Respectfully, your site is not as usable as BikePedia on a laptop computer. Here are some suggestions:
Let me change the model year without having to select the model again. BikePedia has quick links for this, so I know right away what other years there are.
Have the comparison tool default to something smart, such as the same year and manufacturer, rather than starting the second bike totally blank.
Add some sort of filtering to help people find bikes they might want ("about three years old, MTB, Shimano XT or similar").
Let me change the model year without having to select the model again. BikePedia has quick links for this, so I know right away what other years there are.
Have the comparison tool default to something smart, such as the same year and manufacturer, rather than starting the second bike totally blank.
Add some sort of filtering to help people find bikes they might want ("about three years old, MTB, Shimano XT or similar").