The first mountain bikes were made out of steel, but that is not why we decided to make these. We chose steel because it offers the best combination of value, comfort, and resiliency of all the popular frame materials. Hardly any folks these days buy a steel frame as their first mountain bike. It's those who've ridden a while and have tried aluminum and full suspension -- who come a knockin'. We do 29ers, 26ers, and 650B'ers.