At the end of Tour of Italy we went into the details of the uphill bikes and related technical choices, those used by the protagonists. Now let's try to analyze the metric developments of the most used ratios by the pros on the roads of the Giro d'Italia.
Heart and head, legs and lungs. Character, strength and determination and that hunger for victory are the first aspects that belong to a champion, but it's not just that. Today, technical choices There are many options available to athletes and they can become the deciding factor, but it is important to adapt them optimally to your needs.
Technical choices? Many variables at play.
We have analyzed the technical choices of the protagonists who fought over the latest and most important climbs of the Line of BusinessWe made a sort of overlapping relationships (and related metric developments) of the groups Shimano and Sram, the two main players who technically competed for the podium.
Before going into detail, it is useful to underline once again that, the Giro d'Italia 2023 It will also be remembered as the first stage race where many riders (not just a small circle) have used the single crown for time trials. We've seen some 60- and 62-tooth "patelloni" (trials with 64-tooth chainrings are already underway). A gravel drivetrain with a single chainring wins a stage with an uphill finish (the last time trial on Saturday with the finish line on Mount Lussari). Not only uphill though, as during the last stage in Rome, Roglic used a Cervélo S5 with single chainring front and 12 rear gears.
Like it or not, This year's Giro d'Italia was very rich from a technical and technological point of view, a factor that is bound to make change beliefs and choices with a view to the future, even from the same companies that supply the materials to the teams.
Shimano and Sram compared
We tried to make a sort of comparison between the most used ratios in view of the climbs, considering the metric developments with the standard value relating to the diameter of the wheels and the 28 tubeless ones (the most used in the group).
The most used sprockets for climbing start from 17 to 34 for Shimano riders, 33 and 36 for Sram ridersThe largest sprocket is sometimes not even taken into consideration (crisis aside), because the difference is made with the ninth, tenth and eleventh, thanks to an optimal compromise between metric development, agility and chain line. Furthermore Shimano riders used the 54-40 front plate, while Sram athletes used the 52-39 chainrings (aside from climbing Mount Lussari).
Shimano sprockets with 11-34 scale can count on the 30mm sprocket (the penultimate), widely used with the 40, but also with the 54. This latter is an unorthodox intersection, but it is widely used on gradients below 6-7 percent and in the attack phases of the climb. 17, 19, 21 and 24, 27 and 30, with metric developments per pedal stroke of 4,943, 4,423 and 4,002, 3,501, 3,112 and 2,801 respectively meters.
For the riders who used Sram (with the 39 internal chainring) the gear ratio scale is identical for the first 4 sprockets, i.e. 17 and 19, 21 and 24 (with slightly lower metric developments due to the 39-tooth chainring), but features 28 instead of 27, with a significant “jump” to go directly to the last gear with 33 teeth (Red sprockets). The metric development of the 39×28 combination is 2,926 meters.
Sram's Overlays
If we analyze each single combination, we notice that the two transmissions are quite balanced in their metric developments, with differences ranging between 40 and 50 centimeters, from one sprocket to the next. In the logic of the climber, the presence of 30 can be an advantage, to be used with the internal crown and with the chain on the 54. The 54×30 chain crossing (Shimano) has a metric development of 3,782 meters and does not overlap with any of the combinations used with the 40 crown. The 52×28 (Sram) cross-section develops 3,901 meters, an value identical to the combination 39/21 and in fact another ratio is lost that could be exploited under conditions of maximized performance.
Another Sram overlay, always considering the metric developments, is noted with the use of the 10-36 sprocket scale, used by Roglic (with the double crown 52-39), which however has the 32 as the penultimate ratio. In fact, with the 52 in front and the 32 in the rear you get 3,414 meters of development on the ground, the same as the 39×24 combination. The cassette with the 32 is very advantageous on long climbs and with sections well over 10 percent, thanks to a development of 2,560 meters.
Single chainring and everything changes
The captain of Jumbo-Visma, for the climbing the Three Peaks of Lavaredo (opening image) used a Cervélo R5 prepared with XPLR drivetrain (10-44 rear) and single chainring front 42 teeth, the same one used the next day for the climb to the Mount Lussari.
Taking into consideration the last 5 sprockets we notice a progressive scale: 24 and 28, 32 and 38, to then arrive at 44 as the last one: 3,640 and 3,120, 2,730 and 2,299, are the respective metric developments with the wheels adopted by Roglic (also considering the 25 tyres), without forgetting the metric development of thelast combination (42×44) of 1,985Wanting to do a comparison with the last combination Thomas had available, 34×34, the Welshman could count on a development of 2,101 meters (with 28 tubeless), only 11 centimeters more than the Slovenian.
Did the technical choices influence the final result? The answer is yes. Roglic he used gear ratios with a lower metric development (so for each single pedal stroke he covered less distance). The winner of the pink jersey, during the hardest stages, he had more opportunities to exploit his way of pedaling, very more agile compared to Thomas, Almeida and all the others, thus increasing the distance traveled in a shorter time. On the climb up Mount Lussari, Roglic averaged just over 90 rpm., Thomas just over 80. Centimeters that became meters, not many, but that were translated into those final 14 seconds. And just a strategy suited to the characteristics of the rider in technical choices it might have made the difference.
