Originally Posted by
pdxtex
Really, how do you know? Other sports have benchmarks that show your relative skill level. Can you run a mile in 6 minutes? Well you are probably a good runner. Can you do a kickflip? Well you are probably on your way to being a good skater. Oh, you can go down that black diamond? You get the point. So what makes a a cyclist "good"? Or accomplished?
Focus less on speed. Speed just makes you a "fast" cyclist. Fast <> Good.
Then just make up your own definition of "good" in terms of what matters to you.
I would probably apply the label "good" to someone who is quietly competent, approaches terrain with confidence, respects his limitations, treats others well (important!), rides his chosen style -- whether touring or road racing or BMX or whatever -- with some zest(!), respects and understands the various riding disciplines besides his own, has some knowledge of the bicycle and how it's put together, contributes to others' enjoyment of the sport, builds up cycling in his local community, helps newbie riders and those who need help, etc.
Some reasonable combination of the above probably = "good".