Cycling Equipment · Public discussion

Can't get rear canti brake to skid tire. Should it?

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Cycling Equipment
Published
27 June 2008
Last activity
29 June 2008
Original author
TomYoung
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  1. Hi all:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such an
    old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad. A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar. The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    Anything else to be done, or is this as good as it gets?

    TIA

    Tom Young

  2. "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    Anything else to be done, or is this as good as it gets?

    You should be able to pretty easily get the rear wheel to skid from brake
    application.

  3. Tom Young said:

    Still working on that bike for my daughter (it was a "freebie"
    that's cost me about $50 in parts and lots of hours of work) and
    thanks to the help I've received here everything seems to be working
    fine, except that I can't get the rear cantilever brake to skid the
    tire. I'm not sure if being able to skid the rear tire really means
    anything in terms of fast and safe stops, but it seems odd that I
    can't accomplish this with this bike.

    I can't imagine a brake that can't skid the rear wheel, because
    skidding the rear wheel takes little effort on any working brake. I
    assume that the straddle cable is out of adjustment or the straddle
    cable yoke is bottoming on the cable housing anchor.

    Take the wheel out and see if pulling the hand lever can make the
    brake pads close to a narrower gap than the width of the rim. Beside
    that test, it wouldn't hurt to pull the cable out of the housing and
    wipe its entire length in with motor oil before threading it in again
    and attaching the straddle cable yoke. Do the same with the front
    brake. I don't know in what condition the cables have.

    Quoted message said:

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    Don't worry about that, just get the brake pads to move continuously
    and smoothly to make contact with the rim brake surfaces.

    Quoted message said:

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such
    an old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system
    doesn't seem too bad. A very hard squeeze of the brake handle
    brings the end of the handle to within a 1/4" of the bar.

    That doesn't sound good. When the pads make contact with the rim,
    about 3/4 of the distance to the hand lever running out of stroke
    should be used. If the system is so spongy that the rest of the
    stroke is mostly used up, you have an improperly installed cable
    housing.

    Quoted message said:

    The only thing I haven't done at this point is clean the rim
    sidewalls, but the sidewalls aren't particularly glazed with old
    brake pad material.

    I don't believe the brake pads are making effective contact with the
    rim.

    Quoted message said:

    Anything else to be done, or is this as good as it gets?

    It gets a lot better when these brakes are working.

    Jobst Brandt

  4. TomYoung said:

    Hi all:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such an
    old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad. A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar. The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    What kind of levers are installed?

  5. TomYoung said:

    Hi all:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such an
    old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad. A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar. The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    Anything else to be done, or is this as good as it gets?

    TIA

    Tom Young

    Is the V of the transverse cable to acute? This give a nice sturdy lever
    feel, but all you are accomplishing is you're trying to pull the brakes
    off the posts. Slide the posts of the blocks as far out as they will go .
    Many bikes come with the stock transverse cable doohicky in too big a
    size. Reverting to the old fashioned cable and cablehanger gives you
    more options
    --
    /Marten

    info(apestaartje)m-gineering(punt)nl

  6. Dan O said:
    TomYoung said:

    Hi all:

    Quoted message said:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    Quoted message said:

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts.  The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    Quoted message said:

    So... I've put on new cables and new housings and new housing
    ferrules.  Housing ends properly prepared as laid out at Sheldon
    Brown's site.  New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim.  (Remarkably, the wheels were quite true for such an
    old bike.)  Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad.  A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar.  The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    What kind of levers are installed?

    They look to me to be standard flat bar levers of the era. The
    sticker on them reads "Shimano Short Reach" but it doesn't look like
    any of the lever stroke has been adjusted out as the adjusting screws
    are fully withdrawn and the levers snap shut tight against the lever
    body. Maybe some sort of V-brake lever is what I have with attendant
    mechanical advantage issues?

  7. On Jun 27, 12:41 pm, [email hidden] wrote:
    I

    Quoted message said:

    I assume that the straddle cable is out of adjustment or the straddle
    cable yoke is bottoming on the cable housing anchor.

    I don't think the link wire/main cable setup (button/fixed length wire/
    main cable through button) is grossly out of whack. Picture of pads
    and rim are here (http://tinyurl.com/6qpprf) and link wire setup here
    (http://tinyurl.com/64fy3v). I could bring the pads *slightly* closer
    to the rim but would run up against a wheel that isn't *that* straight
    as well as lose the "quick release" aspect of the link wire setup.
    With the brake handle pulled tight against the handlebar the distance
    from the top of the link wire button to the hanger is 2 - 3
    centimeters.

    Quoted message said:


    Take the wheel out and see if pulling the hand lever can make the
    brake pads close to a narrower gap than the width of the rim. Beside
    that test, it wouldn't hurt to pull the cable out of the housing and
    wipe its entire length in with motor oil before threading it in again
    and attaching the straddle cable yoke. Do the same with the front
    brake. I don't know in what condition the cables have.

    With the wheel out the pads pull to within 23 - 24 mm of each other,
    measured center of pad to center of pad. The rim itself looks to be
    right at 28mm. The new cables are a Jagwire product with a PVDF
    coating and advise against lubing. I've used these successfully on
    other bikes but may try a standard lubed cable.

    Quoted message said:
    Quoted message said:
    Quoted message said:

    A very hard squeeze of the brake handle
    brings the end of the handle to within a 1/4" of the bar.

    That doesn't sound good. When the pads make contact with the rim,
    about 3/4 of the distance to the hand lever running out of stroke
    should be used. If the system is so spongy that the rest of the
    stroke is mostly used up, you have an improperly installed cable
    housing.

    Hand lever stroke is just at 6cm. Good solid pad/rim contact is at
    3cm. The "hard squeeze" I mentioned was with me squeezing the lever
    just about as hard as I can.

    I'd bet you money and give you odds that the cable housing setup when
    I got the bike was just as it was when the bike was sold, and that's
    what I copied in my installation. In any case, the arrangement seems
    right: housing from lever to to front top tube cable stop, then bare
    cable along the top tube to the rear cable stop, then housing from
    rear cable stop to hanger via reverse "S" bend with the middle of the
    "S" secured to the seat tube with a small collar. At this point the
    only change I can think of is shortening the first length of housing,
    which is probably a little long.

    Tom Young

  8. M-gineering said:
    TomYoung said:

    Hi all:

    Quoted message said:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    Quoted message said:

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts.  The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    Quoted message said:

    So... I've put on new cables and new housings and new housing
    ferrules.  Housing ends properly prepared as laid out at Sheldon
    Brown's site.  New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim.  (Remarkably, the wheels were quite true for such an
    old bike.)  Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad.  A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar.  The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    Quoted message said:

    Anything else to be done, or is this as good as it gets?

    Quoted message said:

    TIA

    Quoted message said:

    Tom Young

    Is the V of the transverse cable to acute? This give a nice sturdy lever
    feel, but all you are accomplishing is you're trying to pull the brakes
    off the posts. Slide the posts of the blocks as far out as they will go .
    Many bikes come with the stock transverse cable doohicky in too big a
    size. Reverting to the old fashioned cable and cablehanger gives you
    more options

    The link wire setup on this bike, front and rear, is the old-fashioned
    button with a fixed-length wire and the main cable running through the
    button to the other brake arm. The link wire for both brakes is the
    shortest one available, 73mm.

    You're suggesting (if I'm reading you right) that I slide the pads as
    far "away" from the brake arms as I can, thereby moving the tops of
    the brake arms away from the bike, compensating for this by lowering
    the link wire/main wire junction? So that the angle of the "V"
    increases?

    Tom Young

  9. M-gineering said:
    TomYoung said:

    Hi all:

    Quoted message said:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    Quoted message said:

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts.  The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    Quoted message said:

    So... I've put on new cables and new housings and new housing
    ferrules.  Housing ends properly prepared as laid out at Sheldon
    Brown's site.  New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim.  (Remarkably, the wheels were quite true for such an
    old bike.)  Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad.  A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar.  The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    Quoted message said:

    Anything else to be done, or is this as good as it gets?

    Quoted message said:

    TIA

    Quoted message said:

    Tom Young

    Is the V of the transverse cable to acute? This give a nice sturdy lever
    feel, but all you are accomplishing is you're trying to pull the brakes
    off the posts. Slide the posts of the blocks as far out as they will go .
    Many bikes come with the stock transverse cable doohicky in too big a
    size. Reverting to the old fashioned cable and cablehanger gives you
    more options

    You may have hit the nail on the head here.

    One thing I didn't mention, because it just didn't seem relevant, was
    that the bike has front and rear reflectors mounted to the fork crown
    and rear brake bridge. I ended up bending both of them down to give
    me a little more room for the link wire button when the brake was
    released but I didn't think a lot about the issue because my reasoning
    was "that's how they sold the bikes and the brakes must have worked OK
    when they sold them." However, in looking more closely at the front
    and rear brakes (the fronts seem to work OK) was that the brake arms
    up front formed a wider angle, by a good margin, then the brake arms
    in the rear. The limiting factor for the narrow angle in the rear is
    that rear reflector.

    Tomorrow I'll try again, either bending that rear reflector a heck of
    a lot more or removing it all together and widen the angle of the
    brake arms.

    Tom Young

  10. TomYoung said:
    Dan O said:
    TomYoung said:

    Hi all:
    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.
    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. �The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.
    So... I've put on new cables and new housings and new housing
    ferrules. �Housing ends properly prepared as laid out at Sheldon
    Brown's site. �New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. �(Remarkably, the wheels were quite true for such an
    old bike.) �Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad. �A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar. �The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.


    What kind of levers are installed?

    They look to me to be standard flat bar levers of the era. The
    sticker on them reads "Shimano Short Reach" but it doesn't look like
    any of the lever stroke has been adjusted out as the adjusting screws
    are fully withdrawn and the levers snap shut tight against the lever
    body. Maybe some sort of V-brake lever is what I have with attendant
    mechanical advantage issues?

    could well be. but you'd notice that same problem with the front brake
    as well, and that's not an issue you've raised so far...

  11. TomYoung said:

    Hi all:

    Still working on that bike for my daughter (it was a "freebie" that's
    cost me about $50 in parts and lots of hours of work) and thanks to
    the help I've received here everything seems to be working fine,
    except that I can't get the rear cantilever brake to skid the tire.
    I'm not sure if being able to skid the rear tire really means anything
    in terms of fast and safe stops, but it seems odd that I can't
    accomplish this with this bike.

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such an
    old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system doesn't
    seem too bad. A very hard squeeze of the brake handle brings the end
    of the handle to within a 1/4" of the bar. The only thing I haven't
    done at this point is clean the rim sidewalls, but the sidewalls
    aren't particularly glazed with old brake pad material.

    Anything else to be done, or is this as good as it gets?

    TIA

    Tom Young

    from those pictures, it would appear that the toe is excessive* and the
    pad/rim angle is not close enough - just a little contact area means
    just a little braking friction, and this is especially noticeable under
    load. try re-setting the pads accordingly. and double check to make
    sure the cables slide easily in their housings. a little friction in a
    long cable run takes a lot out of the force transfer.

    * you don't really need toe unless the brakes are squealing. trying to
    achieve the "modulation" effect toe creates is something of a
    misinformed objective since natural pad wear ensures the pads are
    parallel with the rim anyway, so you may as well get used to operating
    the brakes properly in the first place.

  12. [email hidden] wrote:
    <snip uninformative waffle>

    Quoted message said:

    In any event, a rear wheel
    should skid easily with moderate hand force, so there is something
    amiss here.

    why did you bother jobst? the o.p. had figured that bit out on their own.

    but i guess we should be grateful you're not making stuff up this time.

  13. "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    A simple response of "Tom, you ignorant [censored]" would have been
    sufficient.

    The problem is that you aren't ignorant, just misinformed.

  14. "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    Tomorrow I'll try again, either bending that rear reflector a heck of
    a lot more or removing it all together and widen the angle of the
    brake arms.

    Try this - when the brakes engage the wheel rim you should have
    approximately 45 degrees on the cable connector.

  15. Tom Kunich said:

    "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    Tomorrow I'll try again, either bending that rear reflector a heck of
    a lot more or removing it all together and widen the angle of the
    brake arms.

    Try this - when the brakes engage the wheel rim you should have
    approximately 45 degrees on the cable connector.

    with the link cable he has, that is not a variable!!! unless you want a
    cantilever that's lop-sided.

    bottom line, either it's centered or it's not. the angle is secondary.
    and it looks like the one that originally came with the brakes so it's
    unlikely to be wrong.

  16. Tom Kunich said:

    "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    A simple response of "Tom, you ignorant [censored]" would have been
    sufficient.

    The problem is that you aren't ignorant, just misinformed.

    you're not ignorant.

  17. jim beam said:
    Tom Kunich said:

    "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:


    A simple response of "Tom, you ignorant [censored]" would have been
    sufficient.

    The problem is that you aren't ignorant, just misinformed.

    you're not ignorant.

    ignorance is curable.

  18. jim beam said:
    jim beam said:
    Tom Kunich said:

    "TomYoung" <[email hidden]> wrote in message
    news:[email hidden]...

    >
    > A simple response of "Tom, you ignorant [censored]" would have been
    > sufficient.

    The problem is that you aren't ignorant, just misinformed.

    you're not ignorant.

    ignorance is curable.

    and you, tom, are not.

  19. Quoted message said:
    Quoted message said:

    Still working on that bike for my daughter (it was a "freebie"
    that's cost me about $50 in parts and lots of hours of work) and
    thanks to the help I've received here everything seems to be working
    fine, except that I can't get the rear cantilever brake to skid the
    tire. I'm not sure if being able to skid the rear tire really means
    anything in terms of fast and safe stops, but it seems odd that I
    can't accomplish this with this bike.

    Quoted message said:

    Tom Young wrote:
    I can't imagine a brake that can't skid the rear wheel, because
    skidding the rear wheel takes little effort on any working brake. I
    assume that the straddle cable is out of adjustment or the straddle
    cable yoke is bottoming on the cable housing anchor.
    Take the wheel out and see if pulling the hand lever can make the
    brake pads close to a narrower gap than the width of the rim. Beside
    that test, it wouldn't hurt to pull the cable out of the housing and
    wipe its entire length in with motor oil before threading it in again
    and attaching the straddle cable yoke. Do the same with the front
    brake. I don't know in what condition the cables have.

    Quoted message said:
    Tom Young said:

    The bike is an older mountain bike (26" wheels) hung with Shimano
    Exage 300LX parts. The brakes themselves just read "Shimano" but I
    assume they're either Exage 300LX or similar.

    Quoted message said:

    Don't worry about that, just get the brake pads to move continuously
    and smoothly to make contact with the rim brake surfaces.

    Quoted message said:
    Tom Young said:

    So... I've put on new cables and new housings and new housing
    ferrules. Housing ends properly prepared as laid out at Sheldon
    Brown's site. New brake pads (Ritchey Logic red) and new tires.
    Brake pads properly toed in and positioned equally close to either
    side of the rim. (Remarkably, the wheels were quite true for such
    an old bike.) Because of the highly sloped top tube the rear brake
    housing makes a fairly long reverse "S" bend to get up from the top
    tube to the rear brake hanger, but friction through the system
    doesn't seem too bad. A very hard squeeze of the brake handle
    brings the end of the handle to within a 1/4" of the bar.

    Quoted message said:

    That doesn't sound good. When the pads make contact with the rim,
    about 3/4 of the distance to the hand lever running out of stroke
    should be used. If the system is so spongy that the rest of the
    stroke is mostly used up, you have an improperly installed cable
    housing.

    Quoted message said:
    Tom Young said:

    The only thing I haven't done at this point is clean the rim
    sidewalls, but the sidewalls aren't particularly glazed with old
    brake pad material.

    Quoted message said:

    I don't believe the brake pads are making effective contact with the
    rim.

    Quoted message said:
    Tom Young said:

    Anything else to be done, or is this as good as it gets?

    Quoted message said:

    It gets a lot better when these brakes are working.

    All good advice. Besides which a kinked brake wire, transverse cable set
    excessively +/- 90 degrees, steel rims, reach-adjust levers set close,
    old dried pads or oil contaminated pads or many other foibles or
    oversights could affect this.
    --
    Andrew Muzi
    <www.yellowjersey.org/>
    Open every day since 1 April, 1971
    ** Posted from http://www.teranews.com **

  20. TomYoung said:

    On Jun 27, 12:41 pm, [email hidden] wrote:
    I

    Quoted message said:

    I assume that the straddle cable is out of adjustment or the straddle
    cable yoke is bottoming on the cable housing anchor.

    I don't think the link wire/main cable setup (button/fixed length wire/
    main cable through button) is grossly out of whack. Picture of pads
    and rim are here (http://tinyurl.com/6qpprf) and link wire setup here
    (http://tinyurl.com/64fy3v). I could bring the pads *slightly* closer
    to the rim but would run up against a wheel that isn't *that* straight
    as well as lose the "quick release" aspect of the link wire setup.
    With the brake handle pulled tight against the handlebar the distance
    from the top of the link wire button to the hanger is 2 - 3
    centimeters.

    Quoted message said:

    Take the wheel out and see if pulling the hand lever can make the
    brake pads close to a narrower gap than the width of the rim. Beside
    that test, it wouldn't hurt to pull the cable out of the housing and
    wipe its entire length in with motor oil before threading it in again
    and attaching the straddle cable yoke. Do the same with the front
    brake. I don't know in what condition the cables have.

    With the wheel out the pads pull to within 23 - 24 mm of each other,
    measured center of pad to center of pad. The rim itself looks to be
    right at 28mm. The new cables are a Jagwire product with a PVDF
    coating and advise against lubing. I've used these successfully on
    other bikes but may try a standard lubed cable.

    Quoted message said:
    Quoted message said:

    A very hard squeeze of the brake handle
    brings the end of the handle to within a 1/4" of the bar.


    That doesn't sound good. When the pads make contact with the rim,
    about 3/4 of the distance to the hand lever running out of stroke
    should be used. If the system is so spongy that the rest of the
    stroke is mostly used up, you have an improperly installed cable
    housing.

    Hand lever stroke is just at 6cm. Good solid pad/rim contact is at
    3cm. The "hard squeeze" I mentioned was with me squeezing the lever
    just about as hard as I can.

    I'd bet you money and give you odds that the cable housing setup when
    I got the bike was just as it was when the bike was sold, and that's
    what I copied in my installation. In any case, the arrangement seems
    right: housing from lever to to front top tube cable stop, then bare
    cable along the top tube to the rear cable stop, then housing from
    rear cable stop to hanger via reverse "S" bend with the middle of the
    "S" secured to the seat tube with a small collar. At this point the
    only change I can think of is shortening the first length of housing,
    which is probably a little long.

    I don't see any serious issues with the setup and the pads are an
    excellent choice.

    Oil on rim?

    You mention rear only trouble. If you set up the front similarly with
    the same model lever and it works well, we're most likely searching for
    a cable issue of some type.
    --
    Andrew Muzi
    <www.yellowjersey.org/>
    Open every day since 1 April, 1971
    ** Posted from http://www.teranews.com **

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