I will tell you that I averaged 2MPH faster from one day to the next. Going from knobbies to slicks on my morning training rides. There was no question on how much nicer it was to be on some nice tires. I could just coast down most hills that I was having to pedal down to maintain my speed.
Now if they are saying you could gain 3-4mph going from a mtb to a road bike, I would almost have to agree. That is about what happened to me when I switched. I picked up almost 2mph on my rides going from my MTB (with slicks) to my current road bike (Jamis Nova with slicks).
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Reverend Dr. Jay
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