I posted this in the gear forum, but thought I'd post here too.
So I'm looking to get into road racing next year and have begun to look at road bikes after only riding a tri bike. I don't have a lot of money to spend, so am therefore looking to buy used. A lot of the used ones are 9 speeds. Since almost everything is 10 speed now, would it create any problems to have a 9 speed? Would I have trouble with neutral wheels at races? What about finding replacement parts, would that be difficult? Or anything else I haven't thought of
My old road bike was a 9 speed, my wifes old road bike was a 7 speed and I upgraded it to 8 speed. I had the choice of getting a 7 speed, 8 speed, or a 9 or 10 (if I wanted to replace the derailure at the same time). These things are pretty well supported for quite a long time. That wouldn't worry me and you could probably upgrate it eventually if you really wanted to.
I still have 2 9 speed bikes and 2 10 speeds. Finding 9 speed parts isn't a problem. It's been a while since I've done a road race (2007) and they did have 9 and 10 both. Pre-race instructions were to tell the guy as soon as he got off of the support car and he'd grab the correct wheel. They also had Campy and Shimano both.
For cyclocross, they just give you a pit bike for 1 lap. Flat peadls make that an "interesting" experience though