Classified hub - Is this the new big thing?

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crlincoln
Posts: 157
Joined: Sat Dec 08, 2018 7:42 am

by crlincoln

I’ve decided to go down the classified route for next bike, currently in build at LBS. Based on ENVE Melee and ENVE wheel set.. with SRAM setup.

I really like the concept and willing to invest in it. I like SRAM, but hate their FD.

I’ve got some big Alps riding later this year, so will be interesting to see how I get on…

Sometimes you have to take a punt/risk and see how it goes…


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by Weenie


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TobinHatesYou
Posts: 12457
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

BigBoyND wrote:
Sat Feb 25, 2023 7:35 am

The 16t jump on Shimano is fine for me. I would prefer 17t or 18t, though. The AXS 13t just seems like an idiotic way to increase tooth jumps on the cassette.

Couple reasons for my views:
1. I shift the rear hundreds of times for each FD shift so I'd rather have small jumps where I shift more often. I'm in the small ring only if I almost run out of range on the cassette.
2. I don't "dump" that many gears at once. Before an FD shift, cadence starts to slow (or speed up) until it's near the end of the comfortable cadence range, and then it shift close to the other end. In reality, I'm shifting maybe 2 gears in the back after an FD shift. If I had to shift 3-4, I wouldn't mind, if it meant having a tighter cassette for the same range.

Going to a 13t jump in front has nothing to do with increasing the range in back. The 10t cog achieved that. Officially AXS supports only 1t more than a Shimano 12spd road RD.

A SRAM 10-33t cassette has a 330% range via a 23t difference.
A Shimano 11-36t cassette has a 327% range via a 25t difference.
A SRAM 10-36t cassette has a 360% range via a 26t difference.

SRAM bumped down to a 13t jump in front in order to keep compensation shifting to a minimum while still having equivalent range thanks to that 10t cog.

BenCousins
Posts: 1367
Joined: Thu Apr 23, 2015 11:46 am

by BenCousins

willing to invest in it
How much stock are you getting for buying one hub?

pmprego
Posts: 2513
Joined: Mon Jan 21, 2019 3:16 pm

by pmprego

I see a lot of people must ride with car support behind them. I imagine people designing a product and thinking about all those guys that drive with car support behind them.

Very nice and poor me that go out alone or with mates and we take our spares.

BigBoyND
Posts: 1350
Joined: Mon May 31, 2021 1:51 am
Location: Berlin, DE

by BigBoyND

TobinHatesYou wrote:
Sat Feb 25, 2023 10:31 am
BigBoyND wrote:
Sat Feb 25, 2023 7:35 am

The 16t jump on Shimano is fine for me. I would prefer 17t or 18t, though. The AXS 13t just seems like an idiotic way to increase tooth jumps on the cassette.

Couple reasons for my views:
1. I shift the rear hundreds of times for each FD shift so I'd rather have small jumps where I shift more often. I'm in the small ring only if I almost run out of range on the cassette.
2. I don't "dump" that many gears at once. Before an FD shift, cadence starts to slow (or speed up) until it's near the end of the comfortable cadence range, and then it shift close to the other end. In reality, I'm shifting maybe 2 gears in the back after an FD shift. If I had to shift 3-4, I wouldn't mind, if it meant having a tighter cassette for the same range.

Going to a 13t jump in front has nothing to do with increasing the range in back. The 10t cog achieved that. Officially AXS supports only 1t more than a Shimano 12spd road RD.

A SRAM 10-33t cassette has a 330% range via a 23t difference.
A Shimano 11-36t cassette has a 327% range via a 25t difference.
A SRAM 10-36t cassette has a 360% range via a 26t difference.

SRAM bumped down to a 13t jump in front in order to keep compensation shifting to a minimum while still having equivalent range thanks to that 10t cog.
You need to look at range as a whole. Big-small to small-big. For the same drivetrain range, AXS requires bigger % jumps in the rear.

The tradeoff for fewer compensation shifts is larger jumps, is greater gearing overlap between big ring and small ring. This goes for any given top and bottom gearing you need.

TobinHatesYou
Posts: 12457
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

BigBoyND wrote:
Sat Feb 25, 2023 11:22 am

You need to look at range as a whole. Big-small to small-big. For the same drivetrain range, AXS requires bigger % jumps in the rear.

The tradeoff for fewer compensation shifts is larger jumps, is greater gearing overlap between big ring and small ring. This goes for any given top and bottom gearing you need.

You don't get it.

10-11-12 = 10%-9.1%
11-12-13 = 9.1%-8.3%

The jumps are larger in percentage because of the 10t cog. It's got nothing to do with the difference up front.
And because smaller rings are used, the absolute changes in gear-distance are not far off.

The decision to go with a 13t jump is driven by the use of the 10t cog. Going 13t up front didn't drive any changes in itself.

Lina
Posts: 1060
Joined: Sat Sep 01, 2018 9:09 pm

by Lina

It's possible to operate the hub with Di2 shifters right? But does it work with syncro shift. That could make syncro shift an interesting proposition.

BigBoyND
Posts: 1350
Joined: Mon May 31, 2021 1:51 am
Location: Berlin, DE

by BigBoyND

TobinHatesYou wrote:
Sat Feb 25, 2023 12:50 pm
BigBoyND wrote:
Sat Feb 25, 2023 11:22 am

You need to look at range as a whole. Big-small to small-big. For the same drivetrain range, AXS requires bigger % jumps in the rear.

The tradeoff for fewer compensation shifts is larger jumps, is greater gearing overlap between big ring and small ring. This goes for any given top and bottom gearing you need.

You don't get it.

10-11-12 = 10%-9.1%
11-12-13 = 9.1%-8.3%

The jumps are larger in percentage because of the 10t cog. It's got nothing to do with the difference up front.
And because smaller rings are used, the absolute changes in gear-distance are not far off.

The decision to go with a 13t jump is driven by the use of the 10t cog. Going 13t up front didn't drive any changes in itself.
Lol you say I don't get it while missing my point about system range. I'm not talking about the 1t jumps (which are also bigger with Sram, as you pointed out). I'm talking about the fact that a smaller range at the front (13t vs 16t) requires greater range at the rear. The greater range at the rear requires greater jumps (more teeth) in the middle and top of the cassette.

If you want a 1:1 low gear and a 4.6:1 high gear, for example, these are your options:
Shimano 50/34 with 11-34
Sram 46/33 with 10-33

These are the jumps on the cassette:
Shimano 9.1%, 8.3%, 7.7%, 7.1%, 13.3%, 11.8%, 10.5%, 14.3%, 12.5%, 11.1%, 13.3% (ave. 10.8%)
Sram 10.0%, 9.1%, 8.3%, 7.7%, 7.1%, 13.3%, 11.8%, 10.5%, 14.3%, 16.7%, 17.9% (ave. 11.5%)
Last edited by BigBoyND on Sun Feb 26, 2023 7:39 am, edited 1 time in total.

User avatar
Miller
Posts: 2764
Joined: Thu Sep 21, 2006 8:54 pm
Location: Reading, UK

by Miller

crlincoln wrote:
Sat Feb 25, 2023 9:30 am
Sometimes you have to take a punt/risk and see how it goes…
This is true. Be sure to report back on your experience with this build.

User avatar
Lelandjt
Posts: 836
Joined: Tue Jan 19, 2016 7:10 am

by Lelandjt

elmtree wrote:
Fri Feb 24, 2023 9:27 pm
Lelandjt wrote:
Fri Feb 24, 2023 8:52 pm
hansotto089 wrote:
Fri Feb 24, 2023 7:01 pm
Does anybody know how the Classified Powershift plays with the Di2 Semi-Synchro shift?
It can't be shifted under ANY load so I wouldn't want to be caught by a surprise automated "front" shift.
It can be shifted to to 1000w iirc. I think it's better than front derailleurs for shifting under load
Huh, every other planetary gear hub can't be shifted under load. I wonder what they did differently.

aeroisnteverything
Posts: 893
Joined: Fri Aug 24, 2018 4:43 pm

by aeroisnteverything

Lelandjt wrote:
Sat Feb 25, 2023 5:48 pm
elmtree wrote:
Fri Feb 24, 2023 9:27 pm
Lelandjt wrote:
Fri Feb 24, 2023 8:52 pm
hansotto089 wrote:
Fri Feb 24, 2023 7:01 pm
Does anybody know how the Classified Powershift plays with the Di2 Semi-Synchro shift?
It can't be shifted under ANY load so I wouldn't want to be caught by a surprise automated "front" shift.
It can be shifted to to 1000w iirc. I think it's better than front derailleurs for shifting under load
Huh, every other planetary gear hub can't be shifted under load. I wonder what they did differently.
Interesting, no? I think there is something clever inside - I suppose we won't soon find out what.

But shifting under load is for real. There are GCN videos of it, reviewers mention it and it's a key part of their marketing pitch - under load and virtually instantaneous.

Lina
Posts: 1060
Joined: Sat Sep 01, 2018 9:09 pm

by Lina

Lelandjt wrote:
Sat Feb 25, 2023 5:48 pm
elmtree wrote:
Fri Feb 24, 2023 9:27 pm
Lelandjt wrote:
Fri Feb 24, 2023 8:52 pm
hansotto089 wrote:
Fri Feb 24, 2023 7:01 pm
Does anybody know how the Classified Powershift plays with the Di2 Semi-Synchro shift?
It can't be shifted under ANY load so I wouldn't want to be caught by a surprise automated "front" shift.
It can be shifted to to 1000w iirc. I think it's better than front derailleurs for shifting under load
Huh, every other planetary gear hub can't be shifted under load. I wonder what they did differently.
Because it's got 1:1 and a lowrange gear. I'm pretty sure they just lock the entire hub into one when going to the 1:1 ratio. So it's not actually changing gears in the planetary. That's also how they will have 100% efficiency in the 1:1 ratio.

pmprego
Posts: 2513
Joined: Mon Jan 21, 2019 3:16 pm

by pmprego

They say it's able to shift either side under load. Not what you are suggesting - Lina

Lina
Posts: 1060
Joined: Sat Sep 01, 2018 9:09 pm

by Lina

pmprego wrote:
Sat Feb 25, 2023 7:48 pm
They say it's able to shift either side under load. Not what you are suggesting - Lina
Unless there's some sort of a freewheel so that the planetary is engaged the entire time, just not connected to the rest of the hub when on the big ring. So all it changes on gear changes is disengage the hub locking and engage the planetary when changing to low range. And vice versa when changing to the big ring. Something similar is how I'd do it. They pretty much have to lock the hub for the 1:1 ratio because that's the only way they get 100% efficiency on the big ring. And they pretty much have to have the planetary engaged the entire time to be able to change under load.

by Weenie


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User avatar
Miller
Posts: 2764
Joined: Thu Sep 21, 2006 8:54 pm
Location: Reading, UK

by Miller

I've had a 10 minute ride on a bike with a Classified hub, one of their demo bikes. Shifting is more or less instantaneous and there is no requirement to alter your pedalling while shifting.

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