As FBinNY said, tire volume is your friend. Run the widest tires that will fit in your frame. They will carry more weight, absorb more shock that would be going into the components, be more comfortable for you, have better traction and the only thing you'll be giving up is top end speed and aerodynamics. Since you're riding for fitness I don't think you could've done much better than the bike you chose.
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Originally Posted by
ahsposo
Ski, bike and wish I was gay.