The SIGs are spring training series designed to help people learn group riding skills, and build up strength, speed, and endurance before the summer season. The numbers are the target crusing speed that each group aims to acheive by the end of the series. So, the B18 SIG will, ideally, be riding 18 miles on the flats by the time the series concludes in a couple of weeks. The A,B,C, is used for all rides (not just sig series) and generally is an indicator of the intensity of the ride, A rides being the fastest paced with minimal stops. Hope that helps. I highly recommend the SIGs (too late for this year) as a way to improve skills, have fun, and get to know a lot of people. But that can all happen on regular group rides as well.

For further information, look on the Rides page of this website. There's a full description of how we designate rides. Also, on the right side of that page is a description of the self-classification ride that will help you determine what's the appropriate category for you.

As Colleen explained, each SIG is a training series that requires a commitment to the full series. Those rides cannot be joined by new people once the series has started. All our other rides are open to anyone seeking to ride in that category at that speed.