burnthesheep

Of course it won't, especially for anyone who isn't in the vast minority of folks who would ever benefit from such a thing.

The groupset makers aren't interested in making a straight chainline optimized, not very often shifted, single event use rear derailleur. In other words, they aren't interested in making a time trial rear derailleur optimized for folks who mostly do flat TT's and never shift gears.

The big wheel long cages don't shift as well. So that's a non-starter for them to make that compromise and make tooling and inventory for that. The 1/3 of a single watt or half a watt gained isn't worth the loss of shifting accuracy or speed to most users.

Don't forget, just because the use case being 99.99% irrelevant and meaning a groupset maker won't do it doesn't mean it isn't relevant to the .01% of folks. It's just the marketing push to sell product to folks who don't understand.

We agree here, I just don't agree on some of the rationales being provided. That's all.

TakingMyTime

I'll chime in. I've got some free time this morning.

I too am in the market for a new bike. If I was to be given the item it would be on my new bike in a heartbeat. I don't need it or believe it will improve my performance. But it would be on my bike as soon as I got home.

popeye

Sell it and buy a skinsuit, win win.

PeteHski

Who are those 0.01% of folks finding a real advantage? What is that advantage in objective terms? (I very briefly saw one report talking about 1W advantage and it didn't even state what the total reference power was). Sounds like it might just about break even against the extra weight and aero drag, lol.

Maybe someone can link to a proper independent study for interest sake?

GhostRider62

The 1 watt advantage was at 250 watts for a crappy bushing pulley. Less than 0.1 watts against steel bearing pulleys like Hawk. Around 0.3 watts against most pulleys like Dura Ace or Sram. Approximate numbers by memory. I would not be surprised if that huge OSP pulley costs 1-2 watts to the air at 40 kph.

The one claim that CS makes that contradicts other research is lower friction due to slacker chain tension. They claim 1-2 watt advantage due to lower chain tension IIRC. I'm not an ME, but having looked at it a few year ago, I came to the conclusion their claims were BS. If it was 2-3 watts, I would spend the money to be honest. I came to the conclusion that 80 dollar Hawk bearings were just fine when the stock SRAM pulleys wore out.

I wonder if there is a 5 year old British ME who has looked at these claims?

PeteHski

Fractions of a Watt would be pretty hard to verify in testing anyway. There's a lot of variables at play in a drivetrain.

GhostRider62

I would be curious to see if Hambini weighed in but not in the mood to listen to a 30-40 minute youtube of his at the moment.