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Road Bikes vs TT Bikes

Cycling Time Trials host a number of road bike only events each year. These are marked in the event information, often with road bike categories being entered separately to time trial bikes. These provide an accessible route into the sport - which can be expensive if a new bike is required to be competitive. Road bike time trials allow road riders to compete on a level playing field, but the times are often slower as a TT bike allows the rider to get into a more aerodynamic position. This means that a rider on a TT bike can achieve a lower cda, a measure of how aero a rider is, meaning they can ride faster for the same power. 

The question is, how much difference does that make over a specific course? Cycling Time Trials have been working with myWindsock to work this sort of thing out. Let’s start with an example…

The P183 

This time trial, organised by the wonderful people at Sotonia Cycling Club, is a classic season opener for anyone near the beautiful New Forest. 

 

This early season race is a popular ‘road bike’ time trial, meaning riders who comply with the CTT road bike rules will be eligible for overall and category victories.

How much difference would a TT bike actually make? 

Let’s imagine a rider and bike that weigh 60kg and have 180W at their disposal for the course, as it’s a slightly rolling course we will give them 180W on the flat, 200W going uphill and 150W on the descents. A typical road bike cda is somewhere between 0.3 and 0.4 and we will use 0.3 here as our rider is small. Let’s plug the numbers into myWindsock and see what we get! 




27kph, not too bad for a solo rider on a road bike! Now, imagine our rider spends the following year saving up for and buying a time trial bike then they head off to get a fit and a little bit of other aero gear. This is a small rider so their cda gets down to 0.2 - how much time will our TT bike save? 

 

We see a huge saving of over five minutes with a TT bike here. A TT bike is only faster if you get a good fit and train in the position, but massive savings can be made. If you’re a slower rider, the power savings translate into much bigger time savings too! This tells us two things. The first is that if you want to take TTs more seriously, you need a dedicated bike. Secondly, it shows us how important road bike time trials are as an entry point into the sport. 

myWindsock

One rather neat feature of myWindsock is the ability to create a couple of different profiles on any given course, so you can compare a TT bike to a road bike and much more - we have barely touched on the available features. CTT and myWindsock have been working together to produce some content which shows riders how weather information can be used to plan their events. Look out for some in depth analysis upcoming of the big races this year! 

If you’re interested in adding a little bit more certainty to your time trial performance, click here to sign up to myWindsock. Good luck in those early season races!