Advertise on Bikeforums.net



User Tag List

Results 1 to 9 of 9
  1. #1
    Senior Member
    Join Date
    Aug 2008
    Posts
    2,055
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    A Specific Cantilever Brake Design

    Hello
    Im looking for my dream brake, but the current distributor catalogs don't seem to offer anything that fits. Maybe someone here has seen it?

    Medium profile cantilever brake -allows fender clearance w/o sacrificing power

    threaded brake pads -so you can use cartridge pads

    barrel adjusting straddle wire -allows compensation for pad wear w/o raising straddle wire height

    pivot mounted cable anchor -avoids sharp cable bending/fraying over time

    independently adjustable return springs

    Imagine all the features of the tektro cr720, but in a medium instead of wide profile, so it has better mechanical advantage
    has anyone seen such a brake?
    Thanks

  2. #2
    AEO
    AEO is offline
    Senior Member AEO's Avatar
    Join Date
    Jun 2007
    Location
    A Coffin Called Earth. or Toronto, ON
    My Bikes
    Bianchi, Miyata, Dahon, Rossin
    Posts
    12,245
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    any avid shorty, but use the tektro 1246A yoke, which is the same yoke that comes with the CR720.

    barrel adjusting straddle wire -allows compensation for pad wear w/o raising straddle wire height
    I've never seen such a device before. The yoke needs to remain in the same position, otherwise the arms won't return an equal distance, and that's why at least one side of the straddle cable has a fixed length.

    Imagine all the features of the tektro cr720, but in a medium instead of wide profile, so it has better mechanical advantage
    if I remember correctly, wide profile has more mechanical advantage compared to medium profile
    Last edited by AEO; 11-20-11 at 08:40 PM.
    Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
    http://sanfrancisco.ibtimes.com/arti...ger-photos.htm

  3. #3
    coprolite fietsbob's Avatar
    Join Date
    Jun 2010
    Location
    NW,Oregon Coast
    My Bikes
    7
    Posts
    942
    Mentioned
    31 Post(s)
    Tagged
    0 Thread(s)
    Paul's touring version. they use independently adjustable return springs.
    you preload the spring tension with an open end wrench,
    and tightening the fixing 6mm allen bolt sets it in place.

    Neo Retro is the wide profile version, touring has the arms angled upward.
    and gains a bit more leverage than the L shaped sibling.
    Last edited by fietsbob; 11-20-11 at 09:26 PM.

  4. #4
    Senior Member
    Join Date
    Aug 2008
    Posts
    2,055
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    re AEO
    you're probably thinking of shimano 'link wire' style straddles, where one side is a housing of fixed length and the brake cable runs down it to one arm. older style yoke carriers use a second wire for the straddle, and the brake line terminates at the carrier in the center, this means you can have a barrel adjuster on the horizontal straddle wire and let any changes in length freely slide between the left and right arms.

    having a variable length horizontal straddle wire is important for me because:
    consider as pads wear down the distance to rim increases, typially we compensate for this by adjusting the barrel adjuster on the brake lever (at handlebar), this decreases the distane but also moves the pivot point of the straddle wire higher, resulting is less mechanical advantage
    a better solution is the have a barrel adjuster on the transverse cable, this directly pulls the arms in closer, but the pivot point stays at the same height, thus the same leverage is preserved throughout pad life

    a number of expensive brakes use this mechanism... but most don't meet all the other requirements in my list or have some other flaw...

    re: fietsbob
    the Paul touring canti is close to what I want, except the cable anchor doesn't pivot
    i should also clarify that i don't like the type of springs it uses, i'm looking for the type with a hex bolt adjuster on the side as found in most common v-brakes



    The Avid Shorty Ultimate Cantileveris close to what i want, (AEO: note the barrel adjuster at the tip of one arm) however it's flaw is that it has a 'folding' gimmik where the arms can be folded to either a wide profile or medium profile brake, which I just don't trust, also it has the inconvenient frontside adjustment springs

    Thanks for suggestions so far

  5. #5
    Real Men Ride Ordinaries fuzz2050's Avatar
    Join Date
    Sep 2008
    Posts
    3,642
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I swear I've seen a straddle cable made with a built in adjustment barrel, but I'm having trouble finding it just now. I think it was an old Velo Orange product, maybe if you email them they can give you a lead on tracking it down.

    Having the barrel adjuster straddle cable as a separate component would ease your search a bit.

  6. #6
    Mad bike riding scientist cyccommute's Avatar
    Join Date
    Nov 2004
    Location
    Denver, CO
    My Bikes
    Some silver ones, a black one, a red one, an orange one and a couple of titanium ones
    Posts
    15,639
    Mentioned
    13 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by xenologer View Post
    re AEO
    you're probably thinking of shimano 'link wire' style straddles, where one side is a housing of fixed length and the brake cable runs down it to one arm. older style yoke carriers use a second wire for the straddle, and the brake line terminates at the carrier in the center, this means you can have a barrel adjuster on the horizontal straddle wire and let any changes in length freely slide between the left and right arms.

    having a variable length horizontal straddle wire is important for me because:
    consider as pads wear down the distance to rim increases, typially we compensate for this by adjusting the barrel adjuster on the brake lever (at handlebar), this decreases the distane but also moves the pivot point of the straddle wire higher, resulting is less mechanical advantage
    a better solution is the have a barrel adjuster on the transverse cable, this directly pulls the arms in closer, but the pivot point stays at the same height, thus the same leverage is preserved throughout pad life

    a number of expensive brakes use this mechanism... but most don't meet all the other requirements in my list or have some other flaw...

    re: fietsbob
    the Paul touring canti is close to what I want, except the cable anchor doesn't pivot
    i should also clarify that i don't like the type of springs it uses, i'm looking for the type with a hex bolt adjuster on the side as found in most common v-brakes



    The Avid Shorty Ultimate Cantileveris close to what i want, (AEO: note the barrel adjuster at the tip of one arm) however it's flaw is that it has a 'folding' gimmik where the arms can be folded to either a wide profile or medium profile brake, which I just don't trust, also it has the inconvenient frontside adjustment springs

    Thanks for suggestions so far
    Jagwire makes the adjusters like those on the Avid brakes. They could probably be made to work with just about any brake.

    That said, I think you are making too much out of the pivot point issue. The difference in mechanical advantage would be minimal given the small amount of adjustment that is being made. You could also adjust the anchor bolt on the cable to take up the slack developed in the system with pad wear so that the anchor point stays in the same place. The lack of a pivot on the anchor bolt isn't going to cause and excessive amount if wear on the cable either. All of the frayed cables I've seen on cantilever brakes (or any brake for that matter) is due to over tightening of the cable at the anchor point.

    As for the spring adjustment on brakes, I find the type of adjustment that Paul (and some others) use to be superior to those found on v-brakes. They have a greater range of adjustment and allow for a finer tuning of the springs.
    Stuart Black
    Solo Without Pie. The search for pie in the Midwest.
    Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
    Days of Wineless Roads. Bed and Breakfasting along the KATY
    Twisting Down the Alley. Misadventures in tornado alley.
    An Good Ol' Fashion Appalachian Butt Whoopin'.

  7. #7
    L-time Cat4 & proud of it
    Join Date
    May 2006
    Location
    NoVA for now
    My Bikes
    There's 4... 1 of ea
    Posts
    173
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Shimano CX series of brakes?

    M

  8. #8
    coprolite fietsbob's Avatar
    Join Date
    Jun 2010
    Location
    NW,Oregon Coast
    My Bikes
    7
    Posts
    942
    Mentioned
    31 Post(s)
    Tagged
    0 Thread(s)
    Avid Ultimate, if it is so by definition , ultimate, apex, top of the heap.?

    Or just go for Magura's HS33, the hydraulic rim brake.

    they fit on cantilever/V bosses.
    Last edited by fietsbob; 11-21-11 at 10:18 AM.

  9. #9
    Senior Member
    Join Date
    Aug 2008
    Posts
    2,055
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    New Update;

    Tektro has just created my impossible to find dream brake
    http://www.tektro.com/_english/01_pr...e&sort=1&fid=2

    Now the long wait for it to get through distribution....

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •