Road Cycling - Group riding .. how much faster?

I've never ridden with a large group before and was wondering how much faster you could expect to go when riding like this versus going solo?

I'm sure the answer would vary and be dependant on a few things such as the strength of riders within the group, size of the group, terrain, riding formation(?) etc ...
... makes things a bit open ended.

Perhaps some of you would like to share your experiences of your first group ride? What your thoughts were? How much you enjoyed it? How much faster did you go?
:)

there's two things that make for greater speed -

1. social facilitation - almost all people tend to do better at a task when other people are around.

2. drafting - one word: aerodynamics. The fastest I can go around this 3 mile loop in my neighborhood is 21 mph. I was cruising behind my friend with less effort at 26mph.

So I'd say you can probably do 4-5mph faster in a group. More with faster rides, less with slower rides.

This past Monday was my first ever experence drafting with another rider. What can I say except it ROCKS! I can see how a team working to gether can make a much faster time than individuals alone. I was always fresh for a pull at the front, because I could rest while behind him. When I was drafting it felt like I was being pulled along, sometimes I didn't even have to turn the cranks to keep up!

I’ve never drafted. The first group ride I ever took was last fall. 800 cyclists with the State governor for 2 days - 120 miles. They told us to be prepared for 13 mph. (slower up hills). I was concerned that I could keep up that average over hilly terrain.

Well the ride was fantastic! I saw nobody drafting. It seems all of us were averaging 14 to 15 mph and we keept arriving at the next rest stop ahead of schedule. I climbed hills I didn’t realize I could and I kept a pace I never dreamed I was capable of keeping. I don’t remember looking at my computer at all during the ride - too much to think about, look at and talk to. At the end of each day I felt great! At the end of the 2 days my average was 14.8 mph (and that included a slow 3 hour ride through Philadelphia.)

Group ride are great! Have fun!

Well it depends. You can go a lot faster in a paceline or a group if the following 2 apply:

1) you are going fast enough for wind resistance to be a factor

2) and you get in close enough to get into the other rider's slipstream.

Solo, I often cruise at 18-22 mph. I went on a century and the fast group formed a peleton and it felt as if I was not working as hard as I did solo. When I things got slow, I would glance at my speedometer and it generally read 25+ mph. I ended up aveaging 24 mph for 65 miles (and that included slowing and stopping at a few lights).

The problem is that riding in high speed groups can be dangerous. You have to trust the person in front of you to a) be predictable and b) not do something stupid. I have had 2 bad crashes cycling and they have both been in high speed groups and were caused by someone else's mistake (if you don't count my relying on them not to make a mistake a mistake). So this is a practice that is very much do at your own risk.