Next gen Dura Ace

[Jz91]

Maybe it's purely my wish alone but can we get rid of 53/39 and replace it with wider range front rings?
IMO, it should have been
50/34, 52/36, 54/38, 56/40.

Actually, SRAM's smaller gaps between the chainrings are something which IMHO make more sense. If you have a close ratio cassette like 10-28 or say 11-30 you can have 1T jumps over a very wide range, but with 16T chainring gaps (especially 50x34) there are bigger gaps in the middle, right where I don't want them.

Some of the e.dubied cassettes linked to above do indeed look very useful, more so than the stock Shimano options.

Sram and Campa gearing makes sense only for touring purposes and seem to be forcing off-road solitions on road. Whilst it might work sometimes, it is not always the ideal solution.

What's the point of having a 50 as largest chainring? And that is the biggest...imagine a 48 or 46...It only forces people to be constantly in the 10-11 cog when riding in a bunch.

Proof is pros have requested old style chainrings. Difference with us though is that they can push a 40 plus inner chainring on any climb.

And as I poined out earlier sram's cassette as simialr jumps as the old 11sp 11-32 as they waste a cog to remediate to the small front chainring.

Campa might be even worse with the largest gearing combo being a 50-34...
It's not just about the range but the gears in between...just because there's a 10 cog doesn't mean people should be using gravel gears.

[cleanneon98]

I don't get the gripes with the gear overlap on the current Shimano, I quite like the way its set up with my 52/36 11-30. In my big flat/rolling ring I've got enough gearing to deal with small rises (albeit a bit crosschained) and not have to make the jump to the small ring. In my small climbing ring, I've got enough to go up an incline but also can deal with some of the little recovery valleys where the gradient eases off (again, crosschained) without switching to my big ring. Ideally I'd like a 54/38

Having SRAM on my MTB I can tell you that 10t is like pedalling through mud and with their biggest of the shelf road rings being 50/37 I'd be spending more time in the 50x10 than I care to.

[xiyuwang]

The cogs are not cold forged. A boron steel / titanium cold rolled sheet is out into a transfer press and submitted to different cutting/forming stages (hence “transfer”) until the final shape is acquired. Then the steel cogs go to an induction austenitizing furnace and are quenched to give them the hardness needed in service (Shimano=around 35 HRC bulk hardness) after that comes pickling (to remove the austenitizing/quenching scale) and final hot dip coating.


Skickat från min iPhone med Tapatalk

And this process is what gives shimano cassettes their toughness and durability. It seems to be a general consense that shimano has 'better' shifting than sram. If the CNC cassettes were so great, why wouldn't shimano at least make their dura ace cassettes this way? Because their stamping process may be cheaper to mass produce parts but the initial setup cost will be much more expensive than a CNC machined cassette and produces better quality.

That process does nothing to give toughness. Boron steel + quenching gives hardness, oftentimes at the expense of... toughness.

The way a cassette lets the chain go from a cog to another is related to cog design and phasing, but has little to do with the manufacturing technology as far as it allows for enough precission to accomodate the tolearnces needed by the design. Which stamping does in the case of HG / HG +/ Linkglide, as far as the tools are kept in good enough shape.

This doesn't preclude the fact that machining is a technology that allows for better precision / tighter tolerances. It can't be otherwise as the tools used for stamping are... machined. Any process can only be as good as the preceeding process is a mech engineering joke (yes we do humour too here and there).

As I said, coating is becoming critical. spacing is getting so tight and cog design so detailed that any undesired material accumulation during coating results on noise or worse.

I'm interested in comparing the different manufacturing processes for two high end cassettes like dura-ace vs sram. First, are you sure that a dura ace cassette would be hot dipped? That sounds more plausible for the lower end cassettes. I would think that a dura ace cassette would use a more controlled coating process that would not compromise dimensional accuracy.

Anyways, how would a CNC cassette wear wrt to a dura ace cassette? It seems to me like it would have a much higher wear rate and lose dimensional accuracy much quicker. My point is, why would shimano not use CNC for their high end cassettes if it produced a better product. Why is Shimano generally considered to be better at shifting. Is this related to the manufacturing process of the cassette. If CNC produces a higher precision and more dimensionally accurate cassette than what are the downsides? Are they better overall cassettes and again I ask why doesn't Shimano use this process.

It's not strange that Shimano is being greedy on DA as well, trying to cheap out as much as they can. If they already have an assembly line that can also make DA cassettes, they just won't spend extra money and time figuring out how to do CNC and later surface-treating the cogs correctly (or they might simply not have a deep knowledge base for this).

SRAM CNCs forged metal cylinders and probably applied surface treatment to ensure durability. I don't really see a durability concern on SRAM's high-end cassettes. But machining hard metal does cost a lot, e.g., feeding speed cannot be high and you need a lot of cooling compared to machining softer aluminum materials. This is likely why you see SRAM's high-end cassette is incredibly expensive. Shimano is pushing the precision limit of its own process, but as mentioned, the nature of Shimano's process is that it will be less accurate.

For head-to-head comparison, since Shimano and SRAM won't publish their manufacturing details, it cannot be reviewed technically. Maybe some published papers have mentions of it albeit being hard to read and extract information.

[satanas]

Sram and Campa gearing makes sense only for touring purposes and seem to be forcing off-road solitions on road. Whilst it might work sometimes, it is not always the ideal solution.

What's the point of having a 50 as largest chainring? And that is the biggest...imagine a 48 or 46...It only forces people to be constantly in the 10-11 cog when riding in a bunch.

just because there's a 10 cog doesn't mean people should be using gravel gears.

^ You obviously have a drastically lower cadence than I do - not everyone is the same(!). I would use 46x10 only rarely, on fast descents, and literally never on the flat. TDF footage suggests that in breakaways pros on Shimano are typically in 54x13-15 on the flat, but their speeds and wattages are way higher than most of us will ever achieve. Trying to ride the same gears "because the pros do" doesn't make sense to me; YMMV.

As for the gravel gearing comment, unless you're in the lead pack at a major race on easy terrain then 46/48 x 10/11/12/13 are going to be fairly pointless (or perhaps "aspirational") gears for many people. If your local terrain is steep and/or you do any bikepacking then more gears elsewhere are going to be way more useful. One can always coast on rough descents but in my experience coasting on climbs is less effective...

[Jz91]

Sram and Campa gearing makes sense only for touring purposes and seem to be forcing off-road solitions on road. Whilst it might work sometimes, it is not always the ideal solution.

What's the point of having a 50 as largest chainring? And that is the biggest...imagine a 48 or 46...It only forces people to be constantly in the 10-11 cog when riding in a bunch.

just because there's a 10 cog doesn't mean people should be using gravel gears.

^ You obviously have a drastically lower cadence than I do - not everyone is the same(!). I would use 46x10 only rarely, on fast descents, and literally never on the flat. TDF footage suggests that in breakaways pros on Shimano are typically in 54x13-15 on the flat, but their speeds and wattages are way higher than most of us will ever achieve. Trying to ride the same gears "because the pros do" doesn't make sense to me; YMMV.

As for the gravel gearing comment, unless you're in the lead pack at a major race on easy terrain then 46/48 x 10/11/12/13 are going to be fairly pointless (or perhaps "aspirational") gears for many people. If your local terrain is steep and/or you do any bikepacking then more gears elsewhere are going to be way more useful. One can always coast on rough descents but in my experience coasting on climbs is less effective...

My point was slightly different though. As soon as you gain some speed with a 46/48 chainring (standard SRAM Campa size) you'd be forced to run quite (too) often in the smallest cogs and have to soon revert to the 10 cog as a bailout gear. I see that this might not apply if you're on a solo endurance ride or cruising around in which cases they can be enough.

I don't know what type of rides you do but 46/10 is close to a 50/11 and it certainly doesn't take a pro to make full use of that gear also on fast flat situations like group rides. In the meantime though you're using/wasting a cog to compensate for such a small chainring.

Then there's also the matter of pedal efficiency and feel. For some people running small inner chainrings (Campa in particular) does not feel great even though the range on paper might be there.

At least SRAM has maintained decent inner size chainrings (not sure how much of this was intentional or driven by their technial limitations) but their cassette is not ideal for climbing given the jumps in the larger cogs. So again, they might claim they have the range of gears but the in-between is not really great.
Campa with their 45x29, 48x32, 50x34 are ludicrous and these are essentially the same as a shimano GRX (this was my reference to gravel ).

Again, if the goal is to serve the average weekend warrior or tourist then fine, but for the spirited amateur these gearings are not suitable IMO.

[BudhaNL]

48*14 @90rpm = 39.2 km/h, *11 = 49.89 km/h. Would that range not be suitable for your spirited group ride?

I ride solo 95% of the time (Netherlands so pretty flat ) and have changed from Ultegra 52/36 to Praxis 48/32 while keeping 11-30 (11-speed). I'll mostly be in 15-17 and have enough range for acceleration downhill or climbing.
On holiday in the French Alps this setup served me well.

Would it be difficult for Shimano to offer some more options in Dura Ace chainrings, e.g. 54-52-50-48 for large?

[wltz]

At least SRAM has maintained decent inner size chainrings (not sure how much of this was intentional or driven by their technial limitations) but their cassette is not ideal for climbing given the jumps in the larger cogs.

Arguably, larger gaps between the lowest gears don't matter that much on steep gradients, because gradients are very rarely constant and one's cadence or torque change all the time anyways. Where I ride in SE England, I spend orders of magnitude more time on 2-3% drags or descents than I do on steep stuff, so the 15-16-17t cluster is used a lot, and when it gets to the 19-22-25-28 cluster I'll pick the easier gear enabling faster cadence.

[TobinHatesYou]

Again, if the goal is to serve the average weekend warrior or tourist then fine, but for the spirited amateur these gearings are not suitable IMO.

SRAM has 43/30, 46/33, 48/35, 50/37, 52/39, 54/41, 56/43 for doubles and they have 1x chainrings from 30t to 68t.

I find that for flat/rolling road races a 56/43x10-33 is pretty ideal with five 1t jumps between six cogs. 52/39x10-36 would serve me well on my climbing bike. Shimano doesn’t have this kind of range because they are being stubborn about adopting the 10t cog.

[Hexsense]

^ If there were tighter gaps between the gears, then yes a wide-ish front range might make more sense. If you find larger gaps annoying (as I do when they're in my flat road range) then most of the current cassettes fail unless you're going at pro peloton speeds or have a fairly slow cadence. Range is now easy to come by, but close ratios at normal speeds are not.

Overlap between chainrings reduces the need for front shifting. Yes, Di2 et al makes this easier, but doing nothing is still easier than doing something. The wider the gap between the rings, the more rear compensating shifts are needed and these take time.

Bigger gaps between rings are fine for things like touring where you're not on your limit in a paceline and close ratios don't matter, but are not IME ideal for everything.

I see big ring as the main chainring. Small ring is range extender for climbing steep.
50t front and 27t rear (not cross chaining to 30t cog of the 11-30 which is currently smallest cassette Shimano offer for 12 speed) at 90rpm (some people can get away climbing at lower cadence than 90rpm but I don't) using 700x28mm tires is 13.4mph. Change to 52t front ring still make it 13.9mph.
I don't ride slower than 14 mph on flatland. So my small ring is only used when I climb significant gradient.
When I climb (speed dip below 14mph), I tend to go to small ring then finish the climb and shift to big ring right away at the top of the hill or during early part of the descend.
I never once have to shift front ring while riding in a fast paceline.

Of course, it wasn't always the case that we can stay on big ring for most of the time when the cassette was smaller. But as we progress to 12 speed, and cassette got larger, the large chainring can now take care of shallow hill. The small ring lost its job of handling small rolling hills. The shift to small ring is less frequent and when it happen, the climb is steep.

[Vee]

This sure doesn't look like the current gen DuraAce to me.... could it be!?

[Vee]

Another shot here:

[Vee]

Video of the pan down. https://a.storyblok.com/f/263970/x/2243 ... uced-1.mp4

[spdntrxi]

This sure doesn't look like the current gen DuraAce to me.... could it be!?

because it's look like a rendor to me.

[Vee]

This sure doesn't look like the current gen DuraAce to me.... could it be!?

because it's look like a rendor to me.

Colnago has plenty of renders on their site of the current dura ace. This is different.

[fizzaz]

It's a rendor. Look at that front brake caliper