Designing a small frame that rides beautifully is hard. So hard. But we did it!
We're so proud to show off this bike as it's one of the truly greatest projects we've ever undertaken.
Cathy came to us looking for a bike which would replace several of her current bikes, fit her properly, and be lovely to ride. Not too much to ask, but when you're 160cm tall and want a road bike with disc brakes which can run up to 32mm tyres, it makes for quite a challenge.
Firstly we needed to find a frame builder. With a frame this small and the shapes required to achieve it, carbon was going to be the only real option. (You can only manipulate metal tubes so far, and this frame would require a huge amount of manipulation). This lead us to Plane Frameworks in Perth, who were keen to jump on board.
Pete then set about creating a geometry that would achieve the technical aspects Cathy was looking for but also do it in an aesthetically appealing manner. (She has to look at this bike every day, so we couldn't design something that looked like an eastern European tractor.)
It takes a huge amount of time to create a tiny frame which handles correctly. For everyone who rides a medium/54cm bike and larger, your bikes are easy to build; generally the numbers fall into place without too much effort (though you can still have a bike that handles badly if the producer has been lazy). Small bikes, in contrast, usually don't handle very well at all; they tend to be sluggish, corner terribly and feel very top-heavy. We've seen and ridden many small bikes -- even custom-made bikes by highly regarded frame builders -- which we would have sent back if they had been made for us.
For a frame this size, the dimensions are so tight that every millimetre counts, to the point where Pete was looking at 1-2mm and 0.1-0.2 degree adjustments to find the perfect balance between perfectly neutral handling characteristics (i.e. neither twitchy nor sluggish, which is what most small bikes end up being), maintaining the correct fit, and accommodating the larger tyres.
What made this even more difficult was the fact that, despite scouring the globe, we couldn't get a custom carbon fork made. This meant we needed to decide on a pre-made fork, then design the frame around it. (Going the other way will always lead to a mistake somewhere.) It came down to two forks, decided by which one gave the best overall geometry. There were compromises with both options, but one fork could have its only negative aspect countered through frame design, so that was our guy.
After many, many hours in front of the CAD software, constantly wondering if it was actually possible to build a small bike that handles well -- how come almost no-one does it? Was ours going to be a disaster? -- we were finally happy that we'd come up with a design that we hoped would work. (Side note: fear really stifles the ability to design freely!)
We sent the design to Plane, and after a couple of minor suggested changes (to make it look like a Plane frame), we were set to go.
We're proud (and extremely relieved) to say is the result is genuinely impressive. Cathy's bike is super-stable in a straight line but equally stable while cornering at high speed. Because of Plane's production methods and understanding of carbon, it's unbelievably quiet and smooth to ride.
To sum it up briefly, this bike is pure joy!