Originally Posted by
BikeWNC
If the ride of the Tarmac is a bit harsh on a long ride, do what NealH does and use 25c tires instead of the standard 23c. It was a noticeable difference when I rode his SL3 bike over the weekend. When I test rode the SL2 bike I commented that I would have to use 25c tires with it because it was a bit harsh. As far as I could tell there was no discernible performance penalty going to the 25c tires. I suppose if you where on a solo breakaway there might be some aero loss but for most of us it won't make a difference. Even a few pros use a 25c rear tire for comfort. (Or get a Parlee Z4/5 lol)
Great point on the tires. Larger tires have greater aero drag, a couple of watts, which is not insignificant over a long distance. However, if the ride is better and fatigue is less then the power production will be better trumping any loss. Also, the Tarmac may have stiff wheels contributing to the harshness of the ride. Manufacturers match framesets, wheels and components to the expectation of the rider. In many cases, riders buying carbon fiber bikes want a stiff ride or they think they do. The bikes are tuned to this market.
The deciding factor for buying the Cervelo R3 was the design of the chain stays and seat stays to absorb shock. It does a very good job plus it will accommodate larger tires.
C'Fool, unfortunately, the best advice I can offer is HTFU
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