How to build your own bike

1. Design

The first step is to come up with a design. We used the Bike CAD program for this, working with

TBA’s Tom Sturdy. If we’d been making the frame for just one rider, we’d have done a full bike fit first. Because we want the whole team to ride our bike, we focused on getting the handling right. At this point, it’s vital to double check everything

– tyre clearance, seatpost insertion depth, etc. You don’t want to encounter problems halfway through the build.

2. Jig set-up

bottom An adjustable jig is used to hold the head tube, tubes are bracket shell and dropouts in place while the jig is first fabricated. To ensure everything is aligned, the are tightened calibrated using a laser and then the fixtures into place at the correct locations.

3. Cutting & mitring

With butted tubing, it’s essential to know where the changes in wall thickness are. This can be found out using a ‘butt checker’ (yes, really!). The tubes can then be roughly cut to length, before the ends are mitred. Bike CAD outputs paper templates for this, which can be wrapped around the tubes for marking. Then it’s a case of precise hacksawing and filing. Accuracy is important, both for the strength of the joint and to ensure the tubes sit straight. This process is repeated for all the tubes in the front triangle, after which it’s time to look at the rear end.

4. Forming

A CAD printout showing the rear triangle in plan form is used to check crank arm, chainring, tyre and mud clearances. By comparing the chainstays to the plan, you can see if any additional bends or cut-outs are required.

With the shape sorted, it’s time to cut and mitre the stays before fixing them to the dropouts.