I've been racing for two seasons now - road, cyclocross and some mtb. I've had some wins and this is how I'd like to make a living, specifically road racing or cyclocross. But I just turned 22 and realize that most turn pro in the 21 to 23 age, and there are still lots who turn pro even earlier, 19 to 20. Is it possible? Any advice? I've already decided to give it my best shot, because it's something I can't not do. Are there any pros famous or not who got good later than most?
None of us can offer you definite advice since we don't know who you are and the details of your schedule, your workout, your commitment, the level of competition, etc. There's a whole bunch of variables that are involved here.
But just realize that the odds of getting paid are already slim as it is, and a late start isn't going to help. Realistically, I don't think there's much of a chance for you to make it as a professional. By now, you know your body so you should be reasonably aware of how fit you are in comparison with other professional cyclists.
By the way, there seems to be some discussion on this here that echoes my thoughts.
Let me start by stating I do not have a great knowledge of the typical career path for pro-cyclists, so this answer deals mostly with the question of 'making it' in any sport beyond some perceived cut off age.
In any sport, whatever the age of the participants, the chance that any particularly individual, no matter how motivated and talented, will make it to the big time is slim. There are always many more people who want to make it than there are opportunities. Therefore regardless of your age, your chances of making it are small. That means you really need to love the journey, not just the hoped for destination. You have to love training hard and competing to your limit as an end in itself. If your performances are good enough, you will reach your goals but you have got to love striving or else you are setting yourself up for a giant disappointment.
What would you do in response to your question? If someone said "no you're too old" would you then not bother trying? If so then you probably don't have the innate love of competing that is a requisite of success no matter what your age is.
Just as a caveat regarding pro-cycling, I have several friends on the fringe of the 'serious but not pro' cycling scene and they are pretty much all on drugs. It seems that the dirtiest tier of the sport is those who are trying to 'make it'. The pros are probably largely clean these days due to the testing regimes, and the keen but never going to make it guys don't bother, but those trying to gain the attention of pro teams seem to be willing to take the risk as getting caught leads to no different outcome to not doping and not putting up a good enough performance anyway. What I hear of people using mostly is testosterone as hard training lowers the levels which take a while to recover. Artificially boosting this allows the 'athlete' to train harder and longer. A non-pro isn't going to be tested out of competition and there isn't anything in the body on competition day that would demonstrate the doping. I'm not suggesting you do this, far from it, just be aware of the dirty sport you are contemplating and the cheaters you will be competing against.