Some manufacturers forcing pros onto disk brakes for the 2019 season

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mattr
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by mattr

Yes, and one caliper is in front of the steering axis at the crown and one slightly less in front at the axle. Net zero (give or take.)

It's one reason why disc calipers are behind the fork. To keep them close to the steering axis.

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TobinHatesYou
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by TobinHatesYou

mattr wrote:
Wed Jun 05, 2019 9:28 pm
Yes, and one caliper is in front of the steering axis at the crown and one slightly less in front at the axle. Net zero (give or take.)

It's one reason why disc calipers are behind the fork. To keep them close to the steering axis.
Eh, the main reason is because the braking force is braced against the fork leg. Imagine if the caliper were on the other side and the catastrophic failures that could result.

All other reasons, including aerodynamics, are secondary.

mattr
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by mattr

TobinHatesYou wrote:
Wed Jun 05, 2019 9:32 pm
Eh, the main reason is because the braking force is braced against the fork leg. Imagine if the caliper were on the other side and the catastrophic failures that could result.

All other reasons, including aerodynamics, are secondary.
MattR wrote:one reason
Oh, the two manufacturers that i'm aware of that run it on the front of the fork, have probably had less "catastrophic failures" than the manufacturers that put it on the back of the fork leg.

TobinHatesYou
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by TobinHatesYou

mattr wrote:
Wed Jun 05, 2019 9:58 pm

Oh, the two manufacturers that i'm aware of that run it on the front of the fork, have probably had less "catastrophic failures" than the manufacturers that put it on the back of the fork leg.

Which two manufacturers do this? I'm genuinely curious. The most I've seen is bolt through designs like BMC uses, the caliper is still behind the fork, but the front adapter is no longer necessary.
Last edited by TobinHatesYou on Wed Jun 05, 2019 10:04 pm, edited 1 time in total.

AnkitS
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by AnkitS

Since everyone ignored what I said. Chad Haga said that having disc brakes on his TT bike allowed him to take corners faster than others (namely VC). He even prefaced his comment with "not trying to sound like a disc brake commercial" I am not cynical enough to believe that he would blatantly lie like that. :|

linked previously in the thread as well. https://youtu.be/oNMZ7LRCWxk?t=132
I really do not see why discs are a bad thing for TT bikes. You never have to change brake cables, pro teams can use the same wheels between the TT bikes and the road bikes. There can be more aggressive integration because cable routing and cable bends are not an issue with hoses. One drawback I can see if the frontal area of the brake levers. Although marginal, the S-900 brakes are HUGE. The Shimano and TRP ones are a lot smaller but pro teams have to remain within sponsor limitations.

Not sure if anyone here has any experience with a lathe but my limited experience in 8th-grade woodshop has taught me that if your bit is positioned incorrectly the tool could easily be ripped out of your hands. Similarly with disc brakes, if the brake caliper was positioned on the opposite side of the fork I could see the entire caliper being ripped out of it's threads.

AnkitS
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by AnkitS

[deleted my math is probably wrong lol]

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Konsi
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by Konsi

pdlpsher1 wrote:
Wed Jun 05, 2019 8:57 pm
I was watching a video on aero bikes by Hambini. He's an aerodynamicist and is someone I would trust because he has nothing to gain or lose by expressing his honest opinions. He said the aero loss on disks is significant because a disk is a spinning object vs. a stationary object. He said the disks are akin to a spinning wheel and that the wheel generates loads of drag. He reckons the aero penalty is around 8-9 watts at 40kph versus a claimed loss of only 2 watts by the bicycle manufacturers. If you are interested in the video here's the link. You can fast forward it to the 3:30 mark. https://www.youtube.com/watch?v=IgxFRNJ_HGs
I cannot access the video right now, but does it take into consideration that the disc rims can be optimised aerodynamically without the brake tracks?

TobinHatesYou
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by TobinHatesYou

Those tires must have some grip to stop a bike from 35 to 0 instantly. I’ll have to look at it later, but instantly braking from 35mph to 0mph would certainly result in more than 11n-m.

AnkitS
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by AnkitS

He does not talk about the rim profile at all in his video. ENVE made a huge fuss about the 5.6 rim vs the 5.6 disc rim profile and how the lack of a braking surface greatly improved aerodynamics but they have since removed the article from their "Journal" tab.

AnkitS
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by AnkitS

TobinHatesYou wrote:Those tires must have some grip to stop a bike from 35 to 0 instantly. I’ll have to look at it later, but instantly braking from 35mph to 0mph would certainly result in more than 11n-m.
Deleted my math was definitely not right.

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Lewn777
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by Lewn777

Calnago wrote:
Wed Jun 05, 2019 3:31 pm
TobinHatesYou wrote:Neither side needs justification based on what pros ride. Hope this helps.
In order to justify sponsoring pro teams etc., the pros had better be riding (come hell or highwater) what the manufacturers are wanting to sell. That’s the sole reason manufacturers sponsor in the first place. The pro peloton is cyclings biggest marketing stage. The fact that there is so much resistance at the pro level (at least by those who still have a choice) is a big thorn in the side of the marketing departments. Fanboys of discs at the consumer level like to pretend it doesn’t matter what the pros ride, but watch them jump up and down with glee whenever someone actually does win with discs. Comical.
:lol: :lol: :lol:

:thumbup:

spdntrxi
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by spdntrxi

Lewn777 wrote:
Thu Jun 06, 2019 12:08 am
Calnago wrote:
Wed Jun 05, 2019 3:31 pm
TobinHatesYou wrote:Neither side needs justification based on what pros ride. Hope this helps.
In order to justify sponsoring pro teams etc., the pros had better be riding (come hell or highwater) what the manufacturers are wanting to sell. That’s the sole reason manufacturers sponsor in the first place. The pro peloton is cyclings biggest marketing stage. The fact that there is so much resistance at the pro level (at least by those who still have a choice) is a big thorn in the side of the marketing departments. Fanboys of discs at the consumer level like to pretend it doesn’t matter what the pros ride, but watch them jump up and down with glee whenever someone actually does win with discs. Comical.
:lol: :lol: :lol:

:thumbup:
yeah by the same token.... someone comes along and has to point out the top3 or 5 or whatever (at the giro) where on non-or semi aero bikes sans disc... so it's not just the disc fanbois... it's also the luddites :)
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Calnago
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by Calnago

Like I prefaced it with... that’s getting old too. I like being a “Luddite”.
But it does highlight the continued reluctance to move to discs by the pros.
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spdntrxi
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by spdntrxi

Calnago wrote:Like I prefaced it with... that’s getting old too. I like being a “Luddite”. Image
But it does highlight the continued reluctance to move to discs by the pros.
Pros have the most to gain or lose by equip changes so I cant blame them. I don’t throw my bottles out before the county line sprint sign... so yeah they are different . I’m a Luddite at heart but my fingers and the rest of my hands love electronic and hydro
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Calnago
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by Calnago

spdntrxi wrote:Pros have the most to gain or lose by equip changes so I cant blame them.
That’s exactly why if the tech offered any significant advantage they would have adopted it years ago.

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