Benson’s 650B FGC

Benson asked me to build him a travel-gravel bike – so a good candidate for the Folding Gravel Concept. The pivots at the BB and rear dropouts allow the frame to foldup (once the wheels are removed) for packing into an airline checkable case. Going with the slightly smaller wheelsize of 650B, not only was a good option for this size bike, but makes packing the bike that little bit easier. Benson really liked the look of my custom stem design, but without a removable faceplate it isn’t a great option for a travel bike where the bars need to come off for packing. So I took a cue from Bike Friday and split and shimmed the bars – once the stem bolts are loosened, the bar comes apart in the middle and can then very easily be packed with the bike.

We pored over every little detail on this frame. Benson inspired me to explore some new technologies with a 3D printed headtube. This was a fairly involved process to allow me to experiment with the alloy and process, and perform destructive testing to determine the strength and properties. It was a lot of work, but we were able to achieve the look Benson asked for, which would have been prohibitively expensive to machine.

The toptube has a slight curve, with the seatstays dropped just-so, along with the seatpost binder being angled to match the stays. Carefully manipulated chainstays provide for maximum tire clearance whilst using a road crankset.

SRAM eTap is a great option for a travel bike, with no wires or cables to deal with when packing. Installed here in the 1×12 Force AXS version. The bike comes in at 18.5lbs as pictured.

Benson created the paint design, which was then painstakingly executed by Colorworks.

2 Comments

  1. Saw this on your insta, I’d love to see some folded pics though. Very clever solution for a large wheeled machine… though still wondering if the back end is stff enough! How tall is the customer? It might be that its dedicated 650b – but it looks “small”?
    The head tube looks impossible! Very neatly packaged.
    Cheers

    Toby

    • Hi Toby – I haven’t packed it yet, will take some photos then. You can find photos of some folded machines in the ‘travel bikes’ gallery. There is no loss of stiffness. In fact the first version of this was built when I wanted to return to the UK to race the National Hillclimb – built into a 12lb road bike. Not quite my sort of hill that year, but I managed 11th. Benson is 5’9″, although relatively shorter legs for a lower seatheight. The beauty of a custom build is that the bottom bracket height can be set for the required crank length and wheel/tire size, so that might be why it looks ‘small’!
      Thanks for your interest, Rob.

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