It's probably the race where the bike counts the most. Starting with the optimal setup for the Paris-Roubaix can really make the difference. This is what happens in the most particular races: a Flanders, a (very fast) Sanremo, an extreme stage of the Giro... but in the race of the stones the value of the bike is truly important. And behind the victory of Sonny Colbrelli there is a Merida Reacto really special.
To reveal to us some gems of the jewel of Brescia is Alan Dumic, the mechanic of the Bahrain-VictoriousHe's the one who prepared Sonny's bike and followed him on reconnaissance missions.
Traditional handlebar set
«Sonny – says the Croatian mechanic – used the bike he usually takes, that is the Reacto (the aero one, in Bahrain they have the one available Sculpture, editor's note). But he changed the handlebars. Instead of using the integrated and aerial Vision, he opted for a normal stem and dropper post set. Fsa K-Force, Carbon fiber. He made this choice after the reconnaissance. This way, it would better absorb vibrations on his hands and the rest of his body.
«The measurements, however, were identical: both those of the handlebars (110 mm stem and 42 cm drop and position of the levers) and those of the saddle, height and setback.
We also added double tape to the handlebars, but not everywhere, only up to the levers: therefore in the bend and lower part, while in the upper part there was only one."
Very low pressure
Let's move on to the wheels. The most important part of a bike that's going to tackle a Roubaix, especially a bike like the Reacto, which is very stiff by default.
«We used tubeless tires from Shelf, a brand new tyre that arrived the day before the reconnaissance – says Dumic – but we saw and knew that it had excellent grip. This is the 32mm Gran Prix 5000 S Tr which we inflated to 3,8 bar at the rear and 3,4 at the front."
And here we're startled. This is a truly minimal pressure, almost cyclocross-like! And it's also a rather risky choice when it comes to punctures or pinch flats. And in fact, Dumic clarifies...
"Yes, it's a very low pressure, but it's also true that such a large tire needs less pressure. There's still a lot of air inside. For punctures, I added fluid like you do with tubeless tires. How much? Well, I added a little more than necessary: 80 milliliters instead of the usual 60."
The wheels finally were the Vision Metron with profile from 55 mm, but a circle whose internal width is 19mm and 27mm external A wheel that's very fast thanks to the teardrop design of the profile itself, but which, with the 32mm tire and that pressure, was also comfortable. And it's no coincidence that Colbrelli rode very well, despite it being his first Roubaix.
Very long relationships
And then you need to take a look at the gear ratios, something we tend to underestimate when tackling a Roubaix with the excuse that it's flat. Sure, the cobblestones aren't climbs, but they can become one, and even in this regard, there are precautions that can be taken. Dumic and Colbrelli have certainly grasped these.
In the era of large sprockets they opted for an 11-25, this way Sonny had a very good ratio scale. gradually and avoided the three-tooth jumps you see with gears that go up to 30 or 32. 172,5mm cranks.
«In front, however, we have chosen a 55-42. This solution was decided upon during the reconnaissance. The forecast was for rain, but also favorable winds for long stretches. The chain was the standard one, with the same number of links as the 53-39, so it always had good tension.
"How did I find the chain at the end of the race? Oh, I don't know, I didn't even wash that bike! It'll stay dirty because Merida wanted it that way, and it'll end up on display at their headquarters."
Goodies and superstition
«Another small intervention concerned the bottle cages – said Dumic – We use the carbon Elites, but for this race we chose the plastic ones that I tightened with a cut inner tube. The water bottles were actually harder to insert, but in the whole race our boys only lost a couple."
Finally, as a true Italian and given his personal history of bad luck, Colbrelli chose not to use the Italian flag-adorned bike. He was afraid it would break in the event of a fall, Dumic confided to us.
