Gearing choice in the Tour used to be easy, a standard chainset was the only way to go and cassette choices were limited at best. However, these days, with 12-speed options from Shimano, Sram and Campagnolo all represented in the peloton, there's more choice than ever. We've had a nosey at the pro's bikes to see what they're using this year.
The peloton's gearing choices differ from many consumer bikes simply because the riders race at very high speeds and therefore need bigger gears to keep a comfortable cadence. Whereas most bikes you can buy come specced with 50/34t compact or 52/36t chainset, (or 48/35t and 46/33t on Sram 12-speed groupsets paired with 10-tooth start cassettes) you'll typically find the peloton powering along on chainsets with larger chainrings.
(If you need a primer on the basics of gears and all the lingo, check out this article).
Cassettes have varied much more over the years, largely as a consequence of the steady increase in gears, from the old days of 5 and 6-speed to the 12-speed setups that are currently used in the pro peloton.
As the number of gears has increased, so too has the range, with bigger cassettes increasingly common, partly as a response to race routes that are getting ever harder as race organisers attempt to find even more cruelly savage mountains to send racers up. Take stage 18 with an intimidating finish up the Hauticam, to give one brutal example.
The increase in the number of gears also means that riders can get away with a larger range cassette as the jumps between the number of teeth are much more manageable.
We've also noticed a lot of pro riders using non-standard chainring sizes, particularly sprinters so they have some extra oomph in the last 200 metres of a sprint finish. For example, below is an example of a 54/42 Shimano Dura-Ace chainset that we snapped on Peter Sagan's now defunct Venge back in 2019. At the time the largest size that Shimano offered to the public was a 'standard' 53/39, the latest generation of Dura-Ace is available with a 54/40T.
A 42t inner ring seems a little odd these days, but 20-30 years ago a 52/42t chainset was pretty popular. Another place you'll find absolutely huge chainrings is during the time-trial stages. For example, during Stage 1 of this year's edition, Stefan Bissegger was spotted using this 64T chainring that is not available to the public.
The most common cassette size used in the peloton is an 11-28t. That is positively humongous compared to the 11-21t cassette that was common a few decades ago when you'd be lucky if you got an 11-23t for the mountains. Since Shimano went to 11-speed though, the 11-28t cassette has become popular.
With many riders using the same size cassette, it means a lot less work for the mechanics and wheel swaps are less troublesome. Of course, we do see some riders bucking the trend.
Talking of cassettes, another trend we’ve noticed in recent years is the increased use of Shimano’s 11-30t option. It's the sort of cassette size you once only saw on amateur bikes, not pro-race bikes. Above is Kasper Asgreen's Specialized Aethos that he used on last year's mountain stages which he chose to run with a 54/39t chainset paired with the 11-30t cassette. We're sure other riders will follow suit this year but we're yet to hit the high mountains.
Shimano Dura-Ace now offers an 11-34t cassette, Campagnolo offers 11-32t cassettes on its top-end Super Record EPS, and SRAM's 10-33t for Red eTap AXS goes even lower. With some of the steep climbs on this year’s route, we expect to see plenty of riders opting for these wide-range cassettes.
The number of gears on a road bike has increased over the years, with the cassette expanding from 6-speed back in the day to 11 -and 12-speed of today’s modern groupsets. For Trek-Segafredo, Movistar and other Sram-sponsored teams, it appears the 12-speed SRAM gearing provides enough range for mountain and sprint stages alike with many riders using the same gearing for both kinds of stage.
As we've already mentioned, SRAM is bucking the trend for big chainrings nowadays because of the 10t sprocket on its 12-speed cassettes. However, whereas last year the biggest it offered as standard was a 50/37t, this year we saw the introduction of 52/39t, 54/41t and 56/43t chainrings. As the previously available 50-tooth chainring coupled to a 10-tooth cassette sprocket gives a gear directly equivalent to a 55x11 gear (larger than the 53x11 used by most pros) this is likely to improve chain line rather than increase the largest gear.
Campagnolo-sponsored riders will have a similar choice of gears to choose from. A 53/39t chainset is common, with a smaller 36t inner chainring available for mountain stages. Cassette options include two choices, an 11-29t and 11-32t.
Campagnolo’s latest groupset is 12-speed, and one benefit is that the first seven sprockets go up in single increments. That’s ideal for finding your perfect cadence.
The death of the front mech has been long speculated in some parts of the bike world, but it’s rarely spotted in the pro ranks. A few riders have dabbled with 1x, with varying levels of success, and of course, there was the ill-fated Aqua Sport Blue team which solely used 1x drivetrains on 3T Strada bikes - the team boss at the time was quite scathing about either the drivetrain or the bike, or perhaps both.
There are benefits to a 1x system. There’s less duplication of gears that you get with a 2x groupset, it can be lighter and more aerodynamic, and it’s arguably one less component to potentially fail, which makes it popular with time trial specialists racing on flat-ish courses (here the lower chainring will just be ditched though). But it hasn’t caught on where a wide range is needed for variable terrain, mainly because while the range on offer with current groupsets is agreeable, the jumps between the gears aren’t.
One solution to this is the Classified system which basically moves the front mech into the rear hub, this could also bring aero benefits but at the moment we have only spotted it being used by one professional team - Uno X, they're not at the Tour de France and the system also raises some questions about wheel changes. Could it be something we see in the Tour de France in the future?
Today’s pro road racers are provided with equipment vastly superior to 10-20 years ago, but it’s the range of gears that has been the most interesting trend as the groupsets have evolved. As the number of sprockets has increased, the gear range has increased. Are riders getting soft, are courses getting harder, or is the higher number of gears making it possible?
The three big groupset manufacturers are still focused on the needs of the pro racers and delivering groupsets to meet their needs, and then selling them to the public, but there just aren’t many normal people that need a 54-11 gear. The requirements of the pros are very different to people like you and me.
This is slowly changing though. Outside of the pro peloton, we're starting to see a shift in focus from the equipment manufacturers to meet the growing diversity of modern cyclists that are less influenced by pro racers and more by their riding, whether long-distance road rides or adventure and gravel bikepacking. Largely thanks to adventure riding we're now seeing much wider range groupsets with more realistically usable gear ratios for the many people that don't go racing every Sunday, but want gears to help them out on challenging terrain and let them conquer every hill.
Jamie has been riding bikes since a tender age but really caught the bug for racing and reviewing whilst studying towards a master's in Mechanical engineering at Swansea University. Having graduated, he decided he really quite liked working with bikes and is now a full-time addition to the road.cc team. When not writing about tech news or working on the Youtube channel, you can still find him racing local crits trying to cling on to his cat 2 licence...and missing every break going...