Tom's TT bike

This is a bike that I have been excited about building for some time, not just because it is for me! Racing against the clock is my favourite cycling discipline and probably what I do best. I have always been frustrated with the notoriously poor handling of TT/tri bikes and so set out to address the issue.  

I am fortunate in that my racing position has remained the same for some time now and I am able to race both time trials and triathlons with only minor adjustments to the elbow pad height. This allowed me to look very specifically and the bike’s geometry knowing that my weight distribution will remain consistent whenever I ride the bike.

The conventional approach to designing TT bike handling is to adjust the front end geometry for increased stability at speed. Unfortunately this does not account for the inevitably high percentage of rider weight over the front wheel and the fact that steering geometry is limited by the rider resting on their elbows. This creates a bike that makes it difficult for the rider to make the continuous small, subconscious, steering adjustments to keep the bike upright and results in the notoriously ‘twitchy’ feel. 

I designed the front end geometry specifically to deal with this issue and then used a relatively long wheelbase to provide stability at speed. the result is a bike that feels as intuitive as my preferred road bike geometry to ride despite being in an aggressive riding position.

I wanted the bike to have as small a frontal area as possible with low brake levers allowing me to remain tucked for technical sections of races. This meant that a traditional 1.125” fork setup was not an option and so I designed a head tube assembly that uses full complement angular contact bearings to locate the integrated fork/handlebars to the frame using a much smaller frontal area (the widest part of the bike at this point is 25mm!) and a smooth transition to the top tube.  

The down tube and seat tube are specifically selected to give me the right amount of bottom bracket flex to really get the bike ‘planing’ along at race pace whilst remaining very aerodynamic (come along to my talk on Saturday to hear more about why a stiff BB is not always the right answer for speed).  I ovalized the top tube myself to keep the silhouette of the bike low whilst providing enough torsional rigidity.

The drivetrain is a 1x11 setup as I seldom use the small chainring when racing.  I opted for a track crank so as to improve the chainline and maximise drivetrain efficiency in the gears in which I usually race in. The cables have been routed internally but remain accessible enough for hassle free maintenance.

A proprietary bottle cage mount (which removes the need to drill and re-enforce tubes) has been added  to the handlebars to store a bottle cleanly between my arms. I also integrated some lights front and rear so that the bike is ready to race without having to strap anything else to it. these are powered by a battery housed discretely up underneath the saddle so that it is easy to remove for charging.

I went for a deep pearlescent blue colour scheme contrasted with some ‘tron’ style pink pinstripes, most of which have been hand brushed. I cannot wait to race this bike and look forward to some new P.B’s this season!

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