SRAM Hydraulic Disk Brakes

Discuss light weight issues concerning road bikes & parts.
dereksmalls
Posts: 2028
Joined: Tue Aug 02, 2011 9:20 pm
Location: New Zealand

by dereksmalls

BeeBee30 wrote:Damn those levers are ugly :shock:


I don't think they're that bad to be honest. So how would you design them?

by Weenie


User avatar
bobbyOCR
Posts: 1838
Joined: Sun Sep 03, 2006 1:55 pm
Location: Western Australia

by bobbyOCR

deltree wrote:SRAM trying to go forwards with hydraulic brakes when they should be looking at electronic shifting. Sure it makes sense for CX. But hydraulic brakes on road bikes are bad news.


Why?

And Why?

I still prefer mechanical groupsets. I think SRAM are still on the ball.

I will agree to a large extent with your second statement. There is a very limited calling for hydraulic brakes on the road. Rim or disc. The only advantage I can think of is discs being used to advance rim design. Some improved profiles and weights may be possible, but this is offset by the disc brake, of course.

Long descents may also be a good area for hydraulics.

I think those hydro levers look heinous. I hope they improve them.
Cyclist turned music producer

Visiting South West Australia? Visit Crank n' Cycles!

User avatar
yourdaguy
Posts: 2206
Joined: Thu Mar 17, 2005 3:25 am
Location: Southern Indiana USA
Contact:

by yourdaguy

Can't see a better way to package a master cylinder in road levers unless you integrate them in the bars and that would be a bad idea. As far as hydraulic shifting goes, it seems like the weight penalty would not equal the benefits which I mainly see as less sensitivity to dirt and grime. The front shifting on a double would be easy to implement but the rear might end up being kind of complicated. Although it would be way easier for SRAM to implement since they are starting with a pull ratio that is constant across the rear der.
For certain parts stiffer is more important than lighter.

User avatar
BeeBee30
Posts: 1474
Joined: Sun Dec 21, 2003 8:32 pm
Location: WALES,UK
Contact:

by BeeBee30

dereksmalls wrote:
BeeBee30 wrote:Damn those levers are ugly :shock:


I don't think they're that bad to be honest. So how would you design them?


I'm not saying I could do any better but the fact remains they are ugly, surely they could have made them a tad more streamlined, also I'm wondering how they are gonna feel honking out of the saddle?
Ti or dye!

The Weenie formally known as CAADHEAD

thisisatest
Shop Owner
Posts: 1980
Joined: Sat Jun 13, 2009 4:02 am
Location: NoVA/DC

by thisisatest

Hydro shifting doesn't have to be heavier. Acros system is about 150g lighter than XTR, I think.
Levers do look ugly. Would look less ugly if there was some visual separation between the traditional part of the lever body and its growth. It could pass for a bad Photoshop job as it is.

johnsaysthisnow
Posts: 16
Joined: Fri Jul 06, 2012 9:41 pm

by johnsaysthisnow

if hydraulic brakes are sort of the answer to a question nobody was asking (for road anyway. for cx, I can see its usefulness), then hydraulic shifting is DEFINITELY the answer to a question nobody was asking. Other than it being new and shiny technology, is there any mechanical or performance benefit to hydraulic shifting over mechanical? Better modulation on your shifts? :roll:

Also, wasn't one of the main drawbacks for road disc the type of braking encountered? Aside from the other pros/cons of disc implementation on road bikes, isn't a major concern SPECIFICALLY long mountain descents, with respect to heat buildup/dissipation and brake failure?

User avatar
yourdaguy
Posts: 2206
Joined: Thu Mar 17, 2005 3:25 am
Location: Southern Indiana USA
Contact:

by yourdaguy

Rim brakes have a greater problem with heat buildup on long descents because they can blow the tire off the rim. This is especially true on tandems and that is why many road tandems have for years had a rear disc brake (usually a 203mm rotor) and the newest ones have 10 inch rotors.

I think the advantages of hydraulic shifting would be that they almost wouldn't care about dirt/grime, etc. You could go an entire season without maintenance issues. Also, shifts could be easier since there would not need to be a spring to work against because the master cylinder position would be reflected in the slave cylinder position and the mechanism would only have to hold the place. All the power up or down could be from your finger. This could make front shifting especially easy because current designs use strong spring tension. This also means that you would have to push in a shift from the big ring to the small ring while current designs you just trip a release and the strong spring that you pulled against to shift up now shifts down for you so the levers would be more like Campy where you have a push on both sides.
For certain parts stiffer is more important than lighter.

dereksmalls
Posts: 2028
Joined: Tue Aug 02, 2011 9:20 pm
Location: New Zealand

by dereksmalls

johnsaysthisnow wrote: Also, wasn't one of the main drawbacks for road disc the type of braking encountered? Aside from the other pros/cons of disc implementation on road bikes, isn't a major concern SPECIFICALLY long mountain descents, with respect to heat buildup/dissipation and brake failure?


Was the same thing said about disc brakes on MTBs?

johnsaysthisnow
Posts: 16
Joined: Fri Jul 06, 2012 9:41 pm

by johnsaysthisnow

yes/no. MTB braking (typically) is less sustained than road braking of something like a long technical descent.

And yeah, true, disc brakes are used for applications like tandems where heat buildup on the rim is more critical, but those have been mechanical discs. Hydraulic discs still introduce the same problem of heat management, just at a new position.

Re: hydraulic shifting - I mean, I guess those are pros to hydraulic shifting? Personally, those are just non-issues.

User avatar
yourdaguy
Posts: 2206
Joined: Thu Mar 17, 2005 3:25 am
Location: Southern Indiana USA
Contact:

by yourdaguy

My 2004 Santana tandem has had hydraulic disc from the factory and I think it has been an option from Santana since the 90's. Santana has a master cylinder that works on cable pull so I have Ultegra levers but the rear has a short cable to a master cylinder on the down tuber that is hydraulic the rest of the way back.

If you think MTB use brakes less then you need to go to a ski resort in the Summer and try 4000 feet of vertical with a 40 lb 7 inch travel bike and see how much heat you put in the brakes. Also, road bikes on long descents get a lot of cooling as the air moves past the disc at 30 MPH or so.
For certain parts stiffer is more important than lighter.

MichaelB
Posts: 448
Joined: Tue Apr 22, 2008 4:31 am

by MichaelB

To see the hyd shifting integrated as well would be interesting.

After recently having tried the new Red on a bike (test review for an Aussie forum), I'm impressed in how well it worked, so I'm even more keen to go full hyd discs on my roadie (currently running TRP Parabox).

So why isn't there more info out there ?

User avatar
prendrefeu
Posts: 8610
Joined: Wed Oct 31, 2007 10:32 pm
Location: Los Feliz, Los Angeles, California
Contact:

by prendrefeu

johnsaysthisnow wrote:then hydraulic shifting is DEFINITELY the answer to a question nobody was asking. Other than it being new and shiny technology, is there any mechanical or performance benefit to hydraulic shifting over mechanical? Better modulation on your shifts?


Read this on the ACROS system, then get back to us.
http://www.bicycling.com/mountainbikeco ... t-acros-ge

Nevermind the cost - ACROS is a small company and currently all of their components are CNC'd individually at their facilities in Germany. Should a company such as SRAM pick up hydraulic shifting, expect to see the costs go way, way, way down.
Exp001 || Other projects in the works.

austke
Posts: 204
Joined: Mon Jan 16, 2012 7:03 am
Location: Queensland Australia

by austke

Cant wait for hydraulic disc brakes. Almost all modes of transport run this brake set up, why? Because it is better overall, thats what believe.
Both MTB and roadies are capable of the same descents (grade and or distance).
I dont think the SRAM set up is ugly. Nor can I compare to much until other makers jump onboard.
2013 Giant TCR Advanced SL 0, 6.92kg
2013 Giant Defy Composite 2 M, 8.5kg - Wife's
Azzurro Torino 8.55g
Fuji 650 10.8kg
Miele Lupa Triple Tandem 38,89kg

User avatar
yourdaguy
Posts: 2206
Joined: Thu Mar 17, 2005 3:25 am
Location: Southern Indiana USA
Contact:

by yourdaguy

SRAM should buy ACROS! That is so much better and lighter than electric shifting and should be way more reliable. The main concern was busting a cable but I run hydraulic brakes at much higher pressure and they never brake so I would expect this system to work for 3 years without any maintenance. Then change the fluid and go for another 3 years.
For certain parts stiffer is more important than lighter.

Dustin
Posts: 87
Joined: Wed Dec 14, 2011 4:37 pm

by Dustin

gospastic wrote:Image

Whose bike is that? Wondering why Zipp logos on bar/ stem are taped over.

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post