ok, here is the situation. My son is a pretty competitive Mt. Biker. He was racing jr's last year, and even though he is just 15 he has moved up to where he was running middle of the pack Mens Sport (cat 2).
Mt Bike season is over here...and cross season starting. Just to have more time on the bike, he wants to run a couple of cross races. Locally there are only 5 races. Sat/Sun this weekend. A sat in 3 weeks, and then another Sat/Sun in late November.
we are planning on just running his Mt Bike...then a buddy said go buy a relativly cheep vintage road bike (vintage because most older ones have more room for the fatter tires) and get some tires.
I guess I dont know enough about cross to know what the advantage of a vintage roadbike would be.
I have a Raliegh Grand Prix from the 80's, 700cc wheels...but its a 58cm...and he is 5'8" so I am thinking 55-56cm is right for him, and 58cm would be too big...but I dont know anything.