Originally Posted by
PiLigand
about a meter from the guy in front of me?
Depends on the situation, your skills, and your own personal risk balancing.
A meter behind might be fine for a recreational group ride at 18mph.
In a fast competitive group ride, it's likely to get you dropped (and likely yelled at by the people behind you)
In a race, it's going to get you quickly shuffled to the back because someone is always going to fill that meter of space.
How close I'm going to draft someone depends on the situation. With a group of people that I have some confidence in, typically 3-4 inches. If the rider I'm drafting appears sketchy, I'll give them more room, or just drop off the back or go off the front.