I too am a type 1 and with the exception of subscribing to the specific diabetes newsgroups (which I do), I try to ensure that my lifestyle is as normal as possible. Sure, I have to make adjustments in some areas, but riding bikes is one activity where I can act much like everyone else. I'd not like to put myself into a specific corner, as being able to compete equally without anyone knowing what I have, is a testimony to the fact that I have my diabetes under control. Also, I don't think there is much that we with diabetes could share when it comes to riding. If it's just about rding, then we're part of something anyway. Anything that's diabetes related is also covered elsewhere. Linking the two would at best have minimal interest and I don't think there are that many of us to warrant a specific forum.
I fill myself with insulin 4x a day, blood test 4-6x a day, and apart from the usual hassles of injecting and testing, I've so far managed to live a very normal lifestyle. I don't think we need to label ourselves when it comes to riding.