Joined: Oct 2016
Posts: 854
Likes: 334
From: Cambridge UK
Bikes: 1903 24 spd Sunbeam, 1927 Humber, 3 1930 Raleighs, 2 1940s Sunbeams, 2 1940s Raleighs, Rudge, 1950s Robin Hood, 1958 Claud Butler, 2 1973 Colnago Supers, Eddie Merckx, 2 1980 Holdsworth, EG Bates funny TT bike, another 6 or so 1990s bikes
Grand Tour tire pressure
"The fast guys around here (flat terrain, 27mph average speed for 60 mile group ride) are all on 28mm and all inflating to 60psi. They are full size riders"
One of the reasons pro teams are going lower is that rigid carbon bikes with huge BBs, head tubes and deep rimmed wheels need a softer tire to reduce road shock over 20 odd stages. Your fast friends must top well over 30 mph to get a 27 mph average. The TdF has a 200 plus pelaton and they are slower than your local speedsters and furthermore, nobody on the TdF rides a bike under 10K USD!
No pro team rides on less than 95 on the front and 105 on the back and many considerably higher. In the TT it's 120 psi and many of those riders will not average 27 mph.
At 60 psi I suggest your local speedsters contact every pro team in the world as they will all become very rich men indeed.
On the Paris Roubaix - the Hell of the North - wherein on some sections the cobble stones are so bad that riders carry their road bikes rather than ride over the pave the tire pressures are 85 to 95 psi. They still average 24 mph but those stones are so severe that the possibility that a lower pressure might offer some dividend regards a better average speed would be considered manner from heaven.
Last edited by Johno59; 10-22-19 at 11:35 AM.