This is an experimental fatbike frame, with a very short chainstay length of 430mm.
Paragon dropouts, PF30 bottom bracket, 44mm head tube, and made mostly from Reynolds 853.

Folding Bikes, Recumbent Bikes & Trikes, Cargo Bikes, Tandems, Custom Framebuilding
This was a lovely handmade Soulcraft frame, which had an unfortunate high-speed incident with a bench – the rider also lost a couple of teeth, but he was probably more upset about the damage to his bike!
So I made a new headtube and downtube, and fillet brazed them in.
Repainted, and it’s as good as new!
These bikes were for a couple who wanted to upgrade their existing Bromptons with Rohloff hubs.
It’s possible to match Brompton frame colours so the new rear triangle I fit doesn’t look out of place.
I do a kit if you want to upgrade your bike yourself, or I’m very happy to do the fitting here.