2020 Aethos Sub UCI weight Specialized.

[FlatlandClimber]

There are several studies showing that 1x drivetrains are generally more inefficient than 2x drivetrains, with there only being a very small Sweetspot where 1x makes sense (for on road chain efficiency).
However, the point I am making is not that the average person will spend <10% in the smallest gear (a point that can also be made about SRAMs 10t cog), but that she likely spend 90%+ of the climb in that gear. It was a 13% average climb after all...

[BigBoyND]

There are several studies showing that 1x drivetrains are generally more inefficient than 2x drivetrains, with there only being a very small Sweetspot where 1x makes sense (for on road chain efficiency).

Which studies? How many watts?

FrictionFacts is reputable and they say 1W for smallest cog and 1.4W for cross chaining. During the uphill it's 1.4W and downhill its 2.4W (if the rider is even pedaling at that point). That's nothing.

And when I say FrictionFacts, I mean Jason Smith, founder of Friction Facts and Chief Technology Officer for CeramicSpeed. If you have a better source, please do share.

[Lina]

There are several studies showing that 1x drivetrains are generally more inefficient than 2x drivetrains, with there only being a very small Sweetspot where 1x makes sense (for on road chain efficiency).
However, the point I am making is not that the average person will spend <10% in the smallest gear (a point that can also be made about SRAMs 10t cog), but that she likely spend 90%+ of the climb in that gear. It was a 13% average climb after all...

You're MASSIVELY overrating the inefficienies of both small cogs and crosschaining.

[PSM]

Is Durianrider registered on WW?

[FlatlandClimber]

What are we even talking about at this point? The bike was purpose built to be as fast as possible up that one super steep climb, and the focus was too much on low weight, while not focusing enough on:
- chain friction
- bio-mechanical efficiency
- traction related efficiency

One kg of added weight is around 5 Watts at the power and grade she was likely going at.
If half of that goes out the window for preventable chain inefficiency (she was doing around 330W, not 250W as tested - but yes, I overestimated the effect)
And likely significantly more goes out the window for tire slippage, both because of low cadence -> high torque (likely even forced to pedal out the saddle). And because of a questionable tire choice.
Biomechnacal inefficiency of low cadence are hard to quantify, but they sure are a thing.

Let's close this topic here. Who wants to continue discussing can open a new thread.
Back to Aethoses.

[BigBoyND]

"The chainline would have really been a much bigger factor."

"It's just 1.5W"

"What are we even talking about at this point?... Let's close this topic."

Lol

We just corrected your overstatement on drivetrain efficiency to keep it from being perpetuated. Nothing about the 10 other random things like tire slip.

[FlatlandClimber]

"Random things" - that was my initial critique on the bike and you just chose to respond to a specific one of them. I never put a number on the specific thing you responded to, so how did you "correct" it?

Your specific response was actually pretty random talking about spending less 10% of the time in the smallest cog and efficiency of chainline on descents. We were talking about one specific hill climb bike on one specific hill, not about just all round riding.

[robeambro]

I'm going to take the discussion away from the polemics with a daft question.
What's the height of the stock headset cap supplied with the Aethos, and in case that's taller than 10mm, can it be replaced with something in the region of 8-10mm? It's probably a silly question but this is what happens when your current bike has "mandatory spacers", you are not used to having the chance to tinker your position with headset caps.

[UpFromOne]

Just use a much lighter aluminium cassette, then you wouldn't have to chop cogs.
Or better yet, chop an alu cassette (the ones with splines all across).

And in general, I don't get not using <800g wheels, but then such things as chopping the bars.
All those bikes could be made lighter with better component selection.
So the "money no object" motto is misapplied.

[garbageman]

I'm going to take the discussion away from the polemics with a daft question.
What's the height of the stock headset cap supplied with the Aethos, and in case that's taller than 10mm, can it be replaced with something in the region of 8-10mm? It's probably a silly question but this is what happens when your current bike has "mandatory spacers", you are not used to having the chance to tinker your position with headset caps.

The bearing cover is 10mm.

[robeambro]

I'm going to take the discussion away from the polemics with a daft question.
What's the height of the stock headset cap supplied with the Aethos, and in case that's taller than 10mm, can it be replaced with something in the region of 8-10mm? It's probably a silly question but this is what happens when your current bike has "mandatory spacers", you are not used to having the chance to tinker your position with headset caps.

The bearing cover is 10mm.

Thank you, that's ideal!

[ckspark]

My Aethos Comp 10R 56cm naked teal fade frame. Bought a complete used bike, the 10R frame is not available in the UK and I can't afford the S works. Going to build as light as my budget allows.

Completely bare 704g

With fittings except hanger 735g

Fork uncut completely bare 306g

[robeambro]

My Aethos Comp 10R 56cm naked teal fade frame. Had to buy a complete bike as the 10R frame is not available in the UK and I can't afford the S works. Going to build as light as my budget allows.

Completely bare 704g
IMG_20211119_103814382.jpg

With fittings except hanger 735g
IMG_20211119_105031265_HDR.jpg

Fork uncut completely bare 306g
IMG_20211119_110742943.jpg

Wouldn't buying a complete bike and strip it set you back nearly as much as buying the S-Works frame? Iirc it's £5k for the Rival build - if you're lucky enough to sell groupset, wheels, etc, that would be maybe £1k at best. I'm asking as I've ended in the same conundrum and thought it was worth going for the latter.

[ckspark]

My Aethos Comp 10R 56cm naked teal fade frame. Had to buy a complete bike as the 10R frame is not available in the UK and I can't afford the S works. Going to build as light as my budget allows.

Completely bare 704g
IMG_20211119_103814382.jpg

With fittings except hanger 735g
IMG_20211119_105031265_HDR.jpg

Fork uncut completely bare 306g
IMG_20211119_110742943.jpg

Wouldn't buying a complete bike and strip it set you back nearly as much as buying the S-Works frame? Iirc it's £5k for the Rival build - if you're lucky enough to sell groupset, wheels, etc, that would be maybe £1k at best. I'm asking as I've ended in the same conundrum and thought it was worth going for the latter.

Yes agreed but I bought a barely used bike. Just pointing out that under the ballast is still a very light frame even on the cheapest Comp and is an option for anyone wanting to upgrade over time.
Why would I be lucky to sell the Rival groupset? It's sold out in the UK so obviously popular.

[robeambro]

My Aethos Comp 10R 56cm naked teal fade frame. Had to buy a complete bike as the 10R frame is not available in the UK and I can't afford the S works. Going to build as light as my budget allows.

Completely bare 704g
IMG_20211119_103814382.jpg

With fittings except hanger 735g
IMG_20211119_105031265_HDR.jpg

Fork uncut completely bare 306g
IMG_20211119_110742943.jpg

Wouldn't buying a complete bike and strip it set you back nearly as much as buying the S-Works frame? Iirc it's £5k for the Rival build - if you're lucky enough to sell groupset, wheels, etc, that would be maybe £1k at best. I'm asking as I've ended in the same conundrum and thought it was worth going for the latter.

Yes agreed but I bought a barely used bike. Just pointing out that under the ballast is still a very light frame even on the cheapest Comp and is an option for anyone wanting to upgrade over time.
Why would I be lucky to sell the Rival groupset? It's sold out in the UK so obviously popular.

Oh I didn't mean to be rude - just saying that selling stuff second hand can be a pain. And for sure, it's a valid frame. Apologies if it sounded the wrong way.