Originally Posted by alanbikehouston
Pro's ride whatever bike the team owner orders them to ride. The team owners are paid by bike companies to use a particular bike. Every rider in the Tour would be riding a Cannondale (or a Trek, or a Giant) if those companies made the team owner's an offer they can't refuse.
I would of guessed that if one bike company either had more money than others (some do), or if one bike was better than others, then either the bike companies would approach more teams, and teams would approach the same companies asking them to "match" sponsorship arrangements from other companies if one bike was much better than others.
Golf is an equipment driven sport I'm more familiar with. There might be outright best equipment, but familiarity is more important, and all the top level equipment have a nice balance of features, and reasons to prefer each item. But, Irons tend to be much more individualistic than drivers. Sponsorship loyalties prevent players from using the latest and best driver, while the sponsor products are all "close enough"