Gear Ratios Explained For Triathlon | Choosing The Right Cassette, Chainrings & Shifters

Published on February 4th 2018


The gearing you have on your bike is such an important factor when it comes to improving your performance and your enjoyment, yet it’s possibly one of the most commonly forgotten things. So, let’s take a look at the gearing you should choose for a triathlon? Subscribe to GTN: Check out the GTN Shop: In association with Shimano. Gears really do have a huge impact on our riding. Gears that are too low, or too easy, may leave you spinning out, wishing you had a couple of harder gears. Whilst, gears that are too high, may bring you to a grinding halt on a steep climb. Firstly you have the chainset. Simply put the lower the number of teeth on the chainrings the easier the gear. So, there are a few common options with these. There is the standard, with a 53t outer ring, and a 39t inner ring. You also have the semi-compact, that has slightly easier gears, with a 52t outer ring, and a 36t inner ring. Then you have the compact, that is even easier again, with a 50t outer ring, and 34t inner ring. The other area you can customise your gear ratios is with your cassette. It sort of allows you to fine tune and optimise your gear selection and you’re not short of options either. Shimano cassettes come in a number of ratios including 11-25T, 11-28T, 11-30T, 11-32T, 12-25T, 14-28T! Whereas a larger number on the chainset means harder gears, on the cassette a larger number actually means easier gears. So, for example, I have quite a nice range on my bike as it goes from 11 teeth on the smallest sprocket, up to 30 teeth on the largest. So, it’s very well suited to a hilly terrain because I have a range up to 30 teeth. There are so many options when it comes to gear ratios but we hope this video helped you to understand what is available. If you found it useful, don't forget to give it a thumbs up and share with your triathlon and cycling friends 👍 If you'd like to contribute captions and video info in your language, here's the link 👍 Watch more on GTN... 📹 How To Bike Like A Pro - 📹 What Is The Optimal Cadence To Run Fast Off The Bike? -