Originally Posted by tjspiel

I'll let you know when I can track down numbers for rim and tire weights. Comparing my Specialized RockHopper with stock wheels and tires to my Specialized Allez with stock wheels and tires will I'm guessing favor the road bike. The wheel diameter (including tires) of the two bikes is almost the same when I eyeball them and I would guess the substantially heavier MTB tire will tip the balance toward the Allez. It's admittedly skewed though because I doubt many roadies commute with 23's. On the other hand the stock rims on the Allez are on the hefty side for a modern road bike.

We'll see.