Originally Posted by
koala logs
I would think that anyone with 17 lb bike would have low rolling resistance tires on them already.
That chart was made a few years ago, comparing the very good Conti 4000 with the (then new) even slightly better Conti 5000. The moral of that chart is that even small improvements in Crr can matter more than weight on fairly steep climbs -- you have to get to really steep before 100g in mass savings matters more than even the tiny improvement between the Conti 400 and 5000.
Originally Posted by
rm -rf
Two full Camelbak 24 ounce water bottles are 1600 grams. It would be interesting to use opaque bottles in a blind test climb, either empty or full. Is it immediately obvious, or extremely subtle?
I've done a test like that to validate measurements of Crr. I'm sort of a perceptual dullard: some changes I can feel, others I can't. Doing blind tests sometimes helps me sort through when and whether my perceptions are off. That said, for me, I can measure the difference in drag from an additional kg of mass but I'm not sure I could feel it during the test--often during tests, I have so many other things on my mind that perceived exertion is kind of blunted.
[Edited to add] "Can you feel the difference?" is often not as reliable a metric as we'd want. Years ago I used to ride on stiff frame skinny tire bikes, and they felt fast fast fast. However, stopwatches and speedometers are pretty reliable, and they reliably showed that a bike and tires that "felt" slower was actually faster. I had been perceiving "chatter" as fast and "smooth" as slow.
Not that smooth is always faster: sometimes smooth turns out to be slow. So I try to measure rather than rely on feelings. As I said, I'm a perceptual dullard.