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A problem with gears.

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UK and Europe
Published
8 December 2004
Last activity
22 December 2004
Original author
Donny
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  1. Hi there,

    I'm new to this forum, so hello everyone!

    I cycle to work on my "Specialized Hard Rock" MTB. It's about 6 miles
    each way and I've been doing it since May 2003. Thankfully, all I've had
    to replace so far are some spokes -- I haven't even had a puncture yet!

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with a
    loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    As you can probably tell I'm no expert, so any help would be greatly
    appreciated.

    Regards,
    Donny

  2. Donny said:

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with a
    loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    Could be the gears are out of adjustment and just need a bijou tweakette
    of the cable tension. There's a threaded adjuster where the cable goes
    into the gear mech at the back, try undoing it a quarter turn and see if
    it makes any difference, if not try another quarter turn and so on. If
    this /isn't/ the problem then eventually all your other gears will get
    out of sync, so just return it to where it was to start with if this
    happens (so keep a note of how many quarter turns you did!)

    If it isn't that it's quite possibly a worn sprocket, though it's quite
    unusual for the wee one to go unless you're a terrible masher (someone
    who relies on higher gears and standing on the pedals more than is good
    for them or their bike, if this describes you then try spinning lower
    gears at a higher cadence).

    Completely unrelated to your question, but if you still have the
    off-road tyres on the bike then swapping them for some slicks will make
    it quite a bit easier to use on the road.

    Pete.
    --
    Peter Clinch Medical Physics IT Officer
    Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
    Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
    net [email hidden] http://www.dundee.ac.uk/~pjclinch/

  3. Peter Clinch said:


    Donny said:

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with a
    loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    Could be the gears are out of adjustment and just need a bijou tweakette
    of the cable tension. There's a threaded adjuster where the cable goes
    into the gear mech at the back, try undoing it a quarter turn and see if
    it makes any difference, if not try another quarter turn and so on. If
    this /isn't/ the problem then eventually all your other gears will get
    out of sync, so just return it to where it was to start with if this
    happens (so keep a note of how many quarter turns you did!)

    If it isn't that it's quite possibly a worn sprocket, though it's quite
    unusual for the wee one to go unless you're a terrible masher (someone
    who relies on higher gears and standing on the pedals more than is good
    for them or their bike, if this describes you then try spinning lower
    gears at a higher cadence).

    probably the other way around, a worn chain skipping on the little used
    sprockets. About par for the mileage

    Or the bike has fallen over causing the dropout & derailleur to bend
    inwards
    --
    ---
    Marten Gerritsen

    INFOapestaartjeM-GINEERINGpuntNL
    www.m-gineering.nl


  4. Quoted message said:

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with a
    loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?


    Maybe not enough chain tension or maybe the chain has stretched or
    worn badly. You've probably knocked up a fair few miles there. Are you
    a heavy rider? Lots of hills on route?

    You could try;

    1) Make sure there are no stiff links in the chain. Its a tighter bend
    with the smaller cog/higher rear gear. Clean/degrease then lubricate
    and make sure no stiff links.

    2) Making sure the wheel is as far back as possible in the frame
    dropouts.

    3) Make sure the rear cogs are nicely lined up with the front chainset
    and chain. Sometimes this means the wheel doesn't sit quite in the
    middle of the frame at the bottom bracket end but instead goes very
    slightly to one side or the other.

    4) There may be a deraileur screw adjustment near where the deraileur
    screws to the frame that can increase chain tension slightly.

    5) Replace chain and possibly cassette :-(

    6) Try a cheap bodge like removing 2 chain links to increase chain
    tension if you can get away with this (i.e. have enough play across
    the whole gear range to do this and chain may have slightly stretched
    with use).

  5. Peter Clinch said:
    Donny said:

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with
    a loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    Could be the gears are out of adjustment and just need a bijou tweakette
    of the cable tension. There's a threaded adjuster where the cable goes
    into the gear mech at the back, try undoing it a quarter turn and see if
    it makes any difference, if not try another quarter turn and so on. If
    this /isn't/ the problem then eventually all your other gears will get
    out of sync, so just return it to where it was to start with if this
    happens (so keep a note of how many quarter turns you did!)

    The problem used to only happen when it was wet and I tried this method
    last time it rained a lot. Unfortunately it didn't help!

    Quoted message said:


    If it isn't that it's quite possibly a worn sprocket, though it's quite
    unusual for the wee one to go unless you're a terrible masher (someone
    who relies on higher gears and standing on the pedals more than is good
    for them or their bike, if this describes you then try spinning lower
    gears at a higher cadence).

    I never stand on the pedals but I do use the highest gear about 90% of
    the time.

    Quoted message said:


    Completely unrelated to your question, but if you still have the
    off-road tyres on the bike then swapping them for some slicks will make
    it quite a bit easier to use on the road.

    Yeah, I've got 1.75 inch road tyres. I really should have bought a road
    bike but it's too late now!

    Quoted message said:


    Pete.

  6. Martin Wilson said:
    Quoted message said:

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with a
    loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    Maybe not enough chain tension or maybe the chain has stretched or
    worn badly. You've probably knocked up a fair few miles there. Are you
    a heavy rider? Lots of hills on route?

    In answer to these questions: I've probably done over 4000 miles, I'm
    about 14 stone, there aren't really any hills, and I use top gear most
    of the time.

    Quoted message said:


    You could try;

    1) Make sure there are no stiff links in the chain. Its a tighter bend
    with the smaller cog/higher rear gear. Clean/degrease then lubricate
    and make sure no stiff links.

    Sounds like a goer, I'll give this a try.

    Quoted message said:


    2) Making sure the wheel is as far back as possible in the frame
    dropouts.

    What are frame dropouts?

    Quoted message said:


    3) Make sure the rear cogs are nicely lined up with the front chainset
    and chain. Sometimes this means the wheel doesn't sit quite in the
    middle of the frame at the bottom bracket end but instead goes very
    slightly to one side or the other.

    The largest cog at the front is in line with the second smallest at the
    back.

    Quoted message said:


    4) There may be a deraileur screw adjustment near where the deraileur
    screws to the frame that can increase chain tension slightly.

    5) Replace chain and possibly cassette :-(

    6) Try a cheap bodge like removing 2 chain links to increase chain
    tension if you can get away with this (i.e. have enough play across
    the whole gear range to do this and chain may have slightly stretched
    with use).

  7. Martin Wilson said:

    Maybe not enough chain tension or maybe the chain has stretched or
    worn badly. You've probably knocked up a fair few miles there. Are
    you a heavy rider? Lots of hills on route?

    The chain almost certainly has stretched, but this has nothing to do
    with the weight of the rider or the amount of hill climbing done.
    Stretching is caused by wear at the rollers and is accelerated by
    lubricating a dirty chain. The plates of the chain do not themselves
    stretch significantly.

    Quoted message said:

    1) Make sure there are no stiff links in the chain. Its a tighter
    bend with the smaller cog/higher rear gear. Clean/degrease then
    lubricate and make sure no stiff links.

    Good advice. A stiff link is a possibility. You can generally ease it
    by grasping the chain firmly either side of the stiff link and flexing
    the chain hard sideways in both directions.

    Quoted message said:

    2) Making sure the wheel is as far back as possible in the frame
    dropouts.

    I'd be very surprised if the OP's bike has horizontal dropouts.

    Quoted message said:

    5) Replace chain and possibly cassette :-(

    If the chain needs replacing the cassette definitely will. A new chain
    on a worn cassette will skip like mad.

    Quoted message said:

    6) Try a cheap bodge like removing 2 chain links to increase chain
    tension if you can get away with this (i.e. have enough play across
    the whole gear range to do this and chain may have slightly stretched
    with use).

    This is risking damage if the rider selects the big/big combination,
    which admittedly he shouldn't do. If the chain has stretched that much
    then both it and the cassette need replacing.

    --
    Dave...

  8. Donny popped their head over the parapet saw what was going on and said

    Quoted message said:
    Quoted message said:

    Recently the gears have started acting up: when I'm using the


    smallest

    Quoted message said:

    cog on the cassette the pedals will "jump" about 1/8th of a turn with
    a loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    4,000 miles and never a new chain/cassette, is the small cog worn at
    all
    (shark finning of the teeth) has the chain stretched? If either of
    these
    apply maybe it's time to think of new ones .
    Alternatively you could try adjusting the rear derralieur cable (Mmm
    seems you tried that already) have you laid/dropped the bike down on
    the drive side? The actual rear derailleur may be bent in which case no
    amount of "adjusting/tweaking" will do any good. One thing if all this
    seems correct, are the cones in your rear wheel OK, that too will negate
    any "adjusting/tweaking"?
    All the above is just some things to think about, I am no chain
    expert.

    --
    yours S

    Nihil curo de ista tua stulta superstitione

  9. Donny said:

    I never stand on the pedals but I do use the highest gear about 90% of
    the time.

    The sprocket and chain is probably worn out--you've got the classic
    symptoms. Replace both the cassette and chain if none of the adjustments
    and checks work. The chainrings (sprockets at the front) will be ok with
    a new chain, with a bit of luck.

    Quoted message said:
    Quoted message said:

    Completely unrelated to your question, but if you still have the
    off-road tyres on the bike then swapping them for some slicks will
    make it quite a bit easier to use on the road.

    Yeah, I've got 1.75 inch road tyres. I really should have bought a
    road bike but it's too late now!

    Not too late for Schwalbe Jets from www.wiggle.co.uk

    ~PB

  10. "Pete Biggs" <[email hidden]> wrote in message
    news:[email hidden]...

    Quoted message said:
    Donny said:

    I never stand on the pedals but I do use the highest gear about 90% of
    the time.

    The sprocket and chain is probably worn out--you've got the classic
    symptoms. Replace both the cassette and chain if none of the adjustments
    and checks work. The chainrings (sprockets at the front) will be ok with
    a new chain, with a bit of luck.

    Quoted message said:
    Quoted message said:

    Completely unrelated to your question, but if you still have the
    off-road tyres on the bike then swapping them for some slicks will
    make it quite a bit easier to use on the road.

    Yeah, I've got 1.75 inch road tyres. I really should have bought a
    road bike but it's too late now!

    Not too late for Schwalbe Jets from www.wiggle.co.uk

    ~PB

    If you are using top gear a lot there are two obvious things to check. One
    is your cadence; it's generally reckonned that the higher cadence you can
    sensibly manage the better it is for your knees - I aim for 95 rpm but if
    I'm off-form struggle to do 85. The second idea is to look at the cassete
    your'e using - especially as like Pete I suspect you need a new one - and
    look at getting one with a smaller small sprocket to give you a higher top
    gear.

    HTH
    Julia

  11. Donny said:

    Hi there,

    I'm new to this forum, so hello everyone!

    I cycle to work on my "Specialized Hard Rock" MTB. It's about 6 miles
    each way and I've been doing it since May 2003. Thankfully, all I've
    had to replace so far are some spokes -- I haven't even had a
    puncture yet!

    Recently the gears have started acting up: when I'm using the smallest
    cog on the cassette the pedals will "jump" about 1/8th of a turn with
    a loud clunk. Could this been a problem with the chain or with the
    cassette (or both), or something else altogether?

    As you can probably tell I'm no expert, so any help would be greatly
    appreciated.

    I'd say new chain, new cassette (get an SRAM chain and cassette, not
    Shimano), and if the drive's still skipping, new chainrings. It sounds a
    decent bike, so hopefully it'll have seperate chainrings. If it's [censored],
    it'll have the chainrings riveted to the cranks and you'll need a new
    crankset.

  12. dkahn400 said:
    Martin Wilson said:

    Maybe not enough chain tension or maybe the chain has stretched or
    worn badly. You've probably knocked up a fair few miles there. Are
    you a heavy rider? Lots of hills on route?

    The chain almost certainly has stretched, but this has nothing to do
    with the weight of the rider or the amount of hill climbing done.
    Stretching is caused by wear at the rollers and is accelerated by
    lubricating a dirty chain. The plates of the chain do not themselves
    stretch significantly.

    Nothing to do with the weight of the rider and amount of hill
    climbing?!

    How do you work that out as it seems totally illogical. For a start
    the chain would be under greater tension and would snap into the
    sprocket grooves with greater force as it goes round because the
    tension is greater and this would cause more wear to the rollers. I'll
    admit the wear and tear is also heaviliy related to how the bike is
    ridden and what gears are selected but it makes no sense to me to say
    its not related to weight or hill climbing.

    Your statement seems totally incorrect.

    Quoted message said:
    Quoted message said:

    1) Make sure there are no stiff links in the chain. Its a tighter
    bend with the smaller cog/higher rear gear. Clean/degrease then
    lubricate and make sure no stiff links.

    Good advice. A stiff link is a possibility. You can generally ease it
    by grasping the chain firmly either side of the stiff link and flexing
    the chain hard sideways in both directions.

    Quoted message said:

    2) Making sure the wheel is as far back as possible in the frame
    dropouts.

    I'd be very surprised if the OP's bike has horizontal dropouts.

    Fair enough I made the point just in case it did as lots of bikes do
    near the bottom end of pricing and don't know the OP's specific bike.

    Quoted message said:
    Quoted message said:

    5) Replace chain and possibly cassette :-(

    If the chain needs replacing the cassette definitely will. A new chain
    on a worn cassette will skip like mad.

    You obviously live in a world where chains don't rust or have stiff
    links that can't be freed up. There are times when a chain needs to be
    replaced because only the chain is at fault. You don't need to replace
    a cassette because your chain has permanent stiff links.

    Quoted message said:
    Quoted message said:

    6) Try a cheap bodge like removing 2 chain links to increase chain
    tension if you can get away with this (i.e. have enough play across
    the whole gear range to do this and chain may have slightly stretched
    with use).

    This is risking damage if the rider selects the big/big combination,
    which admittedly he shouldn't do. If the chain has stretched that much
    then both it and the cassette need replacing.

    If you've already checked that it would be ok before removing the
    links as suggested then you shouldn't have any problems afterwards.

    I have to say that I think the OP probably has a fairly common problem
    because mountain bikes used on the road often face a lack of fast
    gearing so you end up riding 60-70% of the time in the same gear.

    He may have worn out the smallest sprocket on his cassette and chain
    and nothing else. I don't know if he's fortunate enough to be able to
    replace individual sprockets but if so he could probably get away with
    just replacing the smallest sprocket.

    If he does have to replace the whole cassette now would be time to get
    a better range of gears. Possibly his existing cassette has 13 or 12
    teeth on its smallest sprocket and he should definitely think about
    getting one with 11 teeth at the bottom end. He'll go a bit faster and
    enjoy cycling a bit more and save himself a bit of time. Perhaps with
    the time saved he can do a bit of overtime to help pay for the
    upgrade.

  13. Martin Wilson said:

    On 8 Dec 2004 06:34:13 -0800, "dkahn400" <[email hidden]> wrote:

    Quoted message said:
    Quoted message said:

    The chain almost certainly has stretched, but this has nothing to do
    with the weight of the rider or the amount of hill climbing done.
    Stretching is caused by wear at the rollers and is accelerated by
    lubricating a dirty chain. The plates of the chain do not themselves
    stretch significantly.

    Nothing to do with the weight of the rider and amount of hill
    climbing?!

    How do you work that out as it seems totally illogical. For a start
    the chain would be under greater tension and would snap into the
    sprocket grooves with greater force as it goes round because the
    tension is greater and this would cause more wear to the rollers. I'll
    admit the wear and tear is also heaviliy related to how the bike is
    ridden and what gears are selected but it makes no sense to me to say
    its not related to weight or hill climbing.

    Your statement seems totally incorrect.

    From <http://draco.acs.uci.edu/rbfaq/FAQ/8d.2.html>.

    :At the outset the term "chain stretch" is technically wrong and
    :misleading. Chains do not stretch, in the dictionary sense, by
    :elongating the metal through tension. They lengthen because their
    :hinge pins and sleeves wear which is caused almost exclusively by
    :road grit that enters the chain when oiled.

    Quoted message said:
    Quoted message said:

    If the chain needs replacing the cassette definitely will. A new chain
    on a worn cassette will skip like mad.

    You obviously live in a world where chains don't rust or have stiff
    links that can't be freed up. There are times when a chain needs to be
    replaced because only the chain is at fault. You don't need to replace
    a cassette because your chain has permanent stiff links.

    If it was just a stiff link then neither the chain nor the cassette
    would have needed changing. With the chain already skipping it
    possible, but highly unlikely, that he could have got away with just a
    change of chain.

    Quoted message said:

    I have to say that I think the OP probably has a fairly common problem
    because mountain bikes used on the road often face a lack of fast
    gearing so you end up riding 60-70% of the time in the same gear.

    He may have worn out the smallest sprocket on his cassette and chain
    and nothing else. I don't know if he's fortunate enough to be able to
    replace individual sprockets but if so he could probably get away with
    just replacing the smallest sprocket.

    I agree that mountain bikes are often unsuitably geared for the road.
    The OP is either pushing too high a gear, or his bike is under-geared
    for road use, or possibly a bit of both.

    --
    Dave...

    Get a bicycle. You will not regret it. If you live. - Mark Twain


  14. Quoted message said:
    Quoted message said:

    Nothing to do with the weight of the rider and amount of hill
    climbing?!

    How do you work that out as it seems totally illogical. For a start
    the chain would be under greater tension and would snap into the
    sprocket grooves with greater force as it goes round because the
    tension is greater and this would cause more wear to the rollers. I'll
    admit the wear and tear is also heaviliy related to how the bike is
    ridden and what gears are selected but it makes no sense to me to say
    its not related to weight or hill climbing.

    Your statement seems totally incorrect.

    From <http://draco.acs.uci.edu/rbfaq/FAQ/8d.2.html>.

    I've read it, I don't agree with it and I don't care who wrote it, not
    that the article actually states there is no connection with load only
    that its almost exclusively related to grit and lubrication. Obviously
    it depends on what he means by 'almost entirely'. Is it 80% or 95% or
    98% I don't know but he has allowed for load in his statement. I
    actually work in a factory where we have chains as long as 30 metres.
    The longest being on a system where trolleys are pulled into a long
    oven after painting.

    I think the reality is a well lubricated and looked after chain will
    resist the effects of load better. That frankly is the point of the
    lubricant to stop bare metal rubbing hard against each other and
    causing heat and abrasion. However as we all know a lot of cyclists
    don't maintain their bikes at all and use them until they have to fix
    them and in that scenario load will have a far greater effect.

    I certainly can't accept that load is not significant and have years
    of experience in a factory environment where it simply isn't true to
    say that. Certainly theres a enough muck and dirt blowing about in the
    factory to simulate similar conditions to cycling. My point load is
    obviously a factor even if its only 5% although I would be surprised
    if its this low especially with regards heavier riders who are on the
    wrong side of 15 stone.

    Quoted message said:

    :At the outset the term "chain stretch" is technically wrong and
    :misleading. Chains do not stretch, in the dictionary sense, by
    :elongating the metal through tension. They lengthen because their
    :hinge pins and sleeves wear which is caused almost exclusively by
    :road grit that enters the chain when oiled.

    Quoted message said:
    Quoted message said:

    If the chain needs replacing the cassette definitely will. A new chain
    on a worn cassette will skip like mad.

    You obviously live in a world where chains don't rust or have stiff
    links that can't be freed up. There are times when a chain needs to be
    replaced because only the chain is at fault. You don't need to replace
    a cassette because your chain has permanent stiff links.

    If it was just a stiff link then neither the chain nor the cassette
    would have needed changing. With the chain already skipping it
    possible, but highly unlikely, that he could have got away with just a
    change of chain.

    So you've got a rusty old chain with stiff links all over the place
    but the sprockets are fine and show minimum wear and you don't just
    replace the chain but instead muck about cleaning it up and replacing
    links?

  15. Martin Wilson said:

    So you've got a rusty old chain with stiff links all over the place
    but the sprockets are fine and show minimum wear and you don't just
    replace the chain but instead muck about cleaning it up and replacing
    links?

    That was not the case with the OP's chain, at least if it had been
    like that I presume he might have mentioned it.

    --
    Dave...

    Get a bicycle. You will not regret it. If you live. - Mark Twain

  16. Martin Wilson said:
    Quoted message said:


    From <http://draco.acs.uci.edu/rbfaq/FAQ/8d.2.html>.

    I've read it, I don't agree with it and I don't care who wrote it, not
    that the article actually states there is no connection with load only
    that its almost exclusively related to grit and lubrication. Obviously
    it depends on what he means by 'almost entirely'. Is it 80% or 95% or
    98% I don't know but he has allowed for load in his statement.

    He desn't bother explaining every nuance in pedantic detail. I agree
    that in principle, increasing the load will increase the wear (tandems
    certainly wear out chains much faster than equivalent single bike
    usage). However, the difference between a clean and dirty chain is much
    much much more important - exactly how much more important is not clear
    to me, but a muddy MTB chain in typical UK conditions will wear far
    faster than a road tandem in the dry parts of the USA, even if the road
    tandem is a heavy team carrying a camping load up and down a lot of big
    hills.

    AIUI, the point that the FAQ is trying to make most clear is that "chain
    stretch" is not actually stretch at all in the true meaning of the word.

    James
    --
    If I have seen further than others, it is
    by treading on the toes of giants.
    http://www.ne.jp/asahi/julesandjames/home/

  17. in message <[email hidden]>, James Annan

    (') said:
    Martin Wilson said:
    Quoted message said:

    From <http://draco.acs.uci.edu/rbfaq/FAQ/8d.2.html>.

    I've read it, I don't agree with it and I don't care who wrote it,
    not that the article actually states there is no connection with load
    only that its almost exclusively related to grit and lubrication.
    Obviously it depends on what he means by 'almost entirely'. Is it 80%
    or 95% or 98% I don't know but he has allowed for load in his
    statement.

    He desn't bother explaining every nuance in pedantic detail. I agree
    that in principle, increasing the load will increase the wear (tandems
    certainly wear out chains much faster than equivalent single bike
    usage). However, the difference between a clean and dirty chain is
    much much much more important - exactly how much more important is not
    clear to me, but a muddy MTB chain in typical UK conditions will wear
    far faster than a road tandem in the dry parts of the USA, even if the
    road tandem is a heavy team carrying a camping load up and down a lot
    of big hills.

    Chains in totally enclosed chain cases, particularly in partial oil
    baths, last extraordinary lengths of time. I've seen chains no larger
    than bicycle chains on industrial equipment lasting with little
    adjustment for years of continual use. Timing chains on cars similarly
    last a very long time. By contrast, of course, the chain in a mountain
    bike used frequently in muddy conditions wears quickly however
    carefully and regularly you clean and relube it.

    This is why I'm interested in using gearboxes and fixed chain lines on
    mountain bikes - if you can get it to work efficiently, then you can
    enclose the chain, using the chain case as a structural element of the
    rear swing arm; and that will give you a much more reliable
    transmission.

    It is, in my opinion, undoubtedly dirt which is the main factor in
    bicycle chain wear.

    Quoted message said:

    AIUI, the point that the FAQ is trying to make most clear is that
    "chain stretch" is not actually stretch at all in the true meaning of
    the word.

    Indeed.

    --
    [email hidden] (Simon Brooke) http://www.jasmine.org.uk/~simon/

    [ This .sig subject to change without notice ]

  18. Simon Brooke said:

    Chains in totally enclosed chain cases, particularly in partial oil
    baths, last extraordinary lengths of time. I've seen chains no larger
    than bicycle chains on industrial equipment lasting with little
    adjustment for years of continual use. Timing chains on cars similarly
    last a very long time.

    1. The torque in those applications tends to be far less than that applied
    to bicycle chains.

    2. Enclosed bike chains are used on single gear and hub gear bikes--these
    chains naturally last longer than derailleur chains because of their size
    and chainlines.

    Quoted message said:

    By contrast, of course, the chain in a mountain
    bike used frequently in muddy conditions wears quickly however
    carefully and regularly you clean and relube it.

    One reason MTB drivetrains wear faster than road bikes' is that smaller
    chainrings and sprockets are used.

    Quoted message said:

    This is why I'm interested in using gearboxes and fixed chain lines on
    mountain bikes - if you can get it to work efficiently, then you can
    enclose the chain, using the chain case as a structural element of the
    rear swing arm; and that will give you a much more reliable
    transmission.

    It is, in my opinion, undoubtedly dirt which is the main factor in
    bicycle chain wear.

    I'm not totally convinced it's the main factor. Might be, but the issue
    seems far from clear to me as there are so many factors.

    ~PB

  19. Pete Biggs said:
    Quoted message said:

    It is, in my opinion, undoubtedly dirt which is the main factor in
    bicycle chain wear.

    I'm not totally convinced it's the main factor. Might be, but the issue
    seems far from clear to me as there are so many factors.

    You've just had it demonstrated to you why dirt must the main factor:
    compare the stress of a loaded tandem riding big hills in clean dry
    roads, to an MTB in muddy areas.

    James
    --
    If I have seen further than others, it is
    by treading on the toes of giants.
    http://www.ne.jp/asahi/julesandjames/home/

  20. James Annan said:
    Pete Biggs said:
    Quoted message said:

    It is, in my opinion, undoubtedly dirt which is the main factor in
    bicycle chain wear.

    I'm not totally convinced it's the main factor. Might be, but the issue
    seems far from clear to me as there are so many factors.

    You've just had it demonstrated to you why dirt must the main factor:
    compare the stress of a loaded tandem riding big hills in clean dry
    roads, to an MTB in muddy areas.

    James

    Take a look at the clydesdale forum over on mtbr.com and you'll find
    riders who have destroyed their gearing in one day because of the
    torque they have put into their gearing. There's also reports of
    excessive chain wear over normal weight riders. I can't believe anyone
    would be surprised by this. Personally I think your not firing on all
    cyclinders if you think load isn't a factor with regard chain and
    cassette wear even if its not the main factor but hopefully if you
    read some real world experiences you might think differently.

    If you can't find the relevant postings I'm sure I can find the
    subject headings for you.

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