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  1. #26
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    From what I have read, heard and experienced personally I would say that track frames/parts are built stronger than road parts for various reasons, so I was surprised to see the photo of the imploded campag track hub, but it's true that locking up the rear wheel and skidding in the velodrome just doesn't happen unless something goes horribly wrong whereas on the street in a big city it happens with surprising regularity unless the bike has been fitted with a brake, in which case the bike would not experience the same punishment as a brakeless bike, track or otherwise. Track bikes and "fixies" do go through the same punishment on the road if both are brakeless, hence my preference for 1/8 chain and chainrings. As stated earlier, I have seen a 3/32 chainring fail under severe braking with a thrown chain resulting. If the bike has a brake, 3/32 would do nicely I imagine.

    Also I liked what you said about the stresses incurred by headsets of road bikes when braking. Good point. What do you think about the track BB? Why is Campagnolo still making it and what is the difference been it and the road version?

    I've included the photo of the hub and below is link to the full letter.
    http://www.sheldonbrown.com/harris/record-track.html
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  2. #27
    semifreddo amartuerer 'nother's Avatar
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    Quote Originally Posted by landrover4
    [blah blah blah...]

    I've included the photo of the hub and below is link to the full letter.
    http://www.sheldonbrown.com/harris/record-track.html
    I'm glad you brought up Sheldon Brown. From the same source we have another tidbit debunking the "trackies-need-stronger-chains-because-trackies-are-stronger" myth:

    Quote Originally Posted by Sheldon Brown
    Block Chain

    An obsolete type of chain, formerly popular with track racers. Block chain had solid blocks as inner links, without rollers. It had a 1" pitch with 3/16" wide blocks, the same as the "skip link" roller chain that appeared on the market about 1930 to replace it.
    The remaining stock of block chain was coveted by track riders who believed it was the only chain strong enough to withstand their imagined strength. When the stock of block chains finally ran out in the late 1970's, it was replaced by 1/2" pitch 3/32" wide chain, as used with derailers, although track riders still prefer an 1/8" wide chain, believing they are stronger than other riders. MTB's with 18 tooth granny chainwheels produce several times the chain tension any track rider can muster.
    see http://www.sheldonbrown.com/gloss_b.html, "Block Chain"
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  3. #28
    spinlikehell mickster's Avatar
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    Quote Originally Posted by 'nother
    I'm glad you brought up Sheldon Brown. From the same source we have another tidbit debunking the "trackies-need-stronger-chains-because-trackies-are-stronger" myth:
    No, trackies tend to prefer 1/8" width chains for a bunch of other reasons unrelated to strength:

    - They've less sideways flex, making them less likely to ship if chainline / tension is marginal.
    - They've 50% more width than a 3/32 chain and hence more metal in contact with the teeth of the chainring, meaning the drivetrain wears less quickly.
    - They are available with bushings unlike almost all 3/32 chains (and as far as I know all 9sp and 10 sp chains) - bushings make em run smoother and last longer than bushingless designs (a point made by Sheldon somewhere in his article I think)
    - They allow you to use both 1/8" and 3/32" sprockets and chainrings; this is not possible with a 3/32 chain. It makes swapping stuff with yr pals at the trackside easier, and you can take advantage of the considerable second-hand market in old track rings / sprockets when building yr collection of gears.

    Now this doesn't mean that a 3/32" chain can't be used at the track (cos they clearly can), or that you're in danger of snapping one through brute strength etc etc. It's just a question of which is better suited to the job. Put it another way, what material advantage is there by NOT going with 1/8" for the track, all other things being equal? The only one I can see is maybe cost...

    mickster

  4. #29
    semifreddo amartuerer 'nother's Avatar
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    Quote Originally Posted by mickster
    No, trackies tend to prefer 1/8" width chains for a bunch of other reasons unrelated to strength:
    I do not disagree with you and I did not mean it as any kind of "slam" on trackies; I was responding specifically to what landrover4 was saying:
    Quote Originally Posted by landrover4
    ...the stresses which come with this type of use. The chain, for example, is 1/8 inch instead of the thinner and weaker 3/32 inch of road bike...
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  5. #30
    Geek Extraordinaire sivat's Avatar
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    Quote Originally Posted by landrover4

    Also I liked what you said about the stresses incurred by headsets of road bikes when braking. Good point. What do you think about the track BB? Why is Campagnolo still making it and what is the difference been it and the road version?
    I don't know much about the campy bb, but I would imagine that a track bb undergoes more stress than a road bb. Since track bikes have only a single speed, in a sprint, or quick acceleration, I would think that pushing against the tall gear ratio on a track bike would be harder on the bb than sprinting through the gears on a road bike. The fact that some sprinters will use straps with thier clipless pedals on the track shows how much force is being put on the cranks and bb. I would say that smoothmess may have something to do with it as well. Because of the effiency of a fixed gear transmission, combined with the normally clean conditions of the track, track riders seem to be more concerned with a smooth drivetrain than road racers, who will use sealed bearings for better durability in sandy/dirty/wet conditions.

    As for what mickster said,
    -sideways flex just isn't an issue on a fixed gear. Unless your chainline is more that 2mm off, unheard of on any respectable track bike, there is no sideways force on the chain. If the chainline is off by that much, a more flexible chain would actually be better since it would be able to move more smoothly normal to the force of the chainwheel.
    -1/8 is 33% bigger than 3/32, not 50%.
    -Mixing 3/32 and 1/8, though possible, really defeats the purpose of running the bigger components.
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  6. #31
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    Great information. Thanks very much.

  7. #32
    spinlikehell mickster's Avatar
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    Quote Originally Posted by sivat
    As for what mickster said,
    -sideways flex just isn't an issue on a fixed gear. Unless your chainline is more that 2mm off, unheard of on any respectable track bike, there is no sideways force on the chain. If the chainline is off by that much, a more flexible chain would actually be better since it would be able to move more smoothly normal to the force of the chainwheel.
    -1/8 is 33% bigger than 3/32, not 50%.
    -Mixing 3/32 and 1/8, though possible, really defeats the purpose of running the bigger components.
    One of those perennials like whether to use lockrings, but I'll bite:
    I still maintain that sideways flex, or lack thereof, is a desirable characteristic in a track bike chain. Chainlines are not always spot on, even on 'repectable' track bikes - just run a pair of Mavic ellipse track wheels, for instance, on your otherwise respectable fully-Dura Ace pista equipped track bike and yr chainline is instantly 2mm off - and tolerances change as drivetrain parts wear. I also said that chain tension is a factor in this, and contend that a less-than-perfectly-adjusted chain is less likely to ship if it has less sideways flex as per a 1/8" track chain. If there was no sideways force involved on a track chain they wouldn't ever ship on the track, but we both know that this does occasionally happen.

    I said a 1/8 chain has 50% more width than a 3/32 - put another way, a 3mm chain has 50% more width than a 2mm chain. I think that statement still holds; in any case, we're into petty semantics - the point about it being wider and therefore longer lasting remains.

    mickster

  8. #33
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    Quote Originally Posted by mickster
    I said a 1/8 chain has 50% more width than a 3/32 - put another way, a 3mm chain has 50% more width than a 2mm chain. I think that statement still holds; in any case, we're into petty semantics - the point about it being wider and therefore longer lasting remains.

    mickster
    It's specious reasoning to make the analogy of 3mm and 2mm chain when refering to 1/8 chain and 3/32 chain. Better would be to say that 1/8 is to 4mm as 3/32 is to 3mm and therefore we see that 1/8 chain is neither 33% bigger/wider nor 50% bigger/wider but rather only 25% bigger/wider (choose your adjective).

    I'll end with an email from Sheldon Brown regarding track vs. road headsets and bottom brackets:

    Track stuff isn't generally going to be as well sealed as road stuff.

    Headsets have no effect on the bicycle's "ride"
    but track usage is much gentler on a headset,
    partly 'cause there's no dirt, partly 'cause
    there are no potholes.

    Track bottom brackets are commonly shorter than road bottom brackets.

    All the best,

    Sheldon


    So there you have it.

  9. #34
    spinlikehell mickster's Avatar
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    Quote Originally Posted by landrover4
    It's specious reasoning to make the analogy of 3mm and 2mm chain when refering to 1/8 chain and 3/32 chain. Better would be to say that 1/8 is to 4mm as 3/32 is to 3mm and therefore we see that 1/8 chain is neither 33% bigger/wider nor 50% bigger/wider but rather only 25% bigger/wider (choose your adjective). <snip>
    It'd be specious reasoning if I just pulled the 2mm/3mm figures out of thin air; however, they're frequently used as nominal metric equivalents when talking about 1/8 and 3/32 inch drivetrain width eg http://www.businesscycles.com/tr-refspec.htm#width.

    3 is 150% of 2. 2 is one third less than 3. Both statements are true.
    Like I said earlier, we're just p1ssing about with semantics.

    mickster

  10. #35
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    Quote Originally Posted by mickster
    It'd be specious reasoning if I just pulled the 2mm/3mm figures out of thin air; however, they're frequently used as nominal metric equivalents when talking about 1/8 and 3/32 inch drivetrain width eg http://www.businesscycles.com/tr-refspec.htm#width.

    3 is 150% of 2. 2 is one third less than 3. Both statements are true.
    Like I said earlier, we're just p1ssing about with semantics.

    mickster
    150%? I thought you said 50%? No matter, neither one comes into play when discussing how much larger 1/8 is to 3/32 or how much smaller 3/32 is to 1/8. However, regarding your numbers 3 and 2, yes, 3 is indeed 150% of 2 and 2 is one third less than 3, I agree 100%.

    To come back to the chain issue, my 25% is wrong if you're talking about how much wider 1/8 is compared to 3/32, but it is correct if you are talking about how much narrower 3/32 is compared to 1/8. But if you are talking strictly about how much larger/wider 1/8 is to 3/32, then the answer is 33%.

    1/8 = 4/32. 4/32 is 33% larger than 3/32. For example: 200 is 33% larger than 150. To increase the number 150 (3/32) to 200 (4/32) you need to add 33% of itself, or the number 50. (To reduce 200 to 150you need to remove 25% of itself.)

  11. #36
    cyclist/gearhead/cycli... moxfyre's Avatar
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    Quote Originally Posted by mickster
    No, trackies tend to prefer 1/8" width chains for a bunch of other reasons unrelated to strength:

    - They've less sideways flex, making them less likely to ship if chainline / tension is marginal.
    - They've 50% more width than a 3/32 chain and hence more metal in contact with the teeth of the chainring, meaning the drivetrain wears less quickly.
    - They are available with bushings unlike almost all 3/32 chains (and as far as I know all 9sp and 10 sp chains) - bushings make em run smoother and last longer than bushingless designs (a point made by Sheldon somewhere in his article I think)
    - They allow you to use both 1/8" and 3/32" sprockets and chainrings; this is not possible with a 3/32 chain. It makes swapping stuff with yr pals at the trackside easier, and you can take advantage of the considerable second-hand market in old track rings / sprockets when building yr collection of gears.
    No, Sheldon clearly explains that bushingless chains are more durable, and he believes this is because of better lubricant flow: http://www.sheldonbrown.com/chains.html ... this probably means that they run smoother too.
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  12. #37
    Geek Extraordinaire sivat's Avatar
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    Quote Originally Posted by mickster
    One of those perennials like whether to use lockrings, but I'll bite:
    I still maintain that sideways flex, or lack thereof, is a desirable characteristic in a track bike chain. Chainlines are not always spot on, even on 'repectable' track bikes - just run a pair of Mavic ellipse track wheels, for instance, on your otherwise respectable fully-Dura Ace pista equipped track bike and yr chainline is instantly 2mm off - and tolerances change as drivetrain parts wear. I also said that chain tension is a factor in this, and contend that a less-than-perfectly-adjusted chain is less likely to ship if it has less sideways flex as per a 1/8" track chain. If there was no sideways force involved on a track chain they wouldn't ever ship on the track, but we both know that this does occasionally happen.

    I said a 1/8 chain has 50% more width than a 3/32 - put another way, a 3mm chain has 50% more width than a 2mm chain. I think that statement still holds; in any case, we're into petty semantics - the point about it being wider and therefore longer lasting remains.

    mickster
    Why wouldn't you run a 4mm wider bb with the ellipses to keep the chainline? I don't buy it that there are track bikes racing with a chainline off by that much. Even so, with a chainline 2 mm off that mean that less than .5% of your pedaling force is pulling the chain sideways (assuming a 425mm chainstay length). A chain will only flex to the side if there is a force acting on it in that direction. That being said, if you put 200lbs of force on the pedals, and .5% of that is acting sideways on the chain, that 1 lb of force needs to be delt with. If the chain is perfectly rigid in that direction (which is impossible according to Einstein) that just means that it is going to be transfered directly to your chainring and cog teeth and wear them more quickly. Running a more flexible chain means that the force will be spread out and the drivetrain will last longer. Neither one will have an impact on how much force is transfered to the movement of the rear wheel. The fact is, 1/8th drivetrains are traditional on track bikes. Thats the main reason for running them. The chains are marginally stronger than 3/32 and may in fact give a slightly more responsive feel. Chains will only slip (and by this I assume you mean come off the chainwheel or cog) when something goes wrong. The chainwheel bends, the rear wheel moves in the fork ends, or something slips.
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  13. #38
    spinlikehell mickster's Avatar
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    sivat - you seem to be talking about *sideways force* on the chain in the sense of the sideways force that would be exerted via pedalling by virtue of the chain being misaligned; this isn't how chains ship (note the 'h') in my contention. IME they tend to ship because of looseness / misalignment / 'flapping about' which causes them to jump off a tooth, rather than because they're under a strong sideways force through pedalling. This looseness is a prerequisite, and as you say it can be caused by something slipping, or simply because the chain tension was not perfect to begin with. I'm suggesting that a laterally-stiffer bushinged (hence usually 1/8) chain will be more tolerant of such slippages / mistensioned chains and will be less easily thrown than a chain designed for sideways flexibility.

    And this stuff happens from time to time at the track - chainlines really aren't always perfect, trackies don't always fettle their BBs / chainlines to match a specific set of wheels / hubs (and in fact how could they as you tend to use several different rear wheels when racing / training), chains get tensiuoned imperfectly and sometimes they get shipped.

    On the 1/8-is-tradition point, I think we're in agreement; this is just a more general way of reiterating what I said about availability of used parts / ease of swapping and borrowing parts with other trackies.

    mickster

  14. #39
    Geek Extraordinaire sivat's Avatar
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    Ok, i'll bite. What is chain ship? I've never heard that term
    I'd rather have a bottle in front of me than a frontal lobotomy.

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