Originally Posted by Iride01

I wouldn't recommend going blindly either by the manufacturers recommendation or even the effective top tube length. But for those that have nothing else to go by, it's still a good start. My only caveat would be if they know ahead of time that they have exceedingly long or short legs and arms. But conversation usually never gets to that point of asking here.

I'm surprised though that you had so much trouble on a 58 cm frame at 6' of height. I'd have to suspect that you go opposite of me and have short arms and legs for your 6 foot height. I have long legs and long arms for my 5'-11" height. I used to ride a 65 cm frame with no issues. I could even straddle the completely horizontal top tube flat footed.