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  1. #1
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    the beauty of DOS

    dang! this is purty, like a purty moufh
    Attached Images Attached Images

  2. #2
    pvd
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    very nice, but those do make it difficult to do a 2x2 with vertical dropouts.

    here's how I do 2x2: http://www.pvdwiki.com/index.php?title=PVD_Two-by-Two

  3. #3
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    Are those geriatric gnome pubes all over that thing?
    owner/raconteur at fat-bike.com

  4. #4
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    might be

    Quote Originally Posted by ~gomez~
    Are those geriatric gnome pubes all over that thing?
    its that stuff form that felt-ish pad on the inside of the box...rather, gnome box.

  5. #5
    HIYAH
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    Quote Originally Posted by pvd
    very nice, but those do make it difficult to do a 2x2 with vertical dropouts.

    here's how I do 2x2: http://www.pvdwiki.com/index.php?title=PVD_Two-by-Two
    Yup, your way is much better....
    TTHHHHHHHHHPPPPPPPPPTTTTTTTTTTTTTTT

  6. #6
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    Quote Originally Posted by pvd
    very nice, but those do make it difficult to do a 2x2 with vertical dropouts.

    here's how I do 2x2: http://www.pvdwiki.com/index.php?title=PVD_Two-by-Two
    What's the difference?

  7. #7
    one chain loop
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    Quote Originally Posted by Nater
    What's the difference?
    look closely.
    everything sucks but my vacuum cleaner.

  8. #8
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    PVD... ENO has a matching crank with 2 gears as well, to keep the chain the same length the same, and keep a nice chain line.

    but if you did use alone, with a single crank gear, using an eccentric ENO rear hub with vert drops would be just fine.
    Ibis Tranny 29


  9. #9
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    Quote Originally Posted by fishcreek
    look closely.
    Still don't see it...he's using a cassette hub?

    Edit: See above...it's designed to be used with a crankset with 2 rings differing by the same number of teeth also. It just threads onto a threaded SS hub instead of a converted cassette hub.

  10. #10
    one chain loop
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    yes, and spacers. the advantage of it is having to run your own gear combo and not stuck with DOS's 16/18 and 17/19 freewheel.
    everything sucks but my vacuum cleaner.

  11. #11
    is buachail foighneach me
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    Quote Originally Posted by ernesto_from_Wisconsin
    its that stuff form that felt-ish pad on the inside of the box...rather, gnome box.

    well? is the felt made from geriatric gnome pubes or what?

  12. #12
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    Quote Originally Posted by ernesto_from_Wisconsin
    dang! this is purty, like a purty moufh
    I'd love to hear you're explanation at the emergency room. "I slipped and fell on it nurse....."

  13. #13
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    Quote Originally Posted by ernesto_from_Wisconsin
    dang! this is purty, like a purty moufh
    That's a nice looking device, but the question is.....does it squeal like a pig?
    Wanted: broken Titec 2 bolt seatpost, any size

  14. #14
    pvd
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    Quote Originally Posted by Mallanaga
    ENO has a matching crank with 2 gears as well, to keep the chain the same length the same, and keep a nice chain line.
    Are you sure about this? What are the gear ratios? Are they even usable?

  15. #15
    igoslo
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    Quote Originally Posted by pvd
    Are you sure about this?
    Yes.

    Quote Originally Posted by pvd
    What are the gear ratios?
    ENO Dos chainring comes in 35/38, freewheel comes in 16/18 and 17/19

    Quote Originally Posted by pvd
    Are they even usable?
    I guess that depends on the rider.

  16. #16
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    Quote Originally Posted by SoloRider
    Yes.
    ENO Dos chainring comes in 35/38, freewheel comes in 16/18 and 17/19
    For the Double-Double setup, a 16/19 freewheel is used in the rear with the 35/38 front. Only $370! ...

  17. #17
    pvd
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    Quote Originally Posted by SoloRider
    You may want to double check your math. Those combo's do not work with vertical dropouts.

    see: http://www.pvdwiki.com/index.php?tit...th_Calculation

  18. #18
    igoslo
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    Quote Originally Posted by pvd
    You may want to double check your math. Those combo's do not work with vertical dropouts.

    see: http://www.pvdwiki.com/index.php?tit...th_Calculation
    Aah, vertical drops, no tensioner, missed your first post. Minimal adjustment on any normal SS without needing two chains. How much need is there for 2x2 on non-SS frames anyway? For example your 2x2 wiki bike would work just fine w/ an ENO Dos setup.

  19. #19
    pvd
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    Quote Originally Posted by SoloRider
    For example your 2x2 wiki bike would work just fine w/ an ENO Dos setup.
    but then i would need tools to change gears. this is my point, I only need to use my QR to change gears. I do not need to change axle positions. you cannot do this with the DOS product.

  20. #20
    igoslo
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    Quote Originally Posted by pvd
    but then i would need tools to change gears. this is my point, I only need to use my QR to change gears. I do not need to change axle positions. you cannot do this with the DOS product.
    I don't run 2x2 and don't think I ever will, but I never find myself without tools and since it takes me less than a minute to reset chain tension, I still don't see the need. Also, 30x19 seems a bit insane as a SS gear to me(not that I'm really into the ENO Dos gear choices either), but if it works for you than that's fine.

  21. #21
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    PVD... you aggravate me. ENO make an eccentric rear hub. think EBB only built into the rear hub. so yes... those gear ratios would work... and then some.



    also... why wouldn't those ratios work? +3 -3 even if you didn't have the eccentric hub, that would keep your chain spot on the same length (your math is fuzzy. who cares about 2 hundredths of an inch... seriously ). i ain't past the bar, but i know a little bit...
    Ibis Tranny 29


  22. #22
    pvd
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    Those eccentric hubs are a total joke. They remind me of the 'isolator Hubs' of the early ninties. ha ha.

    The question remains, why pay more to do DOS wrong?

  23. #23
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    I can do a Dingle setup with no tools without changing the axle position with any gear ratio as long as it is the same difference. I don't know why you can't. I mean, just get some Tugg-Nuts with the QR washer, set your chain tension using the track ends, then just pop the wheel on and off. Or have sliders to tension the chain. Neither would require setting up the chain tension again and would be compatible with any ratio with any chainstay length.

  24. #24
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    [quote=pvd]Those eccentric hubs are a total joke. They remind me of the 'isolator Hubs' of the early ninties. ha ha. quote]

    Elaborate. I've had one since they came out and it is just now needing new berrings and has worked flawlessly. It gives folks the opertunity to turn a conventional frame w/ vertical dropouts into a ss without using a tensioner. The only flaw is that it changes the frames pitch slightly, but never to a point that it affects how I ride. Thats a very minor thing compared to what you get out of it. And "Isolator" hubs we're nothing of the sort.

    And I would have never gotton into an activity that involved a little "having to make adjustments" every once and a while. I mean you spend hours upon days trying to perfect some new widget, but seem to have an issue spending 30 seconds making a minor adjustment.

  25. #25
    mudnthebloodnthebeer
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    I think that I speak for everyone on the planet when I say that I wish I were as wise as pvd.
    Also, the streets are full of horizontal dropouts...

    BSNYC

  26. #26
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    Quote Originally Posted by pvd
    but then i would need tools to change gears. this is my point, I only need to use my QR to change gears. I do not need to change axle positions. you cannot do this with the DOS product.
    If the only real difference is QR versus bolt on...you can put the DOS freewheel on a QR thread-on SS hub and change gears without tools. Assuming a frame with sliding dropouts like the one you have pictured, or an EBB. Then the DOS ENO set-up works just fine on the trail...without tools.

    The limited gear ratios is another story...

  27. #27
    one chain loop
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    Quote Originally Posted by Mallanaga
    also... why wouldn't those ratios work? +3 -3 even if you didn't have the eccentric hub, that would keep your chain spot on the same length (your math is fuzzy. who cares about 2 hundredths of an inch... seriously ). i ain't past the bar, but i know a little bit...
    I'm sorry but I think you need exactly a half-link to achieve +3/-3 tooth difference to make it SPOT ON.
    everything sucks but my vacuum cleaner.

  28. #28
    is buachail foighneach me
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    as an example, on that chart, let's take 32x18 and 35x15, a +3-3 combo. the difference in chainstay lengths for exact tension is about 6 hundredths of a centimeter, or .06cm. .06 x 2.54(cm-inch conversion) = .15". i think the amount of resultant slack from .15" would be acceptible and not be enough to directly cause a chain drop. but i could be wrong.

  29. #29
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    2 hundeths of an inch... like i said.

    it was my impression that as long as you add and subtract the same number of teeth, then you're good to go. is that not the rule of thumb to go by?

    this is not an exact science. what do you do when your chain stretches? how do you take that into consideration on your fancy charts. does it stretch linearly over time, or is it more of a log shape curve? wtf. 0.15"... is that total slack? as in 0.15 total for the chain, or distance from outer ring to outer ring. if it's the latter, than that 0.15 just turned into 0.075.

    this is bologna. this thread started all beautiful with some nice freewheels that E pulled out of his pants, and now we're arguing about fractions of a centimeter.

    [voice="Napoleon Dynamite"] gawd! idiots! [/voice]
    Ibis Tranny 29


  30. #30
    one chain loop
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    Quote Originally Posted by sean salach
    as an example, on that chart, let's take 32x18 and 35x15, a +3-3 combo. the difference in chainstay lengths for exact tension is about 6 hundredths of a centimeter, or .06cm. .06 x 2.54(cm-inch conversion) = .15". i think the amount of resultant slack from .15" would be acceptible and not be enough to directly cause a chain drop. but i could be wrong.
    your math is correct but you are looking at a different grid. like i said +3/-3 is a half link difference, that is more like a half inch of slack to me. and for a vertical dropout user not having the luxury of tensioning SPOT ON, that will be a nut buster. mallanaga, pardon me for showing the chart, it just saves lives sometimes and saves time guessing.
    Last edited by fishcreek; 01-14-2008 at 11:21 PM.
    everything sucks but my vacuum cleaner.

  31. #31
    is buachail foighneach me
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    .15" is equal to half an inch how?

  32. #32
    one chain loop
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    Quote Originally Posted by sean salach
    .15" is equal to half an inch how?
    i don't know where you got the 0.15" figure, the measurement in the graph is the chainstay length, not the actual chain length.
    everything sucks but my vacuum cleaner.

  33. #33
    pvd
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    Quote Originally Posted by Mallanaga
    it was my impression that as long as you add and subtract the same number of teeth, then you're good to go. is that not the rule of thumb to go by?
    Absolutely not. the math show that this is not the case at all.


  34. #34
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    it's fuzzy math. answer my questions before you go spouting out your formulas.
    Ibis Tranny 29


  35. #35
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    There is a difference between science and engineering. If you're a scientist Pi = 3.1415926535897932384626433832795... if you're an engineer Pi could be 4. It depends on what's required of the final product. In this case, the +/- the same teeth works but it isn't the exact same tension. So if you want to do a lot of math you can have slightly different ratios to achieve the same tension... or you can use the rule of thumb and have a **** hair difference in tension.

  36. #36
    pvd
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    Quote Originally Posted by Mallanaga
    answer my questions.
    ha ha. You think your the boss. ha ha.

  37. #37
    is buachail foighneach me
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    Quote Originally Posted by fishcreek
    i don't know where you got the 0.15" figure, the measurement in the graph is the chainstay length, not the actual chain length.

    the two gearing combinations i mentioned are both listed with the same length chain, 46"(links). the larger ratio, 35x15 would fit perfectly on a bike with 'chainstays' 0.15" shorter than the 32x18 would. you would have to get pvd or willsmith to do the math on how much slack there would be, but i don't think it would be enough to drop the chain. this is also assuming that your chainstays are correct for the 35x25, which would probably require right about 16.7".

  38. #38
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    I find in these instances, a magic unicorn does wanders.

  39. #39
    is buachail foighneach me
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    Quote Originally Posted by Treybiker
    I find in these instances, a magic unicorn does wanders.

    but where does it wanders, and why?

  40. #40
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    With dérailleur chains, 0.15" change in the chainstay length will definitely be enough to let the chain derail. You might get by with a fixie chain & cogs, but I doubt it.

    Rule of thumb for chain wear is 1/16" over a foot, and that is generous. How many times do you adjust your chain tension before you replace your chain? (for me, it's at least once, or the chain comes off). A chain is ~ 3' long, that a 3/16" wear limit, or 0.1875". Since the chain doubles back, so that is only a change of 0.094" in the chainstay. Basically a ~0.05" change and you chain comes off. Most people don't realize how little a change it take for a modern dérailleur chain to derail. And that is practice, not engineering.

    The DOS ENO (its a beauty, even with the geriatric pubic gnome hairs) was designed with the eccentric ENO hub in mind, which can easily cover a full inch of adjustment, so they picked gears that they thought were ideal, rather than gears with the smallest delta. And you have to remove the wheel to change ratios anyways. In practice, it's a system that is easy to use and it works. And it is good engineering. If you like to change gears, that is...

  41. #41
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    Quote Originally Posted by itsdoable
    If you like to change gears, that is...
    thank you. i suppose that answers the question at hand.

    SS ftw!
    Ibis Tranny 29


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