cheers. My neighbour cnc'd the bridge and clamp for the seatmast, I machined the rest.
Yeah. It's possible to build a conventional simple frame in a long day if you have a mill.
And alot quickest if TIGing batching.

Sanding the brass takes time ontop and adding fine custom details, dropouts etc 🙏 and the time discussing what somebody would like.

Looking great Sam, get that picture up of it in the wild !!

Cheers! :) I took it for a ride and it felt great, solid but smooth on the 45c tyres.
I want to build a skinny tube version next, 1" fork and the like.

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Saw these at Bespoked, didn’t get a chance to chat but they looked bonkers & well executed.

Thanks 👍🙏
I tried some 27.5 X 2.2 on the bike today.
Loads of room.
This is with the DUB rival wide chainset that gives an extra 2.5mm room, and a 73mm BB, 40t chainring and a small dimple on the outside of the chainstay.

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Hey, just stumbled on this thread after seeing the Bespoked content. Very cool. The angles are quite pleasing on that frame, it hardly looks out of place. (Here's that 78° STA frame I mentioned in an ig comment.)

Does that mean slender steel forks and rim brakes as well?

Hi Yemble,
Thanks! That's a great build. I quite like being over the BB too, I think it's where I was commuting on old TT bikes for 5+years or so.

Yeah, that would be nice wouldn't it - keep it slim and light.
I'd like to do an unpainted stainless fillet brazed one... but we'll see about that.

à la Kirk Frameworks 😍

Ah yeah, Kirk quality would be the dream... stainless/silver brazed frame with titanium adjustable seat mast.... one day.

This project came across my mind yesterday. How's this thing keeping up?

I haven't managed to use it much to be honest but it's held up solidly when I have - it's rock solid. But I've come to the conclusion that this kind of adjustability is best suited to a cargo bike (different riders jumping onto it) or kids bikes (growing all the time) - something where performance isn't high on the list of priorities and adjustability is....

Late to the balance bike party, I made this one recently. Very light but very crude unfinished afternoon rush - lots of angle grinder involved. It's from the tubes I got from Dave Yates. Every child needs an aero downtube don't they.
I've got some powdercoating equipment going in this weekend so I'll coat it next week.
The next one will have an adjustable seat mast though - room to grow and all that!

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It gives baby Brooklyn machine works vibez

Yeah, big stem looks a bit BMX doesn't it. I need to make another one and some slim bars/grips for little hands.