Originally Posted by
cafzali
Placebe effect is real, no doubt. But I also think a new, faster ride (or testing one) also prompts riders to up their effort, leading to real, measurable gains. They might go away once the test ride is over, but they're real nonetheless. I think it's increased effort that really produces the actual "upticks" from having a new bike as much, if not more, than any contribution from the materials themselves.
I think you're exactly right. You're simply describing the mechanism by which the placebo effect works.
And then people misattribute the actual cause of the increase. Hence, all the posts, "my average speed increased 2mph with my new bike."
The potential causes for increased speed with a new bike, in descending order of importance:
1) "New bike effect" i.e. I'm excited about my new bike, think its faster, and therefore it is (significant, but not repeatable);
2) changes in aerodynamic position (can be siginificant depending on the changes);
3) Difference in cycle computer calibration ( can be siginificant, but less likely with more use of GPS)
4) aerodynamic wheels/frame. (marginal, and likely only measurable if going to significantly more aero wheels, or aero frame)
5) lighter weight (diminimis on the flats, few seconds on climbs)
6) reduced friction. (truley diminimis, unless changing from high rollong resistance tires such as knobbies).
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