Dura-Ace R9200

[tjvirden]

FSA did found a suitable partner, they just didn't took the financial commitment to order proprietary SKUs in large amounts.

Regarding "new and different" designs, the team that originally designed the FSA system (European, not Tiso), sold it to another taiwanese company until it finally landed on FSA's lap. They have a linear system prototyped, no linkages. You don't use linkages in a CNC Mill or lathe after all...

Well, that's a pretty good illustration of just how difficult it is actually becoming a player in terms of retail sales.

There's certainly plenty of effort in developing 'new' things - New Motion Labs, Classified and Rein4ced (!) spring to mind - but, in my view, most of that happens because the designers don't understand why the current stuff is as it is [Classified hub, okay I can see it as a niche product]. Put some wheels on a CNC machine tool and see if it makes a great bike

Shimano have made many mis-steps in product design, but - so far - they have recognised problems and quickly updated the products. They are big enough (and profitable enough) to be able to get away with that - perhaps that will change one day. I'm definitely expecting R9200 to be 'nothing special' because there's been so much upheaval in the last 5 years (in bicycle world), but the Dura Ace after might be really quite something and not so far off either.

[RDY]

I don't think it will be special at all. The two main improvements will be calipers (supposedly) that will be easier to bleed and prevent rub, and wireless front end. From what I've heard, they're retaining Hollowtech and cassette bodies pretty much unchanged ... so after years of it, we'll still have delaminating cranks and cassette body failures.

[Ritxis]

August 22 in shops? The deadlines said long ago will be met.

[pdlpsher1]

If Shimano is sticking to Hollowtech I wonder if they are also sticking to hollow chainrings. One gripe I have with the current Dura Ace is noise. The hollow structure within the chainring amplifies chain clatter especially when cross chained on the big ring. This is akin to how many acoustic music instruments work. Of course the small ring has no noise issues because it has no hollow structure. There are times when I'm doing an extended climb with a slight big ring cross chaining (3rd cog counting from the biggest cog). I'd be saving watts with big ring cross chaining as compared to a small ring cross chaining. But the noise is quite loud and annoying so I usually just end up riding on the small ring with a cross chain. I have other bikes with solid big rings (i.e. GRX) and I can cross chain on the 2nd cog counting from the biggest cog and the drivetrain is still silent compared to the Dura Ace. Hollowtech on the crank arms is OK but I'd rather have solid chainrings, preferably with direct mount spiders or one-piece direct-mount chainring/spiders.

[slake21]

If Shimano is sticking to Hollowtech I wonder if they are also sticking to hollow chainrings. One gripe I have with the current Dura Ace is noise. The hollow structure within the chainring amplifies chain clatter especially when cross chained on the big ring. This is akin to how many acoustic music instruments work. Of course the small ring has no noise issues because it has no hollow structure. There are times when I'm doing an extended climb with a slight big ring cross chaining (3rd cog counting from the biggest cog). I'd be saving watts with big ring cross chaining as compared to a small ring cross chaining. But the noise is quite loud and annoying so I usually just end up riding on the small ring with a cross chain. I have other bikes with solid big rings (i.e. GRX) and I can cross chain on the 2nd cog counting from the biggest cog and the drivetrain is still silent compared to the Dura Ace. Hollowtech on the crank arms is OK but I'd rather have solid chainrings, preferably with direct mount spiders or one-piece direct-mount chainring/spiders.

I always wondered why the small ring was quieter. Never thought of that.

[XCProMD]

FSA did found a suitable partner, they just didn't took the financial commitment to order proprietary SKUs in large amounts.

Regarding "new and different" designs, the team that originally designed the FSA system (European, not Tiso), sold it to another taiwanese company until it finally landed on FSA's lap. They have a linear system prototyped, no linkages. You don't use linkages in a CNC Mill or lathe after all...

Well, that's a pretty good illustration of just how difficult it is actually becoming a player in terms of retail sales.

There's certainly plenty of effort in developing 'new' things - New Motion Labs, Classified and Rein4ced (!) spring to mind - but, in my view, most of that happens because the designers don't understand why the current stuff is as it is [Classified hub, okay I can see it as a niche product]. Put some wheels on a CNC machine tool and see if it makes a great bike

Shimano have made many mis-steps in product design, but - so far - they have recognised problems and quickly updated the products. They are big enough (and profitable enough) to be able to get away with that - perhaps that will change one day. I'm definitely expecting R9200 to be 'nothing special' because there's been so much upheaval in the last 5 years (in bicycle world), but the Dura Ace after might be really quite something and not so far off either.

I quite disagree when you say “they have recognised problems”. They honour their guarantees but insist in concepts that have proven problematic or even technical cul-de-sacs. A couple of those are contributing very substantially to the current state of affairs.


Skickat från min iPhone med Tapatalk

[tjvirden]

You're right that they've tried to introduce all sorts of stuff that hasn't worked well and I completely agree that there are issues with some of the current stuff as well as technical cul-de-sacs - they're very far from perfect! However, I can point to a variety of parts that they have corrected quickly. They never admit to faults in public, but stuff does get improved when it doesn't turn out to work well enough in the field. Think bottom bracket/crank attachment, hubs, cassettes, STI's.

[TwiggyForest]

If Shimano is sticking to Hollowtech I wonder if they are also sticking to hollow chainrings. One gripe I have with the current Dura Ace is noise. The hollow structure within the chainring amplifies chain clatter especially when cross chained on the big ring. This is akin to how many acoustic music instruments work. Of course the small ring has no noise issues because it has no hollow structure. There are times when I'm doing an extended climb with a slight big ring cross chaining (3rd cog counting from the biggest cog). I'd be saving watts with big ring cross chaining as compared to a small ring cross chaining. But the noise is quite loud and annoying so I usually just end up riding on the small ring with a cross chain. I have other bikes with solid big rings (i.e. GRX) and I can cross chain on the 2nd cog counting from the biggest cog and the drivetrain is still silent compared to the Dura Ace. Hollowtech on the crank arms is OK but I'd rather have solid chainrings, preferably with direct mount spiders or one-piece direct-mount chainring/spiders.

Hollow chainrings allow for the rings to be stiff but light by increasing the cross section of the chainring but not the amount of material. From an engineering perspective it's a good design (barring the extra noise). I would be surprised if they went away from it.

[TobinHatesYou]

Hollow chainrings allow for the rings to be stiff but light by increasing the cross section of the chainring but not the amount of material. From an engineering perspective it's a good design (barring the extra noise). I would be surprised if they went away from it.

Stiff and light is great, but the problem with Hollowtech is bond strength since they haven't figured out how to make those components a single piece.

[ChiZ01]

Stiff and light is great, but the problem with Hollowtech is bond strength since they haven't figured out how to make those components a single piece.

they know how, 105 crank arm are hollow forged, aka a single piece, they just don't know or maybe too expansive to make forged crank light weight. Probably cheaper to just go full carbon like SRAM

[TobinHatesYou]

Probably cheaper to just go full carbon like SRAM

Shh... don't wake him.

[pdlpsher1]

I like 105's design better. Non-hollow large ring and spider. Of course it's heavier but I'd rather have weight than noise.

[Maddie]

Remind me of Porsche 935 turbofan wheels

[XCProMD]

Stiff and light is great, and making thin, hollow structures to achieve such objective is a great idea. Moment of inertia, Steiner theorem and all that.

Until fatigue is considered.

Then things start to get complicated. Generally a higher moment of Inertia results in a reduced average stress level, and that allows for thin shell structures. But with thin shell structures it is important to pay attention to stress builiding up very quickly around features that disturb the tension flow. Another important thing to consider is stress reversing, this is, a part of the structure going from tensile stresses to compresive ones or the other way around, as that makes for a much more difficult stress range and stress history to handle.

All this is not dificcult to simulate on a computer by competent engineers.

But.

It is extremely important to have into account the variances in the potentially stress rising features that the tolerances and deviations in the manufaturing process create. One typical example is welds, more specifically weld start-stops and weld bead toes and roots. That's why the IIW gives FAT values for weld configurations and details.

There are also FAT values for material edges.... it is important to understand what is the true higher Rz value that your process will create. Can you measure that or do you have aprocess that can't produce a value above a certain level?

Glues are very often usen in shuoulders that are close to edges... depending on the joint configuration the edges can be quite stressed around some specific features... and depending on the joint configuration the bonded joint can be submitted to stresses is is not designed to withstand when there's a defect or crack start that generates a stress riser. Glue- shear- tensile stresses.... is the bonded joint fail safe?

[robbosmans]

Shimano drivetrains are louder, R8000 and R9100 especially, more to do with chain cassette. A 12 spd XTR chain can quite things down a bit, I don’t think the chainrings have anything to do with that.