It's hard to say what 'too short' is. It really depends on what you do, where you do it, how hard you ride, how much you weigh, how tall you are, how experienced you are, etc. There's no magic formula for coming up with a correct length. If it feels long enough, then great.
'lets all go to hell for having sex!' Lateralis
'jib_this why are you such an ass? all your posts are dissing someone els (sic)' Krongos
'I can't type, I've been drinking' Nolan
Whistler Sucks