Extra wheels during races?

Well I cannot say that I have seen anything like that before, but I have also not really been to many events like that where they would be seen, so maybe it is just the lack of exposure for me. Either way, though, I guess that is nice of them to offer help should someone need it during the race. My guess is that it would be a significant time constraint, but maybe people just want to finish the race so this will help them accomplish that.

More than extra wheels, extra tires. I guess you will need some logistics to fast replace them for any eventual accident and don't get left too behind from the race.

They are actually very fast. They are the trained mechanics and they fix the tyres in less than 30 seconds and the racer gets the chance. I also used to think that if it will take a lot of time to repair the bike but that's actually not true. Actually, I asked this question to a bike mechanic and he gave me all the information about this. He explained me in a very interesting way.

I think that you don't need extra wheels considering the time that you have and your competitors. A professional cyclist should know about the brand of tires he should be using in competitions. Since competition is about time, one is likely to lose if they can stop to change their wheels. In a competition, one must use new wheels or check the mechanic for any advice if he/she suspects that something is not correct.