That’s the matter under discussion: whether there’s energy storage or power dissipation. If it’s for example, 1.6 joules (watt-seconds) of energy stored in the crank, and you’re riding at 320 watts, that’s 0.05 seconds of power wasted, assuming you have full force on the crank when you cross the line. I’m not worried about that, as I’m not a…[Read more]
Thanks, Jason! This would perhaps be a good test for FrictionFacts, who have the best publicly available testing of drivetrain power efficiency at present. Unfortunately the crank is part of an integrated system, including frame and rider, so I wonder how relevant a bench test would be. Despite that, it would be better than nothing, and…[Read more]
Ah — good to connect real names with aliases. Your posts on Weight Weenies are certainly excellent.
It’s a funny difference in perspective: you say “only 1.6 watts” but I see “a whopping 1.6 watts”. That’s around 5 seconds up Old La Honda road, as much effect as 350 gram difference in crank mass.
By “heat” I am referring to…[Read more]
Excellent! I’m glad to see the crank test is active. I look forward to new cranks.
The one issue I have is with the assumption that all elastic strain energy is dissipated as useless heat. There’s one obvious relaxation path, and that’s to drive the chain, which represents a power delay but not an energy loss. I suspect the vast majority of…[Read more]