Question: What gears are they pushing? They look like they’re flying. —Jack G.
Pros often use a 55×11-tooth high gear for time trials. On flat or rolling stages they might have 53/39T chainrings with an 11-21T cassette. In moderate mountains they switch to a large cog of 23T or 25T.
These days, they’ve joined the big-gear revolution like many recreational riders. For very steep, long climbs or the severe tilts like on some of the Classics, they now go as high as 28T or even 32T cogs.
Remember, though, it’s deceptive to compare the pros’ gearing to your own. Top pros are strong enough to use a high cadence in whatever gear they choose.
When you can generate over 400 watts of power for an hour or more, like many of them can, you can maintain a high cadence in a lot bigger gear than the average recreational bike racer who puts out a little over 200 watts.