What special kit will teams and riders use for the Tour de France cobbles?

The Tour de France teams' mechanics will be working overtime to prepare bikes for the cobbles of Paris-Roubaix, which the Tour's riders will face on stage nine on Sunday.

The riders will change gearing, tyres and in Team Sky's case, the bike itself to use rear suspension.

"We are using Pinarello's K10S with suspension, that everyone should be on," Team Sky mechanic Gary Blem told Cycling Weekly. "Those come down this afternoon and will be at the hotel, and we will prepare them.

"With the rear suspension we don't need to run the tyres too soft. It's an automatic suspension so as we hit the cobbles the suspension is activated. That gives them more of an advantage on a normal surface before they hit the cobbles sections."

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Froome will use 54 and 44 front chainrings, 27mm FMB tyres and shifters on the tops of his bars. "You know I can't tell you that!" Blem replied when asked about Froome's tyre pressure.

"Froome will use the same setup as everyone else because you don't want one guy on something special in case you need to switch," explained Blem. "Some will use extra grip tape, some want extra shifters. Froome always uses the shifter up on the top of his bars and on the hoods themselves.

"We are trying to keep it standard tomorrow and not over complicate it," said Blem, who is coping on just six hours sleep each night. "It's been a hell of a lot of work for us."

Sky, like most teams, will organise a crew of "zone hoppers" to stand along the 15 cobble sectors with spare wheels, food and drinks. On the longer sectors, they will also be stationed midway along to help with punctures.

"It's like every year with the normal Paris-Roubaix day, there's more stress, but in our team it's pretty easy because we keep going on the same types of frame," BMC Racing mechanic Jean Marc Vandenberghe said.

"We are using 28mm tyres, which we also use in the spring. We don't want to tell you the pressure, but we need to find a balance for the tarmac and the pavé. The range varies by the types of tyres and the weight of riders.

"This stage is 100km shorter than Paris-Roubaix, so it means less kilometres of good pavement, so you can even go with a little less pressure which is better on the cobbles."

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The 156.5km stage nine from Arras to Roubaix covers 21.7km of cobbles spread out over 15 sectors.

None of BMC's riders will use discs in case leaders Richie Porte or Greg Van Avermaet, now wearing the yellow jersey and the 2017 Paris-Roubaix winner, need to take a wheel from their team-mates.

"We will ask the riders who wants double tape or shifters on the bars near the stem," Vandenberghe continued.

"Greg will also have have the little brake lever on the bars, but in my opinion, it's better Richie doesn't do it. Richie tried it in the recon. Greg is use to it, but you need to be ready to ride with your hands up on the bars."

"We are avoiding putting shifters up near the stem, you don't have much stability with your hands up there anyway," Enrico Pengo, mechanic at Bahrain-Merida said. "We are just sticking with what works."

Pengo is celebrating his 20th anniversary of working at the Tour, where he works on the bikes of GC contender Vincenzo Nibali and his Bahrain-Merida team-mates.

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"We've been preparing for this day for a long time. It's not just the bikes, but we need to have the wheels ready for all the sectors. It's very hard," he explained.

"The riders will use a 53 with a 44 or 46 inner chainring. Vincenzo will decide later. It helps to have the 44 or 46 if your electric shifting stops working so you can still race with a 44 or 46.

"The tyre pressure? It depends on the weather. When Vincenzo previewed the cobbles in April, it was colder. But normally, you are looking to be in the range of 4.5 to 5.5 bar [65 to 80 psi]."