The Great Braking Debate Thread (Disc/Rim/Cantilever/Fixie/InsertNewTechHere)

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blutto
Posts: 229
Joined: Thu Jun 21, 2012 5:09 pm

by blutto

mgrl wrote:
Thu Nov 25, 2021 7:58 pm
blutto wrote:
Thu Nov 25, 2021 7:36 pm
Btw....looked up Arkell v Pressdram ( 1971 )......hahahahahaha.....too funny...

Cheers
Good place to leave it I think before we just go back and forth endlessly on the same stuff!
Great idea....kinda think this thread has been, given the subject matter, sorta successful, and would be a pity if it got bogged down on something peripheral....

Cheers and Kind Regards

by Weenie


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spdntrxi
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by spdntrxi

^. what's your point?

this bike makes little to no attempt at weight savings with the parts chosen, not to mention the paintjob which is beautiful. As someone who has a TM01R, I can knock off have 400g-500g off that very easily.
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Maddie
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by Maddie

The same bike in rim option would be 7.6kg, so what?

dialtone
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Joined: Sun Oct 31, 2021 1:31 am

by dialtone

One argument that was made to me by LBS and that other folks here have also made, that I think doesn't hold much water, is: disc is the future of bike brakes.

The reason why it doesn't hold much water is easy: perhaps it's the case, but there's is absolutely no guarantee that the currently adopted standards for bike brakes (140/160 rotors and their thickness, flat mounts, hubs widths, thru axles etc) are going to remain totally unchanged through the years and the frameset you buy today will be compatible with all future innovations with disc brakes. If any other development area for bikes is any indication, everything will be different in 5 years time.

spdntrxi
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by spdntrxi

future ? it's the current.
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Lewn777
Posts: 1266
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by Lewn777

dialtone wrote:
Sun Nov 28, 2021 4:58 am
One argument that was made to me by LBS and that other folks here have also made, that I think doesn't hold much water, is: disc is the future of bike brakes.

The reason why it doesn't hold much water is easy: perhaps it's the case, but there's is absolutely no guarantee that the currently adopted standards for bike brakes (140/160 rotors and their thickness, flat mounts, hubs widths, thru axles etc) are going to remain totally unchanged through the years and the frameset you buy today will be compatible with all future innovations with disc brakes. If any other development area for bikes is any indication, everything will be different in 5 years time.
^^^^^^
This.

The bike industry has decided on disk brakes as a way to 'improve' road bikes, because 2% stiffer than last year's model really wasn't cutting it. They needed something really obviously noticeable to even the untrained eye like that could be seen as innovative to drive new sales and hike the prices. A difference your gran would notice.

Disk brakes were the ideal choice, but alas they are heavy and make the bike less fun to ride and provide almost no improvement in stopping power except for the initial lever squeeze in the rain. Worse, they are just a tweaking of the brakes that came on MTBs and a host of other bikes. 160mm rotors were OK with this system and 180/185, and 200/205 were far better especially with four piston calipers. Whereas 140mm rotors the ideal size and weight for road bikes provides poor stopping power,. Do disk brakes even scale down enough to be used effectively for road bikes or is it just always going to be a compromise? Time will tell.

What road bikes need are 100-140mm multi-material true floating rotors with lightweight reliable calipers that don't stick or drag so maybe springs are needed in the caliper body to hold the pistons further into their cores when not actuated for example, I'm not a mechanical design engineer but I hope they have some improvements in development. Eventually by slow evolution and likely added expense for the higher-end consumer these problems can be solved, but it's likely there will need to be new standards, especially in terms of caliper mounting.

The worse thing is the middle to lower end disk brake bike models. There is a noticeable increase in weight and price. Also for cost these bikes will end up with stamped out single piece rotors with poorly faced caliper mounts. Braking will always likely be poor and unreliable, in my view a complete waste of effort vs just sticking with rim bakes and such a shame as we could have just gone to direct mount.

openwheelracing
Posts: 371
Joined: Thu Jan 28, 2021 6:41 am

by openwheelracing

Maddie wrote:
Sat Nov 27, 2021 6:12 pm
The same bike in rim option would be 7.6kg, so what?
LOL you drew that one up too?

openwheelracing
Posts: 371
Joined: Thu Jan 28, 2021 6:41 am

by openwheelracing

Exactly. Looking forward to seeing future iterations/refinements of disc brake.

Singular
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by Singular

openwheelracing wrote:
Sun Nov 28, 2021 10:15 am
Maddie wrote:
Sat Nov 27, 2021 6:12 pm
The same bike in rim option would be 7.6kg, so what?
LOL you drew that one up too?
What's your guesstimate, then?

spdntrxi
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by spdntrxi

openwheelracing wrote:
Sun Nov 28, 2021 10:24 am
Exactly. Looking forward to seeing future iterations/refinements of disc brake.
sagan's old venge vias rim brake bike with deep wheels was 7.6kg.. Aero bike with no weight weenieisms. Although I little bigger then TM01R you posted, not enough not make a difference. A 51 BMC is like a 53/54
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bobones
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by bobones

I have been thinking long and hard about whether to stick with rim or jump to disc for my new frameset, but I've decided to go with another rim brake bike.

Nothing in this thread or elsewhere really convinced me that disc was the better option for me at this time, even though I found a couple of amazing disc frameset deals and was really curious about trying discs in general.

These are the things that finally swayed it:

1/ I already have a couple of decent carbon rim brake wheelsets to use instead of having to buy or build new disc wheels,
2/ I really don't need the extra stopping power for my type of riding
3/ carbon brake tracks don't wear fast and this isn't a wet weather bike anyway
4/ the noise and/or accelerated pad wear of discs in wet conditions is still a concern when I do get caught in the rain
5/ For me, rim brakes are easier to deal with in general (no bedding in, no warped rotors, pad wear easily visible, on the road adjustments easier, less worry about contamination, no new tools to buy, etc.),
6/ External rim brake cables are a wee bit neater at the front end than external disc cables (not interested in full integration).
7/ This is a climbing bike so my eyes will be on the scales, and the rim version will be lighter in the final build.
8/ I think the rim brake version looks a bit more elegant and will possibly have better ride quality and aero characteristics
9/ I am not concerned about future resale value as I tend to keep bikes for a very long time
10/ When I questioned why I wanted a disc bike it was really curiosity, having new tech to play with and perhaps pressure from marketing pushing me to discs (rim brakes are dead, old tech from a bygone era, no one buys or wants rim bikes these days, discs look cooler, blah blah).
11/ Durianrider says discs are crap! :mrgreen:

I am not really looking for an argument here as it's all been said already: I am just relaying my thought processes.

So, after almost pulling the trigger on a custom painted ARC8 Escapee, what I have finally bought is a Factor O2 in Miami blue with the Black Inc kit, and will be using SRAM Red AXS and El Tornado EE brakes.

I already have an aero bike, so this wasn't a concern (I opted for 38 mm bars so I will probably save enough watts there from my usual 40s!).

I could've got the same model disc frameset for a few hundred pounds less or a O2 VAM disc for just a few hundred much more, so it was a quite a tough decision, but hopefully I've made the right one! :noidea:

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wheelsONfire
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by wheelsONfire

EE brakes with Schwalbe S-One 30mm tires
Moots road fork, sanded and painted with gloss clear coat, 293g with crown race.
3T Rigida Ltd, with same crown race cut to same length is 284g.
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Last edited by wheelsONfire on Tue Nov 30, 2021 3:41 pm, edited 1 time in total.
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

subparmotive
Posts: 14
Joined: Sun Nov 14, 2021 9:56 pm

by subparmotive

bobones wrote:
Mon Nov 29, 2021 6:50 pm
hopefully I've made the right one! :noidea:
Don't worry, you made the right choice. I'm currently stuck with a disc brake bike that I absolutely hate, cant wait to get back to the simple life with rim brakes.

tomato
Posts: 729
Joined: Mon Jul 01, 2019 8:37 pm

by tomato

bobones wrote:
Mon Nov 29, 2021 6:50 pm
These are the things that finally swayed it:

1/ I already have a couple of decent carbon rim brake wheelsets...
.
.
.
You were doing so well, building a case based on rational thinking, until ...
bobones wrote:11/ Durianrider says discs are crap!

by Weenie


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