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Shimano Ultegra Di2 6800 rim brakes obsolescence?

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Shimano Ultegra Di2 6800 rim brakes obsolescence?

Old 08-26-22, 11:51 AM
  #26  
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Originally Posted by Dave Mayer
Wow.... so many people bent out of shape when being faced with the cold reality that the bike industry went to road discs for commercial reasons.. Discs involve a significant cost (profit) upgrade, and also bind even somewhat competent riders to their shop for maintenance. Most riders can change a set of rim brake pads, but bleeding hydraulics? Nope. So its all good: the manufacturers and retailers win, plus it causes a wholesale changeout of the bike fleet, which is needed every few years to spawn new buzz and sales. Adding one more cog to the cassette every 7 years just wasn't enough to cause whole generations of bikes to become 'obsolete', but discs would serve to wipe out everything that came before. Win!


Keep in mind that most new road riders come from a MTB background, so they expect expensive, heavy and irrelevant features on road bikes, such as fat tires, suspension, dropper posts and discs. First rule of marketing: do not try and change your buyers first desires and perceptions - sell them what they want. Or think they want, even if it is misguided.


Bike builds: I build up several high-end bikes per year, based on rim-brake frames and wheels. Great times right now, especially due to cast-offs from sponsored teams and Walter Mitty riders. Yes, you can procure and then revive a UCI (team) level bike for $1k. High-end 10-speed wheels sell for nothing. Best value: 10-speed gear such as the amazing SRAM Red and Campy Chorus and Record gruppos. Or Dura-Ace 7800, the best of all the Shimano systems for shifting, or before Shimano inexplicably stuck the shifter cables under the bar wrap.


So 16-pound road bike for $1k. At that weight, a new bike with discs will cost you 5 x that much.
Lol. What a load of unmitigated poppycock.
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Old 08-26-22, 11:55 AM
  #27  
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Originally Posted by Dave Mayer
Bike builds: I build up several high-end bikes per year, based on rim-brake frames and wheels. Great times right now, especially due to cast-offs from sponsored teams and Walter Mitty riders. Yes, you can procure and then revive a UCI (team) level bike for $1k. High-end 10-speed wheels sell for nothing. Best value: 10-speed gear such as the amazing SRAM Red and Campy Chorus and Record gruppos. Or Dura-Ace 7800, the best of all the Shimano systems for shifting, or before Shimano inexplicably stuck the shifter cables under the bar wrap.

So 16-pound road bike for $1k. At that weight, a new bike with discs will cost you 5 x that much.
OK, so you can't confirm what $500 Asian sourced, new 800 gram frameset you were referring to. Instead, now you're using old team bikes, so again please provide examples of where these $500 bikes that you are using as the base for your builds are available for purchase.

For components, you refer to Dura-Ace 7800, which there are some group sets that are well used available online as low as $500, with many being well above that for excellent condition parts. This is not something to be directly compared against a brand new bike with all new components.

Based on your final comments there, you simply like old stuff and aren't interested in progress. I'm sure 20 years ago there was an equivalent of you claiming that the new fangled integrated shifters and too many speeds, when a cheap old used 10 speed bike with downtube shifters was a much better bargain. There's nothing wrong with being perfectly happy sticking with the equipment that you're used to. However, to dismiss everything newer as simply marketing hype that has no benefit is pretty narrow minded and you back it up with general opinion and not any actual facts.
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Old 08-26-22, 11:58 AM
  #28  
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Originally Posted by Dave Mayer
Wow.... so many people bent out of shape when being faced with the cold reality that the bike industry went to road discs for commercial reasons.. Discs involve a significant cost (profit) upgrade, and also bind even somewhat competent riders to their shop for maintenance. Most riders can change a set of rim brake pads, but bleeding hydraulics? Nope. So its all good: the manufacturers and retailers win, plus it causes a wholesale changeout of the bike fleet, which is needed every few years to spawn new buzz and sales. Adding one more cog to the cassette every 7 years just wasn't enough to cause whole generations of bikes to become 'obsolete', but discs would serve to wipe out everything that came before. Win!



Keep in mind that most new road riders come from a MTB background, so they expect expensive, heavy and irrelevant features on road bikes, such as fat tires, suspension, dropper posts and discs. First rule of marketing: do not try and change your buyers first desires and perceptions - sell them what they want. Or think they want, even if it is misguided.



Bike builds: I build up several high-end bikes per year, based on rim-brake frames and wheels. Great times right now, especially due to cast-offs from sponsored teams and Walter Mitty riders. Yes, you can procure and then revive a UCI (team) level bike for $1k. High-end 10-speed wheels sell for nothing. Best value: 10-speed gear such as the amazing SRAM Red and Campy Chorus and Record gruppos. Or Dura-Ace 7800, the best of all the Shimano systems for shifting, or before Shimano inexplicably stuck the shifter cables under the bar wrap.



So 16-pound road bike for $1k. At that weight, a new bike with discs will cost you 5 x that much.

Looking at this from a weight perspective, and I would agree with you. I didn't understand why road bikes needed discs - after all, I can lock up my 2004 Bianchi's rear wheel easily with Ultegra 6500 calipers. What's the point in the bloat and expense? Well, I was looking for a new bike a few years back - my Bianchi was 15 years old, and I wanted to get a titanium bike because... well, I wanted a titanium frame. I settled on the Lynskey R270, and got the disc version - not because I wanted to spend more money, but because I saw where the industry was going and I figured I'd have an easier go at getting replacement parts further into the future.


First, the downsides: Yes, the discs are heavy. As delivered, my 2019 Titanium Lynskey was almost exactly the same weight as my 2004 steel Bianchi - both Ultegra equipped. And the discs make noise if the disc is even *slightly* out of true, or warmed, or looked at the wrong way. I wondered if I had made a mistake and should've gone with the rim brake version. It's even annoying to put in the trunk - the thru axles are much slower than quick release levers, and the alignment is never exactly what it was before you took the wheels off - resulting in rotor zing until you get the wheel perfectly back in again.


And then piece by piece, the benefits started to come out.

- The front tire on my Lynskey fills out to nearly 32mm. It's big. It's fat. And at ~80psi, is both more comfortable, and corners more confidently, than the 25mm on my other bikes. I'm less skittish on fast descents, and less beat up 30mi in. I tried putting the same tire on my 2016 Cannondale CAAD 8, with SRAM Force rim brakes. No can do - tire rubs the top of the caliper.

- I'm now running 45mm carbon rims on the Lynskey. The Lynskey was already slightly faster than the Bianchi, but the deep section wheels makes cruising feel practically effortless. Why do I say this is a benefit of disc? Well, I don't want to run a deep dish carbon rim with rim brakes - I've heard bad stories about descents and wet weather braking. I don't want to run a deep dish alloy rim, either - that'll just add mass where it's most likely to be felt on accelerations and hills. There are deep dish carbon rims with alloy brake tracks, but there you get nearly the weight of alloy and all the expense of carbon all rolled into one.

- Thru-axles are annoying, but they're much stiffer than quick releases - I have to adjust how I expect my rim brake bikes to respond out-of-the-saddle after riding disc for a while. I don't think I've ever seen a rim brake bike with thru-axles.


Are disc brakes perfect? No. They add in headaches where there weren't any. Do they allow for more flexible choices in tires and wheels? Yes. Do those choices in tires and wheels allow more people to go faster under more conditions? I would say definitely.
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Old 08-26-22, 12:33 PM
  #29  
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Originally Posted by aliasfox
First, the downsides: Yes, the discs are heavy. As delivered, my 2019 Titanium Lynskey was almost exactly the same weight as my 2004 steel Bianchi - both Ultegra equipped. And the discs make noise if the disc is even *slightly* out of true, or warmed, or looked at the wrong way. I wondered if I had made a mistake and should've gone with the rim brake version. It's even annoying to put in the trunk - the thru axles are much slower than quick release levers, and the alignment is never exactly what it was before you took the wheels off - resulting in rotor zing until you get the wheel perfectly back in again..
Disc brakes are only about 200g heavier. Not a big deal.

https://cyclingtips.com/2022/06/a-co...o-disc-brakes/

I have 7 bikes (2 are road bikes) all with disc brakes. I have zero disc brake noise on any of the bikes and I've spent plenty of time looking at my disc brakes the wrong way.

Thru axles are slower than QR levers. However...The alignment IS exactly what is was when taking off and putting on the wheel. QR levers and disc brakes have the alignment issues. Not thru axles.
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Old 08-26-22, 12:53 PM
  #30  
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Originally Posted by prj71
Disc brakes are only about 200g heavier. Not a big deal.

https://cyclingtips.com/2022/06/a-co...o-disc-brakes/

I have 7 bikes (2 are road bikes) all with disc brakes. I have zero disc brake noise on any of the bikes and I've spent plenty of time looking at my disc brakes the wrong way.

Thru axles are slower than QR levers. However...The alignment IS exactly what is was when taking off and putting on the wheel. QR levers and disc brakes have the alignment issues. Not thru axles.
My rotors always zing after a hard stop, and the new front rotor that I installed on my new wheels wasn't delivered completely true. I've been able to flex it into place, but it definitely zings for a while after heavy braking.
The alignment tolerances on thru-axles are much tighter than on QR - but there's definitely a bit of wiggle room there, and I often have to try re-seating my wheels into the dropouts to get it right.
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Old 08-26-22, 12:56 PM
  #31  
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You don't need discs to run fat tires such as 32mm+. My 'cross bikes with V-brakes can easily handle these tires. TRP 8.4 rim brakes offer outstanding modulation and stopping power, and are compatible with road brake levers.

Thru-axles - I forgot to mention what a fussy time-consuming PITA these are. With standard quick-release wheels, you flip the lever, and the wheel drops out, just like Tullio Campagnolo meant it to happen. That is, after you do a little grinding on the lawyer tabs, which the industry was forced to adopt due to ambulance-chasing lawyers, and the broad industry conclusion that the riding public is incompetent.

To be clear, thru-axles are not axles, they do not bear rider forces, nor do bearings rotate around them. They are strictly wheel retention devices, which actually generate LESS axial wheel retention force than a standard QR lever when properly applied. I have never experienced a situation when a QR-equipped wheel shifted due to inadequate clamping forces.

This is how the sorry bike industry got to thru-axles:
  1. 1930's: Tullio Campagnolo's great invention
  2. 1980's: somebody hurt themselves using a QR wheel. Legal mayhem follows. Obviously in the US.
  3. 1980's: Butt-covering: lawyer tabs or 'wheel retention' tabs installed on all bikes, first in the US, and then the rest of the world caves in.
  4. 1980's onwards: now riders no longer attach wheels by clamping the QR, but they spin the QR lever. This results in inadequate retention forces.
  5. 1990's: discs take over MTBs, and discs eject front wheels due to extra braking forces at the fork ends. If users clamped their QR properly, then this would not be an issue.
  6. 2010's onward: The bike industry gives up on the assumption that users can figure out a QR when applied to discs. So an utterly foolproof system is needed: the thru-axle. This allows users to spin the lever to attach the wheel (like they were doing inappropriately with the QR).
  7. Onward: this has now spawned a chaos of incompatibility in the industry. Plus wheel changes are glacial.
Summary: a litany of legal butt-covering and incompetence.
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Old 08-26-22, 01:15 PM
  #32  
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Originally Posted by Dave Mayer
You don't need discs to run fat tires such as 32mm+. My 'cross bikes with V-brakes can easily handle these tires. TRP 8.4 rim brakes offer outstanding modulation and stopping power, and are compatible with road brake levers.

Thru-axles - I forgot to mention what a fussy time-consuming PITA these are. With standard quick-release wheels, you flip the lever, and the wheel drops out, just like Tullio Campagnolo meant it to happen. That is, after you do a little grinding on the lawyer tabs, which the industry was forced to adopt due to ambulance-chasing lawyers, and the broad industry conclusion that the riding public is incompetent.

To be clear, thru-axles are not axles, they do not bear rider forces, nor do bearings rotate around them. They are strictly wheel retention devices, which actually generate LESS axial wheel retention force than a standard QR lever when properly applied. I have never experienced a situation when a QR-equipped wheel shifted due to inadequate clamping forces.
Road bikes can't accommodate V-brakes.

Thru-Axles are used for alignment. They had disc brake bikes with QRs, and they didn't work very well for the very reason prj71 and I were discussing. QRs are absolutely abysmal at making sure a wheel is perfectly centered. Thru-axles have significantly less room for error in this regard.
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Old 08-26-22, 05:10 PM
  #33  
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Seems to me that a lot of folks exaggerate situations (in their own minds and in BF discussions). There's usually a kernel of truth, but it gets overblown.


"Disc brake bikes must be heavier, to deal with the increased stresses." Maybe the brakes themselves are a few ounces heavier, but the wheels, frame, and fork do not have to be. The fork is the only part that gets stressed more. Make it out of carbon fiber and it can handle that stress while also having better aero qualities and actually being lighter. Oh, and rims take much less wear, and you can stop faster in wet conditions, and other factors that you failed to weigh in your overall evaluation.


"The bike industry only switched to disc brakes to rake in more profit." Actually, they are quite good at discovering what will continue to bring profits in the long term. If disc brakes truly have all the drawbacks that are often cited and none of the benefits, consumers in our (mostly) free market economy will catch on, and the industry will return to rim brakes. I don't foresee it happening.


"Bikes today are harder for the average owner to maintain, and are also more expensive." They are indeed more expensive... as is everything. The reasons for this should be discussed in a politics sub-forum (over in Foo?). The average Joe-box-of-donuts has never had the skill, tools, or desires to maintain a bicycle beyond the most basic lubrication and adjustment tasks. Dedicated amateurs have always been capable of most repairs, and that's still the case, even with the most high performance, high tech bikes.


My favorite is "A bike with [whatever was state of the art when the commenter got into cycling] has everything you need and nothing you don't. It was perfectly situated on the cost/benefits graph. All the developments that came out since then are a pointless waste." But the guy a generation before you said the same thing about his state of the art. And young people today see your bike as an obsolete clunker, and so on.
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Old 08-26-22, 05:25 PM
  #34  
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Originally Posted by Dave Mayer
Thru-axles - I forgot to mention what a fussy time-consuming PITA these are. With standard quick-release wheels, you flip the lever, and the wheel drops out, just like Tullio Campagnolo meant it to happen. That is, after you do a little grinding on the lawyer tabs, which the industry was forced to adopt due to ambulance-chasing lawyers, and the broad industry conclusion that the riding public is incompetent.
Fussy time-consuming pain? Really? Have you ever removed or installed a through-axle wheel? It is a beautiful and elegant invention, as was the quick release skewer before it. On most of my QR equipped bikes, I file down the lawyer lips, because I know how to use the QR correctly. I thought I was enjoying the pinnacle of wheel retention technology. Then we bought my wife a hybrid bike with wonderful hydraulic disc brakes and a through axle on the front. The first time I removed the wheel, I thought, "That's kind of weird." Then, on reinstalling it, I said to myself, "Brilliant! If only everything were this simple." Granted, it takes a few seconds longer--in my entire life I might give up a cumulative total of three minutes. But it lines up so easily, every time. You don't even have to think about it. In making it idiot proof, they've given benefits to us non-idiots as well.

Last edited by Broctoon; 08-26-22 at 05:28 PM.
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Old 08-27-22, 08:59 AM
  #35  
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I used to build bikes for fun. I quit because the price of parts inflated ridiculously.

When Shimano went to its global pricing scheme and groupsets gain a 50-100 percent cost bump ..... when i could no longer get brand-new Ultegra from the UK for $500 and 105 for $375 or whatever (now both trending at twice that for mechanical) .... then building bikes, even with $500 frames, became less efficient than buying bikes.

Wheels I don't build, so I have to buy wheels. You can get super-cheap Ali-Express wheels I guess .... and you can trust them too .... if you want. Basically, $1500 was about as little as i could pay for a sub 17-pound (with pedals) ready-to-roll bike ... with new parts. And that is using bargain-basement cockpit gear, which usually worked out okay .... no fancy names, but i am not laying down 1000+ watts so I am not breaking stems or bars.

I want to see the receipts and the parts lists for those "$1000 16-lb bikes." I mean it. Don't just make the claim---back the claim. Because if you are paying $500 for the frame, you are getting a groupset and wheels for $500 .... and either you are buying junk, buying used, or lying.

$200 for the wheels .... $200 for the group set .... $100 for the cockpit, cabling, barrel adjusters, headset, tires, tubes? yeah, i want to see the documentation. If i am wrong, I will say so .... but if you cannot post pics of the receipts .... well .....
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Old 08-27-22, 09:18 AM
  #36  
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Originally Posted by Maelochs
I used to build bikes for fun. I quit because the price of parts inflated ridiculously.

When Shimano went to its global pricing scheme and groupsets gain a 50-100 percent cost bump ..... when i could no longer get brand-new Ultegra from the UK for $500 and 105 for $375 or whatever (now both trending at twice that for mechanical) .... then building bikes, even with $500 frames, became less efficient than buying bikes.

Wheels I don't build, so I have to buy wheels. You can get super-cheap Ali-Express wheels I guess .... and you can trust them too .... if you want. Basically, $1500 was about as little as i could pay for a sub 17-pound (with pedals) ready-to-roll bike ... with new parts. And that is using bargain-basement cockpit gear, which usually worked out okay .... no fancy names, but i am not laying down 1000+ watts so I am not breaking stems or bars.

I want to see the receipts and the parts lists for those "$1000 16-lb bikes." I mean it. Don't just make the claim---back the claim. Because if you are paying $500 for the frame, you are getting a groupset and wheels for $500 .... and either you are buying junk, buying used, or lying.

$200 for the wheels .... $200 for the group set .... $100 for the cockpit, cabling, barrel adjusters, headset, tires, tubes? yeah, i want to see the documentation. If i am wrong, I will say so .... but if you cannot post pics of the receipts .... well .....
My reference point is the 18lbs Cannondale that I built up last year. NOS 2016 CAAD8 frame and fork for $500, SRAM Force drivetrain with a Praxis Zayante S crank, Campy Zonda wheels, entry level carbon cockpit. All done up, I think she was about $2600. On the luggage scale last night, she weighed in at 17.95lbs with Look X-Track SPDs, carbon bottle cages, and a silicone phone mount that I was too lazy to take off.

Just a little more than $1k, and nowhere near 16lbs. Where did I go wrong?
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Old 08-27-22, 09:23 AM
  #37  
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Originally Posted by Dave Mayer
You don't need discs to run fat tires such as 32mm+. My 'cross bikes with V-brakes can easily handle these tires. TRP 8.4 rim brakes offer outstanding modulation and stopping power, and are compatible with road brake levers.

Thru-axles - I forgot to mention what a fussy time-consuming PITA these are. With standard quick-release wheels, you flip the lever, and the wheel drops out, just like Tullio Campagnolo meant it to happen. That is, after you do a little grinding on the lawyer tabs, which the industry was forced to adopt due to ambulance-chasing lawyers, and the broad industry conclusion that the riding public is incompetent.

To be clear, thru-axles are not axles, they do not bear rider forces, nor do bearings rotate around them. They are strictly wheel retention devices, which actually generate LESS axial wheel retention force than a standard QR lever when properly applied. I have never experienced a situation when a QR-equipped wheel shifted due to inadequate clamping forces.

This is how the sorry bike industry got to thru-axles:
  1. 1930's: Tullio Campagnolo's great invention
  2. 1980's: somebody hurt themselves using a QR wheel. Legal mayhem follows. Obviously in the US.
  3. 1980's: Butt-covering: lawyer tabs or 'wheel retention' tabs installed on all bikes, first in the US, and then the rest of the world caves in.
  4. 1980's onwards: now riders no longer attach wheels by clamping the QR, but they spin the QR lever. This results in inadequate retention forces.
  5. 1990's: discs take over MTBs, and discs eject front wheels due to extra braking forces at the fork ends. If users clamped their QR properly, then this would not be an issue.
  6. 2010's onward: The bike industry gives up on the assumption that users can figure out a QR when applied to discs. So an utterly foolproof system is needed: the thru-axle. This allows users to spin the lever to attach the wheel (like they were doing inappropriately with the QR).
  7. Onward: this has now spawned a chaos of incompatibility in the industry. Plus wheel changes are glacial.
Summary: a litany of legal butt-covering and incompetence.
That may not be entirely true. Modern rear hubs, that in load placement resembles old school free wheel hubs, may indeed benefit from a thick wall through axle bolt to internally support the hub axle and prevent it from bending.
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Old 08-28-22, 11:39 AM
  #38  
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Originally Posted by Racing Dan
That may not be entirely true. Modern rear hubs, that in load placement resembles old school free wheel hubs, may indeed benefit from a thick wall through axle bolt to internally support the hub axle and prevent it from bending.
Let's hope this isn't the case, as it would be really bad engineering. Obviously, you design the (real) axle inside the hub to take all forces, and do not depend on some secondary backup reinforcement which is skinny and made out of aluminum. This would imply that if you have to change your thru-axle (due to inevitable loss at some trailhead), then the replacement thru-axle may or may not be properly designed and constructed and could result in hub failure.

To recap: the thru-axle is not an axle, but simply a wheel retention device. It generates less compressive retention forces than a old-school quick-release axle properly applied. With a slight amount of attention and skill, QR hubset will drop into a frame with vertical dropouts and a standard fork perfectly every time, with zero alignment issues.

The only reason thru-axles exist, and their associated slow and fussy wheel changes, is the insulting assumption that the riding public is too incompetent to use a simple mechanical device.
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Old 08-29-22, 05:06 PM
  #39  
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Originally Posted by Dave Mayer
Let's hope this isn't the case, as it would be really bad engineering. Obviously, you design the (real) axle inside the hub to take all forces, and do not depend on some secondary backup reinforcement which is skinny and made out of aluminum. This would imply that if you have to change your thru-axle (due to inevitable loss at some trailhead), then the replacement thru-axle may or may not be properly designed and constructed and could result in hub failure.

To recap: the thru-axle is not an axle, but simply a wheel retention device. It generates less compressive retention forces than a old-school quick-release axle properly applied. With a slight amount of attention and skill, QR hubset will drop into a frame with vertical dropouts and a standard fork perfectly every time, with zero alignment issues.

The only reason thru-axles exist, and their associated slow and fussy wheel changes, is the insulting assumption that the riding public is too incompetent to use a simple mechanical device.
You may think its all obvious, however you need to take a moment to actually look for yourself. Most TA rear hubs do have a thin wall aluminium axle and the right hand hub bearing buried way in the hub, often behind the spokes (!) In some sense its even worse than old school free wheel hubs. This configuration is what breaks mtb and tandem hub with some frequency. A TA bolt that fits, will support the hub axle and prevent/help it not bending. You can argue all day it isn't "supposed" to do that, but it does and you really don't know if this is an intended feature or not. - I believe its a terrible design and I can only speculate why the more obvious design, with the ratchet/pawls inside the cassette, was abandoned. Modern mtb and even road cassettes have oodles of space that isn't utilized and instead the ratchet is crammed inside the hub shell.
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