Chainring wear on the track?

Discussion in 'Cycling Equipment' started by Pete Biggs, Apr 14, 2003.

Thread Status:
Not open for further replies.
  1. Pete Biggs

    Pete Biggs Guest

    I've just bought a used TA 50t chainring via eBay (for more than peanuts). It was described as
    "brand new (used once on for a pursuit on the track)".

    Nevermind the obvious contradiction between brand new and used, but how much wear could result from
    one track pursuit?

    The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road to
    me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know what
    both new and well used ones look like.

    I've got no personal experience with track riding. Are the extra stresses on the track so much
    greater that a chainring can be this worn after just one race?

    Thanks for any help. I'm considering asking for a discount or refund. EBay's feedback is a handy
    facility, isn't it :)

    ~PB (no digital camera or scanner so can't post a picture easily)
     
    Tags:


  2. Anonymous

    Anonymous Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...

    > The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    > "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road
    > to me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know
    > what both new and well used ones look like.

    Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I bought
    recently have had).

    clive
     
  3. Pete Biggs

    Pete Biggs Guest

    Clive George wrote:

    >> The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    >> "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road
    >> to me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know
    >> what both new and well used ones look like.
    >
    > Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I bought
    > recently have had).

    No.

    ~PB
     
  4. Anonymous

    Anonymous Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > Clive George wrote:
    >
    > >> The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    > >> "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the
    > >> road to me - with ordinary road bike & cycling, and I do have specific experience of TA rings
    > >> so know what both new and well used ones look like.
    > >
    > > Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I
    > > bought recently have had).
    >
    > No.

    Ok, I'll rephrase it then.

    The last couple of 36t 110mm TA chainrings I have bought have had little steps on one side of the
    valley. (these were new chainrings). I've just checked, and they're still there now.

    clive
     
  5. Pete Biggs

    Pete Biggs Guest

    Clive George wrote:

    >>> Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I
    >>> bought recently have had).
    >>
    >> No.
    >
    > Ok, I'll rephrase it then.
    >
    > The last couple of 36t 110mm TA chainrings I have bought have had little steps on one side of the
    > valley. (these were new chainrings).

    New when? I'm wondering how many miles you've done on yours already.

    > I've just checked, and they're still there now.

    I'm not sure what you mean but I doubt it's relevant. The tips of the teeth are profiled and the
    chainrings do have several "half" teeth (to aid shfting) but this is not what I'm talking about.
    Thanks anyway.

    New TA chainring teeth are symmetrical when viewed from the side and feel smooth between the teeth
    when tested with a fingernail. I'm sure of this because I've checked a brand new new TA ring I
    fitted last Thursday, and even two others that I've been using for a few months show little sign of
    wear at all. The used one in question has slightly shark-like teeth with ridges on the bottom edges
    (where the chain rollers contact). It's all definitely caused by wear. My only doubt is about how
    much useage on a track bike would cause this. (I know those guys really hammer their machinery :)

    I've owned 5 TA chainrings of various sizes over the last 4 years and they're all basically of
    the same design. I've done several thousand miles on a couple of them (some of that with a
    worn-out chain) and even these don't look "twice as worn" as this "new" second-hand one, if you
    know what I mean.

    ~PB
     
  6. Mark

    Mark Guest

    "Pete Biggs" wrote
    > I've just bought a used TA 50t chainring via eBay (for more than peanuts). It was described as
    > "brand new (used once on for a pursuit on the track)".
    >
    > Nevermind the obvious contradiction between brand new and used, but how much wear could result
    > from one track pursuit?
    >
    > The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    > "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road
    > to me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know
    > what both new and well used ones look like.
    >
    > I've got no personal experience with track riding. Are the extra stresses on the track so much
    > greater that a chainring can be this worn after just one race?
    >
    > Thanks for any help. I'm considering asking for a discount or refund. EBay's feedback is a handy
    > facility, isn't it :)
    >
    > ~PB (no digital camera or scanner so can't post a picture easily)
    >
    On the occasions that I've sold items on e-bay, prospective buyers have asked me to e-mail them
    close up pictures of specific parts of the item for sale, or pictures taken from a particular
    perspective. This is not a difficult task for someone with a digital camera, even a cheap POS
    camera like mine. Perhaps you could have asked for a close up picture of the chainring teeth before
    placing a bid?
    --
    mark
     
  7. Pete Biggs

    Pete Biggs Guest

    mark wrote:
    > On the occasions that I've sold items on e-bay, prospective buyers have asked me to e-mail them
    > close up pictures of specific parts of the item for sale, or pictures taken from a particular
    > perspective. This is not a difficult task for someone with a digital camera, even a cheap POS
    > camera like mine. Perhaps you could have asked for a close up picture of the chainring teeth
    > before placing a bid?

    How does that help me now? Yes it is a good idea but the seller didn't have any pictures at all.
    I've certainly learnt my lesson, but would still appreciate any technical replies to help me decide
    on how much refund to claim if any. Any track riders in the house?

    ~PB
     
  8. Anonymous

    Anonymous Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > Clive George wrote:
    >
    > >>> Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I
    > >>> bought recently have had).
    > >>
    > >> No.
    > >
    > > Ok, I'll rephrase it then.
    > >
    > > The last couple of 36t 110mm TA chainrings I have bought have had little steps on one side of
    > > the valley. (these were new chainrings).
    >
    > New when? I'm wondering how many miles you've done on yours already.

    Last Oct, and sometime before that. 2000 mi or so on this one. I remember being a bit surprised at
    this tooth profile, but haven't met any problems with it. Now these could have a different profile
    to the ones you get, as mine are 110mm = MTB, and they are advertised as being different to avoid
    chain suck.

    > > I've just checked, and they're still there now.
    >
    > I'm not sure what you mean but I doubt it's relevant. The tips of the teeth are profiled and the
    > chainrings do have several "half" teeth (to aid shfting) but this is not what I'm talking about.
    > Thanks anyway.

    It isn't what I'm talking about either...

    > New TA chainring teeth are symmetrical when viewed from the side and feel smooth between the teeth
    > when tested with a fingernail. I'm sure of this because I've checked a brand new new TA ring I
    > fitted last Thursday, and even two others that I've been using for a few months show little sign
    > of wear at all. The used one in question has slightly shark-like teeth with ridges on the bottom
    > edges (where the chain rollers contact). It's all definitely caused by wear. My only doubt is
    > about how much useage on a track bike would cause this. (I know those guys really hammer their
    > machinery :)

    and they use 1/8" rather than 3/32" normally

    > I've owned 5 TA chainrings of various sizes over the last 4 years and they're all basically of
    > the same design. I've done several thousand miles on a couple of them (some of that with a
    > worn-out chain) and even these don't look "twice as worn" as this "new" second-hand one, if you
    > know what I mean.

    If the tooth is even slightly flared where the chain roller touches it, that's unacceptable wear
    imo. (far too much experience of chainsuck attributable to such things).

    Certainly the original advert implied very little wear ("brand new"), so I'd probably say send it
    back/get a refund.

    cheers, clive
     
  9. John Dacey

    John Dacey Guest

    On Mon, 14 Apr 2003 12:38:15 +0100, "Clive George"

    >"Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    >news:[email protected]...
    >
    >> The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    >> "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road
    >> to me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know
    >> what both new and well used ones look like.
    >
    >Don't new TA rings have a little step in the bottom of the valley? (fairly sure the ones I bought
    >recently have had).
    >

    A few years ago, TA. introduced a chainring tooth profile they called "Contact". Quoting from one of
    their brochures:

    "TA has produced an asymmetric tooth construction 'Contact'. It is the first of its type and shortly
    will be patented. 'Contact' ensures the longer life of your chainring because it exerts the most
    amount of force directly on the chain roller on the pulling side of the chainring tooth. The scooped
    machining of the bottom of the tooth eliminates the effect of mud and water when the components make
    'Contact' even in the very worst conditions, premature wearing of componentry is reduced. Chain to
    ring mesh is totally unaffected by the new TA concept which in its entirety now offers what is
    probably the best chainring gear changes".

    When the 'Contact' profile appeared, I promptly stopped listing TA's
    1/8" chainrings for 144 bolt pattern cranks in our track catalog. Insofar as I know, 'Contact'
    'rings work competently (even if they don't have the magic qualities claimed in the brochure), but
    I couldn't see having to try to explain this over and again to customers when I had high quality
    ungimmicked track chainrings from another mfr at a similar price point to offer.

    - - - - - - - - - - - - - - - http://www.businesscycles.com John Dacey Business Cycles Miami,
    Florida 305-273-4440
    - - - - - - - - - - - - - - - Now in our twentieth year. Our catalogue of track equipment: seventh
    year online
     
  10. Pete Biggs

    Pete Biggs Guest

    Clive George wrote: /snip
    >> It's all definitely caused by wear. My only doubt is about how much useage on a track bike would
    >> cause this. (I know those guys really hammer their machinery :)
    >
    > and they use 1/8" rather than 3/32" normally

    That's the internal width rather than pitch*, I believe. Could that make any difference to wear?

    * www.sheldonbrown.com/gloss_p.html

    > If the tooth is even slightly flared where the chain roller touches it, that's unacceptable wear
    > imo. (far too much experience of chainsuck attributable to such things).

    Thanks Clive. That gives me more confidence.

    ~PB
     
  11. Anonymous

    Anonymous Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > Clive George wrote: /snip
    > >> It's all definitely caused by wear. My only doubt is about how much useage on a track bike
    > >> would cause this. (I know those guys really hammer their machinery :)
    > >
    > > and they use 1/8" rather than 3/32" normally
    >
    > That's the internal width rather than pitch*, I believe. Could that make any difference to wear?

    yup. Obviously the fatter ring will have more resistance to eg flaring, as there's more area for the
    chain to push on.

    The relevance is that if the seller was using a 3/32" ring where people normally use 1/8", it could
    wear quite a lot faster than normal.

    (if it were pitch, you'd end up with a very silly chain! But imagine the gearing increments you
    could have..)

    cheers, clive
     
  12. Ronald

    Ronald Guest

    > Any track riders in the house?

    Maybe also try this one in rec.bicycles.racing, you'll propably find more trackies there.

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > mark wrote:
    > > On the occasions that I've sold items on e-bay, prospective buyers have asked me to e-mail them
    > > close up pictures of specific parts of the item for sale, or pictures taken from a particular
    > > perspective. This is not a difficult task for someone with a digital camera, even a cheap POS
    > > camera like mine. Perhaps you could have asked for a close up picture of the chainring teeth
    > > before placing a bid?
    >
    > How does that help me now? Yes it is a good idea but the seller didn't have any pictures at all.
    > I've certainly learnt my lesson, but would still appreciate any technical replies to help me
    > decide on how much refund to claim if any. Any track riders in the house?
    >
    > ~PB
     
  13. Pete Biggs

    Pete Biggs Guest

    Ronald wrote:

    >> Any track riders in the house?
    >
    > Maybe also try this one in rec.bicycles.racing, you'll propably find more trackies there.

    I can't get any messages to download from that group. Is it still going ok? I tried "resetting" my
    local file.

    cheers ~PB
     
  14. Mike S.

    Mike S. Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > Ronald wrote:
    >
    > >> Any track riders in the house?
    > >
    > > Maybe also try this one in rec.bicycles.racing, you'll propably find more trackies there.
    >
    > I can't get any messages to download from that group. Is it still going ok? I tried "resetting" my
    > local file.
    >
    > cheers ~PB

    Unless you like being insulted, don't bother with rbr. Lots of flame wars over there. Not many
    trackies there anyway.

    Mike
     
  15. Pete Biggs

    Pete Biggs Guest

    John Dacey wrote:
    > A few years ago, TA. introduced a chainring tooth profile they called "Contact". Quoting from one
    > of their brochures:
    >
    > "TA has produced an asymmetric tooth construction 'Contact'. It is the first of its type and
    > shortly will be patented. 'Contact' ensures the longer life of your chainring because it exerts
    > the most amount of force directly on the chain roller on the pulling side of the chainring tooth.
    > The scooped machining of the bottom of the tooth eliminates the effect of mud and water when the
    > components make 'Contact' even in the very worst conditions, premature wearing of componentry is
    > reduced. Chain to ring mesh is totally unaffected by the new TA concept which in its entirety now
    > offers what is probably the best chainring gear changes".

    John, Thank you very much. I'm very embarrassed!! This ring is probably is indeed one of the
    "Contact Profile" models. I've just dug out a card that came with one of my previous TA rings (40t)
    and the diagrams show teeth that do look like the ones of the new ring I have, even complete with
    the little ridges.

    It's weird and confusing because:
    a) I can't recall noticing these details before
    b) The profile really does look similar to what you see on worn-out rings!
    c) The other TA ring I just bought (new elsewhere) is definitely not Contact Profile and has
    regular teeth.

    I still think it's likely that it's been used at least a little bit more than described though -
    especially because of the scratching on the front, but I'm now prepared to give the seller the
    benefit of the doubt and I'll keep the ring.

    cheers ~PB [message x-posted to r.b.t, r.b.m and uk.rec.cycling]
     
  16. John Dacey

    John Dacey Guest

    On Mon, 14 Apr 2003 18:58:48 +0100, "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote:

    >John Dacey wrote:
    >> A few years ago, TA. introduced a chainring tooth profile they called "Contact". Quoting from one
    >> of their brochures:
    >>
    >> "TA has produced an asymmetric tooth construction 'Contact'. It is the
    <snipped>
    >> the best chainring gear changes".
    >
    >John, Thank you very much. I'm very embarrassed!! This ring is probably is indeed one of the
    >"Contact Profile" models. I've just dug out a card that came with one of my previous TA rings (40t)
    >and the diagrams show teeth that do look like the ones of the new ring I have, even complete with
    >the little ridges.

    You're not the only one to be caught out on this. The arrival of "Contact" came without fanfare,
    or even acknowledgement of the change on TA's packaging. When they first came out, I took back a
    few I had sold as "defective" and didn't become aware of it until I contacted the supplier I'd
    gotten them from to return them for credit. It was only then did I discover that "it's not a flaw,
    it's a feature".

    >It's weird and confusing because:
    > a) I can't recall noticing these details before
    > b) The profile really does look similar to what you see on worn-out rings!
    > c) The other TA ring I just bought (new elsewhere) is definitely not Contact Profile and has
    > regular teeth.

    I also have some TA track (1/8") chainrings they do for cranks with 130 bolt patterns in stock that
    have normal teeth. Go figure.
    - - - - - - - - - - - - - - - http://www.businesscycles.com John Dacey Business Cycles Miami,
    Florida 305-273-4440
    - - - - - - - - - - - - - - - Now in our twentieth year. Our catalogue of track equipment: seventh
    year online
     
  17. A Muzi

    A Muzi Guest

    "Pete Biggs" <pLime{remove_fruit}@biggs.tc> wrote in message
    news:[email protected]...
    > I've just bought a used TA 50t chainring via eBay (for more than peanuts). It was described as
    > "brand new (used once on for a pursuit on the track)".
    >
    > Nevermind the obvious contradiction between brand new and used, but how much wear could result
    > from one track pursuit?
    >
    > The teeth on this ring are noticeably hooked and have distinct ridges on the bottom of the
    > "valleys". The wear seems the equivalent of several hundred miles (at the very least) on the road
    > to me - with ordinary road bike & cycling, and I do have specific experience of TA rings so know
    > what both new and well used ones look like.
    >
    > I've got no personal experience with track riding. Are the extra stresses on the track so much
    > greater that a chainring can be this worn after just one race?
    >
    > Thanks for any help. I'm considering asking for a discount or refund. EBay's feedback is a handy
    > facility, isn't it :)

    I have seen a Campagnolo chainring completely ruined in less than fifty miles of riding after being
    run with an overtightened fixed chain. So it is possible to be both "nearly new" and "dead".

    Whatever happened IMHO you were sold a chainring with no useful life remaining and he should refund
    your paymnet if all is as you describe.

    --
    Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
     
  18. Pete Biggs

    Pete Biggs Guest

    A Muzi wrote:
    > I have seen a Campagnolo chainring completely ruined in less than fifty miles of riding after
    > being run with an overtightened fixed chain. So it is possible to be both "nearly new" and "dead".
    >
    > Whatever happened IMHO you were sold a chainring with no useful life remaining and he should
    > refund your paymnet if all is as you describe.

    As I explained in previous replies, I was mistaken and this TA ring is a "Contact Profile" model
    with asymetric teeth.

    In any case, "no useful life" would have been an exaggeration. It sort of looks like a regular ring
    when it's _partly_ worn, not completely worn out.

    ~PB
     
Loading...
Thread Status:
Not open for further replies.
Loading...