I'm another one who has biked the weight off, and I'm still in the process of doing it.
Before purchasing my bicycle, I started indoors on a stationary recumbent bike. I am still very heavy, with 89 MORE pounds to lose - BUT I've already lost 90 lbs!

Anyway...
After I lost the first 40 pounds, I treated myself to a regular bicycle. It was VERY DIFFICULT for me to ride at first, but I stuck with it. DH eventually bought one too. We both LOVE our bikes. I too cannot wait for some better weather for enjoyable rides, but at least I still have my indoor recumbent bike for those days. I plan to continue biking all the way to my goal and beyond because it's a blast!
Good luck to you!