My wife got me a bike at Walmart bike and I want some help upgrading the components. It is a Schwinn 26" I am 50 years old and it is my first bike since I was a kid. I think it is a good starter bike, but I really want to put together a bike one part at a time, the frame being the last part and moving all the components over to the new frame. I have being running for a while, since I went into the Army in 1977 and have run a couple marathons and want to run my first triathlon in May and want to use this bike with a few upgrades, (new chainwheels ans cassette) for starters and could use some help. I am thinking about joining a bike club with a bike shop to help, but want all the help I can get. Thanks