Our Tour de France Grand Dpart tech gallery revealed more spacers, shorter cranks and more forward saddles than ever before in the pro peloton. These are things bike fitters have been advocating for years, but professional cycling can be resistant to change, particularly with regards to bike set-up. Tradition and aesthetics long dictated that slammed stems were faster and de rigueur. As our tech editor predicted before the race, Tour de France cyclists have raised their stems for better comfort and potentially aerodynamics. Following the lead of Tadej Pogaar, sub-170mm cranks are more widespread while the relaxation of the UCI's saddle setback rule has brought seats over the bottom bracket. To explain why more professional cyclists have seen the light, we've spoken to professional bike fitters Bianca Broadbent and Dan Smith, and Sven Reutter, Canyon's road product manager. You can lead a horse to waterIn a supposedly data-driven sport, traditional aesthetics are surprisingly important. (Image credit: Aaron Borrill)"The biggest trend for me is that a lot of ideas that were once considered unconventional have now become completely normal and acceptable," says Smith, of UK Bike Fit, who has also worked with WorldTour cyclists such as Ben Swift. "You can lead a horse to water, but you can't make it drink," says Broadbent from Fit Your Bike, who has fitted numerous international and professional cyclists. "There's an emotional side and the scientific side to bike fit. A lot of the time with professional cyclists, emotion will rule. "How do you feel on the bike? I feel that when my stem is slammed, I feel that my bike is faster, therefore I will be faster.'"If their emotional state changes, they're more likely to want to change their fit."(Image credit: Aaron Borrill)"In the pro ranks, generally speaking, riders have changed their position in the last couple of years," says Reutter. "Saddles have moved forwards, cranks have shortened, and cockpit heights have got both higher, and widths are narrower."While the Canyon product manager is right to say handlebar width has decreased, the UCI, cycling's governing body, has halted ever-narrowing shifter hood positions. In addition to a minimum width of 400mm across the handlebars, there must be 280mm between the inside of the shifters. This ruling is arguably more unfair to women than men, since women typically have narrower shoulders, but Broadbent says the majority of male WorldTour riders she fits are on the limit. "There are a lot of guys who want their shifters closer together but unfortunately can't," she adds. "It's a case of nothing can be done." There are, of course, exceptions, says Reutter, adding: "There are different preferences for every rider, with some more on the traditional side of things, some more open to change and more progressive setups."The rise of stem spacersOnce almost taboo for pros, spacers are now increasingly common. (Image credit: Aaron Borrill)"Ive noticed the return of spacers," says Smith. "For years there was almost a stigma attached to running spacers under the stem because slammed equalled fast. Now we're seeing riders and teams becoming much more accepting that a slightly higher front end can actually produce a faster rider over the duration of a race."It's been clear for a while that the fastest position for a lot of riders isn't necessarily the lowest position. If increasing stack height allows the rider to relax their shoulders, maintain a better head position and sustain their aerodynamic posture for five hours instead of twenty minutes, that's a win."Reutter also teams are less focused on the smallest possible frontal area and pay more attention to "sustainable aerodynamics". "A higher cockpit position might be slightly less aerodynamic, but when you add in the rider and how long they can hold this position, the net result can help the rider in total drag resistance," he says. Fatigue management has also influenced cockpit height, according to Broadbent. "The lower the cockpit, the more pressure on the saddle. So that's the longevity issue, in terms of sustainability," she says. "If you're racing long-distance stuff like stage races, the Tour de France, after a few days in the saddle you're going to feel knackered."Nonetheless, we still see riders in aggressive aero positions, such as Baptiste Veistroffer, potentially because they've calculated it's worth adopting. Baptiste Veistroffer riding low on stage 5 of the Tour de France (Image credit: Getty Images)"It depends on what you've measured in the wind tunnel," she adds. "If you can see like a delta of 10 watts with a higher and a lower cockpit, you're going to go with whatever's fastest, even for short durations, because you might accelerate away, get in a breakaway and work in a group where you don't need to hold that aggressive position all the time."The fact that wind tunnel testing won't necessarily reveal lower is faster is another reason cockpits have come up."We've had athletes in wind tunnels who have had a really unsustainable position and a very low cockpit," says Broadbent. "We brought them up, raised the torso angle and thought: 'Crap, this is going to be slow'. And it's actually faster. "Conventionally, what happens is if the cockpit's too low, people push themselves out of position."Forwards saddles and shorter cranksEven taller riders such as the 1.86m-tall Paul Seixas have 170mm cranks. (Image credit: Aaron Borrill)Moving saddles further forward and shortening cranks are trends that have caught on simultaneously because they have similar objectives. "Both open up the hip angle for better blood flow and enable a more aerodynamic position," says Reutter. "Additionally these adjustments reduce stress points and knee compensation movement.""We're also continuing to see riders moving further over the bottom bracket, particularly as shorter cranks allow greater pelvic rotation without excessive hip closure," says Smith. "This allows riders to produce power from a more stable pelvic position whilst also supporting those higher, longer front ends. Again, it's part of the same overall philosophy rather than an isolated change."Tadej Pogaar is one of the most famous exponents of shorter cranks, and while some cycling fans are sceptical of the benefit it has brought him, and others, bike fitters like Smith can see the positive effect of finding the optimal crank length for a particular rider. "Watching Pogaar's stage win on 14 July, what really stood out to me was just how open his hip angle remained at the top of the pedal stroke when climbing the last rise to the line," adds Smith. "Historically, if a rider had been producing that much power in such an aggressive position, you'd expect to see the hip much more compressed. Instead, it looked incredibly open and unrestricted."Broadbent also says the 'Pogaar effect' has convinced more pros to go shorter than the traditional 175mm and 172.5mm cranks. "We've been trying to get people on shorter cranks for years, but the main problem was belief," she says. "So when Tadej put shorter cranks on, people said to me: 'I really want to do this', although they said no when we discussed it the year before."However, short cranks haven't been adopted across the board because they won't necessarily work for taller riders, as Wout van Aert's experimentation suggested, and have knock-on effects."There is a risk involved because you can't put on different cranks without the data to back it up," says Broadbent. "Although you can compensate for shorter crank length to a degree, it will have an impact on certain scenarios where you do need leverage."Is the answer progressive geometry?The Ridley Noah Fast 3.0 typifies 'progressive geometry' with its steep seat angle and long reach. (Image credit: Ridley)So-called 'progressive geometry' is becoming a bike-fit buzz word. This geometry, famous in mountain biking and seen on the likes of Factor's One, lengthens the reach and pushes the rider over the bottom bracket, eliminating the need for long stems of the past. Its proponents argue it can rectify the compromised handling caused by more forward positions. "If 'progressive geometry' means steeper seat tube angles, taller stacks and longer reaches that naturally position riders further over the bottom bracket, then I wouldn't be surprised to see manufacturers head further in that direction for race bikes," says Smith. "Historically we've seen many pro riders using 130-160mm stems, sometimes even having custom stems made to achieve the position they wanted. If the frame itself provides more reach and a steeper seat angle, those extreme stem lengths become less necessary. For professional riders, progressive geometry makes a lot of sense."But he is more concerned about how consumers will deal with such geometry. "Professional riders are an incredibly specific population. They're exceptionally flexible, produce huge amounts of power and spend enormous amounts of time adapting to aggressive positions. Recreational riders generally don't," he adds. "If everyday riders are placed significantly further over the bottom bracket simply because that's how the bike is designed, we could start to see more issues relating to weight distribution, upper-body loading and overall comfort. A position that's ideal for Tadej Pogaar isn't automatically ideal for someone riding three hours at the weekend to the cafe and back."I suspect manufacturers will continue building bikes around the demands of the WorldTour because that's what sells bikes, but I think fitters may end up having to work even harder to adapt those bikes to normal riders."Broadbent is more skeptical that pros need progressive geometry, such as longer frame reach, to get their fit."When manufacturers provide stems up to 140mm in length, that is probably okay, as long as the frame geometry is reasonably long," she says. "It's not like on the track where stems sometimes need to be 180mm."She also believes it would be rash for bike designers to make taller head tubes."I think that might be what you want aesthetically and aerodynamically, but you also need adjustability. And if you start coming up too much, then you lose the ability to reverse adjust that. "I think you want consistent data to see what that's like over the course of multiple seasons before you start making that permanent change. After that, if you want to get lower you have to size down the frame and then you have the issue with the length. For example, not everyone sticks to shorter cranks; some people change back to longer ones."Customised touchpointsSaddles could be about to become more personalised to riders' needs and preferences. (Image credit: Aaron Borrill)There seems to be more attention on personalising bike fits, whether that's through overall measurements or components. "There might be more scope to go down the custom saddles route," says Broadbent. "Your limitations mainly are manufacturers and their ability to lend resources to it while making a cost-effective product. But the advent of more mass-scale 3D-printing makes it easier to offer personalised solutions, so long as that 3D infrastructure is appropriate for that person.""In general it's important to understand that a good bike fit is pretty specific for every rider," says Reutter."At Canyon we try to create a bike where every rider can achieve their personal best position, this is the reason why we offer different setbacks for our seatposts, lengths from 70mm to 140mm in the cockpit and a whole range of dropbar options, customisable drops, plus a one-piece cockpit. We are increasingly supporting these options with drag testing on the track and in the wind tunnel to find the most efficient position."The universal pro bike fit is on the way out, according to Smith. "I've noticed that the positions across the peloton are becoming less extreme and more individual," he says. "Ten years ago there was almost an expectation that every GC rider should be as low and stretched as possible. Now there seems to be greater acceptance that riders can arrive at different solutions based on their morphology, physiology and riding style."He has also seen bike fits become more rounded, considering aerodynamics, biomechanics and performance all together. "WorldTour bike fit is not just about comfort or injury prevention or CdA," he adds. "It's becoming an all-round position where the goal is to find the fastest position a rider can actually sustain over the duration of a three-week race."Variable bike fitsFlat stages could allow some riders to relax their fit. (Image credit: Getty Images)Reutter says certain riders on Canyon-sponsored teams (Alpecin-Premier Tech and Movistar in the men's peloton; Movistar, Fenix-Premier Tech, Canyon-SRAM in the women's peloton) slightly change their position during a stage race."Especially at Grand Tours, some riders have kind of off days," he says. "The goal is purely to recover as much as possible. Some riders prefer a more relaxed position on such days and go, for example, for our Compact Drops [which have a shorter drop and reach]. "This approach is rather new to the pro scene and were constantly exploring possibilities in this direction."Notwithstanding the potential benefits, professional cyclists probably won't be able to significantly change their position."I think in an ideal world you would potentially have a slightly different position for one-day races and Grand Tours," says Broadbent."Having said that, these guys are very well trained. They're exceptional athletes and it depends a little bit who they are. "If you're a sprinter, it might be more crucial to think about having a more relaxed position on non-sprint days. But the reality is, from a logistical point of view, it's just very, very difficult for teams to do that."Spacers can't easily be added and removed from integrated cockpits once the steerer has been cut, and it would place high demands on mechanics to swap steerer lengths. But given how much pro bike fits have changed lately and how much teams' budgets have grown, maybe stage-specific bike fits will become the next frontier.