Sy Reene

Easiest example are the DA cassettes with 5 of the cogs out of lighter, but quicker wearing, titanium (vs Ultegra). Save about 50-60 grams, and spend about $150-200 more to do so.

shelbyfv

I agree that 105 might be what you want. Best bang for the buck if you don't care about weight or aesthetics.

Maelochs

Different needs. With MTB, the higher-end stuff needs to be More durable, because riders are hitting everything faster and thus harder. Shifts are more likely made under load and at higher loads, pedals and cranks are getting bashed lees maybe, but harder, and everything is getting shaken and bashed with more force and energy.

On the road, less weight is absolutely acceptable in a lot of cases even if it comes with lower long-term durability----the oft-mentioned Ti cogs being the perfect example. No racer wants parts which break during a race, but it is assumed that if you want to win, you will pay not just the higher-up-front costs, but the annual replacement costs, for the cassette and anything else which might weigh less and wear faster---chains, for instance.

I am sure DA is just as durable per component on a race-to-race (or ride-to-ride) basis and Ultegra or 105, but not necessarily over a season. XTR on the other hand has to be at least as strong as XT but also lighter. Nobody wants to lose a race because of equipment failure due to underbuilding by the factory.

Koyote

I’ve seen a lot of this sort of talk in the thread, but I don’t recall anyone who has actual experience running both D/A and Ultegra. (Maybe I just missed it?)

I still have a nine speed Dura Ace cassette kicking around somewhere, and it has those titanium cogs. I ran it for a long time before pulling it off to go to different gearing, and never noticed any excessive wear.

I’ve worn through a 105 RD in less than two years, and had an Ultegra Di2 rear derailleur start to fail within one year. My 10 speed D/A RD is over 13 years old, on its second bike, and has at least 20-some thousand miles. Still works flawlessly.

If I were putting together a truly “money no object“ road bike, and I wanted to go with Shimano, it would be Dura Ace through and through. I wouldn’t need a thread to convince me.

Maelochs

I cannot imagine what I would need to do to a derailleur to break it with wear. Abuse, sure. I've done that. But just wearing it out? And the idea that 105 is weak trash compared to D/A .... not saying it didn't happen, but that is exactly the difference between "data" and "anecdote."

shelbyfv

Agree. Other than the Ti cogs, I've never seen anecdotal reports, much less evidence, that there is any difference in durability among the three Shimano "enthusiast" groups. I've worn out DA shifters, but I've done the same with 105 and Ultegra. I've never had any other component fail, from any of the three groups.

Kapusta

The notion that high end MTB components are expected last longer than high end Road components is absurd. You just made that up. If anything it is the opposite. Road components generally last longer than MTB components.

The point about the ti cassette cogs sounds good at first, but it is trivial for a few reasons:

• While technically Ti should wear a tiny bit faster, I've had many XTR caseettes with Ti cogs, and I never noticed them wearing out faster. If there was a difference, it was lost in the noise of the variations of all the things that wear cassettes out. But even if they do wear out a little faster,,,
• If someone IS worried about drivetrain wear items wearing out, then consider that you start seeing aluminum chainrings much farther down the food chain than DA. 105 rings are Aluminum. Are you going to suggest therefore that 105 is less robust than Tourney because Tourney uses steel rings? Seems to me that cog/ring material is not a very good indicator of overall robustness or longevity. These are wear items.
• This is NOT a Road bike thing. XTR cassettes used some ti cogs for a long time (not sure it they still do). And higher end MTB cranks come with Al rings instead of steel. This seem inconsistent with your claim that MTB components are expected to last longer (that is if you consider ring/cogs a measure of robustness).

I just don't get why folks don't see durability being an issue going from Claris to Tiagra to 105 to Ultegra (each step of which is lighter), but then suddenly it is with Dura Ace. It is all speculation and conjecture. It is not based on any experience or data.

Koyote

Sure, it was anecdotal. That's obvious, as it was presented as my experience. And I never claimed (nor implied) that 105 is "weak trash," so don't put words in my mouth. (In fact, after wearing out the 105 RD, I replaced it with another 105.)

I think you are probably correct, notwithstanding the few people in this thread who suggested that D/A might actually be less durable than Ultegra and 105.

Koyote

I scrolled back, and it looks like the OP was the first poster to raise this possibility of D/A being less durable, which (I agree) is nonsense. If you're looking for an excuse to NOT buy Dura Ace, find something else.

By the way, no one has mentioned why the D/A cassettes only use ti for the largest cogs - not for all of them. Sure, ti wears a bit faster...But the largest cogs naturally wear more slowly, mile per mile, because the chain wraps around more teeth and hence the stress is spread out. If anything, the larger ti cogs probably just 'catch up' and wear out at about the same time as the smaller cogs.

Kapusta

That is a very good point. 32t Ti cog does not need to last as long as a 32t steel cog. It only needs to last as long as as 18t steel cog it is sharing the cassettes with.

Maelochs

Yeah ... NO. YOU made that up.

What I said is that MTB components had to be Stronger at the higher end because they would be abused harder .... which is why they don't last as long as road components.

As for wear, check out the wear rates between Ti and steel. If you seriously think there is no difference in wear rates, fantastic.

Seriously .... if you want to pick a fight, at least pick on me for something I actually said. Have some honor.

Maelochs

And this has been stated above as well .... DA cassettes are expected to be replaced more frequently because they are aimed at racers who put a Lot of miles on their bikes. Cassettes are wear items, and in a race/training environment, will wear a lot faster than in a casual use situation.

Still, for most people paying a lot more for a DA cassette to save a few grams seems pound-foolish. The few dozen saved grams is generally considered money not well invested if there is no direct benefit (say, like getting a bike to UCI minimum (or below, for events sanctioned by other groups with lower weight limits.)

I'd like to direct your attention to this article from Velo News posted by Art's Cyclery .... argue with that guy. Shimano Road Components ? Where to Spend Your Money ? Art's SLO Cyclery

Sy Reene

Yeah, the point is straight off of the marketing copy from the likes of sellers such as competitive cyclist (below). Of course it all depends on which cogs get used the most for a given rider, the chainset, and/or the terrain they ride in.

Since Dura-Ace is the top-tier drivetrain in the Shimano road lineup, you might be surprised that only the largest five cogs are titanium. That's because—though it's lighter—titanium is generally more prone to wear than nickel-plated steel, and the smaller cogs are more prone to wear than the larger. Because of these material properties, Shimano only uses titanium where the softer metal doesn't create a significant negative impact.

Kapusta

Interesting insinuation: If the companies claim it, it must be false

Sorry, but in this case the claim totally makes sense.The point is that it is not just which cogs you use the most, it is that the even given equal use, the smaller ones wear out faster. And it explains why my Ti cassettes did not seem to wear out any faster. I for one have always noticed that it is always to cogs in the middle or upper end that ultimately wear out first, even though I use them less often.

pgjackson

If money is no object, of course you get the best thing available.

Will it make you go any faster? No
Will it impress your cycling friends? Probably

I look forward to reading more about your $15,000 Grand Fondo bike. I assume you are also getting a top of the line frame, wheels, cranks...

pdlamb

This.

Back when I was in school, I developed this philosophy (for lab electronics equipment back then, but it still holds in a number of areas). Latest and greatest only if it has something you desperately need that the next tier down doesn't have. But that shiny new model never has the field experience, troubleshooting, and fixes/upgrades the next step down has.

PeteHski

So are you suggesting that you can make something infinitely strong and light, if you just spend enough money on it? You would make a fortune in F1 if you knew how to do that because they seriously don't care what it costs to save a few grams!

All I'm saying is that for any given material and design you always have to compromise between weight and strength. That's just how it is in engineering. You can throw money at improving the strength/weight ratio e.g. carbon frames with exotic layups. But the compromise between strength/durability and weight still exists.
Likewise I don't know where the high end groups sit on that weight/durability spectrum. But I would imagine reducing weight was a top priority with top tier road groups because of their racing pedigree. XTR might actually be designed with durability as the major objective because of the different use case. Cheaper groups like 105 using more steel bits are likely to favour pretty well on durability at the expense of more weight.

My logic has nothing to do with cheapo engineered junk being weaker than lighter, much better engineered products using different design and materials. That's a poor analogy.

Kapusta

Who said anything about infinity strong and light? That is a strawman argument.

Your F1 engineering analogy is flawed here.

Yes, if you are comparing two no-expense-spared components, then the lighter one will likely be at the expense of strength. And here your F1 analogy would hold.

However, in the case of Ultegra vs DA, we are NOT comparing no-expense-spared components. Ultegra is NOT a no-expense-spared groupset. I'm not even sure that DA really is, but it certainly has a much larger budget to work with.

The reality is that the balance is NOT simply strength vs weight. It is strength vs weight vs cost. Your F1 analogy ignores last part of this as it is based on a scenario where cost is not a factor.

PeteHski

That probably about sums it up. I'm inclined to think durability is a none-issue with all these group sets.

Badger6

Durability in what way? Impacts? Perhaps. But in actual use, because of the way the technical aspects of the function trickle down in succeeding years, I'd wager that to get to a 105 that is more reliable in terms of operation (perhaps measured by using MTBF metrics?) than Dura-Ace, you'd need to compare current generation 105 to DA that is several generations old. In actual practice, I've almost exclusively used Ultegra and XT level components for years, and while not as light as their DA and XTR siblings, I've also never experienced failures over several hundred thousand kms that would make me think I should use 105 or SLX or Deore 6xxx.

PeteHski

You either get this or you don't. That's fine. Just because something is more expensive, it doesn't automatically follow that it will be stronger or more durable. Especially not if the main driver in the design of it was saving weight. DA as far as I know is not fundamentally a different design to Ultegra or 105. It just uses more expensive materials to save weight. That's slightly simplistic, but I think basically true.

Steel costs less than aluminium or Ti, but is actually stronger if you don't care about the weight. If you want to make a component durable, you make it out of steel.

Koyote

Kapusta

Steel costs less than aluminium or Ti, but is actually stronger if you don't care about the weight. If you want to make a component durable, you make it out of steel.

You either get this or you don't. That's fine. Just because something is lighter , it doesn't automatically follow that it will be weaker or less durable.

You are the one making the assumptions here, not me. You are assuming DA is weaker because it is lighter. But there are plenty of examples of bicycle components that provide counter examples of this assumption.

I am surprised to have to point this out to an engineer, but a component is as durable as the least durable part of that component. If a given part of that component is not the weak link than you can use a less durable material with no practical effect on the durability of the component.

I think the problem here is that you are speculating with theory, while I am talking about the actual components in question.

PeteHski

If you made a full DA set out of steel it would be more durable right? That's all I'm saying. The more you get into weight saving for a given design, the more fragile it then becomes. I'm not suggesting DA is fragile, but I'm certainly not going to presume it is more durable than Ultegra or 105, which both use more steel components. When you get further down the food-chain and plastic bits start getting used in place of steel and alloys, then the balance turns back the other way. Like the lowest tier Sram Eagle plastic-fantastic for example.

PeteHski

No I'm not assuming that. I'm just countering those who are presuming DA must be stronger/more durable because of the price.