geoffreydean wrote:
"Savings from a wheelset, tires, chain lube, ceramic bearings, aero helmet and the like are usually more like 2 or 3 watts, assuming the tech is a real success. Replacing a pair of butyl tubes in your tires with a pair of latex tubes – if you’re not running tubeless – is worth 2 to 3 watts tops." Savings from a wheelset is only 2 or 3 watts?
Aero helmet saves only 2 or 3 watts?
I thought those two items were major aero upgrades.
they're all major upgrades but how major depends on upgrading from what to what. canyon isn't claiming that their new speedmax takes 9 fewer watts to pedal at the same speed as your schwinn varsity, but it's a 9w savings over the bike that's won the last few hawaiian ironmans. so...
aero wheels don't save 2 or 3 watts over non-aero wheels. apples-to-apples would be: how much do you gain with the zipp 858 over the 808? it's like that.
aero helmet. again, we're not talking aero helmet versus skid lid, but the latest aero helmet over the aero helmet that came before it, or a reasonably aero general use road helmet. we're not talking a super duper space aged chain lube over a dry chain, but over an appropriately lubricated chain lube. ceramic bearings versus versus what would go in a reasonably high-end derailleur. real world upgrades.
now, latex tubes, this is going to get me into the dutch. but again, it depends on what butyl tubes we're talking about. this is a race application. when BRR tested this, i think what they found is that we're looking at a 2w savings, maybe 3w, maybe 4w? over a typical race application butyl tube. like a conti race. if i'm wrong and somebody has the link to that test (from maybe 5 or 6 years ago?) please disabuse me of my error.
Dan Empfield
aka Slowman