Originally Posted by
nuke_diver
Can you explain what a Gear Chart is? I am not familiar with the term and how to do what if analysis using it. I'm sure my bike has a standard double because I do not recall any other options at the time
Here you go. Basically, you figure out the combinations you have now, and plug them in, then compare them to other combinations you might get for your old bike, or that are available on modern bikes.
http://home.earthlink.net/~mike.sherman/shift.html