Clydesdales/Athenas (200+ lb / 91+ kg) - Stretching?

Runners almost always stretch before and after. Cyclists almost never do, or so it seems to me. Are there good reasons for this or is it just two different traditions? I haven't been stretching but I'm trying to do some longer rides now and feeling a little stiff the next day. If stretching is advisable, what kind of stretches should a cyclist do?

I stretch before, but it may be a carry over from my failed attempts at jogging.

Streching after is very important. Muscles tend to shorten up after exercise creating stiffness. Stretching beforehand not as important, but if you do it, be sure to warm up first otherwise you risk injury.

I do yoga most mornings, and especially when I cycle. When I don't I take longer to get moving at my usual pace.
I never stretch after but sometimes I'll stop and stretch a calf it is showing signs of knotting during a ride.

Maybe they stretch when you aren't nearby to watch?

Also, I do alot of my stretching on the bike. I also do a good warm-up & cool-down after most of my rides.

I stretch during (at rest stops) and after the ride. I warm up by not going all out the first couple miles, and a cool down the last couple miles.

Mostly just my arms. Anything the bike can do, I just let it do.

I stretch at my first rest stop, if it's a long ride. Otherwise I just save it until the end. Like someone mentioned earlier, when I get to the point where my calves start knotting up, I'll stop and give them a good stretching.