The more I thought about my options, the more confused I got. I have ruled out the option of buying a bike from Craigslist or something like that because it's really important to get a bike that fits me right (if I'm going to pay anything for it). I went to the bike store where Trey works just to look. And this is what I found:
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I rode a few different bikes around the parking lot and the guy adjusted the seats of each bike a few times for me to try them out. The one is this pictures is a Specialized Dolce bike and it was the one that worked the best for me. I got on the indoor trainer just to pedal for a while and see how it feels. While I was doing that, Trey walked in! I was so glad to talk to him about my options for bikes.
Depending on how important this is and whether or not I can really afford to do it, I should probably go ahead and buy a pretty nice bike. Not top of the line or anything, but something that will last a long time and be easy to ride in this triathlon or any others I may decide to do in the future.
I have a few days to decide because the one I was riding today has really already been sold to someone else and is waiting to be picked up. They have another one coming in on Tuesday that I could get. I just need to make a decision.
The other decision is about what to do with the old bike. I don't know if anyone else would want it. It works fine if you don't try to change gears too much. It's probably not worth it though. I'll figure out something to do with it.