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  1. #1
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    Poor person's ENO

    Since I hate chain tensionser, and I like disc brakes, here is a modified Shimano axle that gives you ~5mm of eccentric motion and still lets you run discs.

    People have in the past filed flats into a solid nutted axle to achieve some chain tension adjustment - this give you about 2mm of adjustment. I've successfully done this with a shimano disc hub, and it works great, but you have to have a chainstay - chain ring combo that is "really" close.

    What I did to get more eccentricity was use the existing QR hollow axle, and grind off one side as shown:

    OK, so I was a bit sloppy with the grinder - if you want to preserve your lock nut, I would advise removing the axle or putting on a sacrificial lock nut.

    Here is another view with the QR axle going through it:


    This is what it looks like in the dropout:


    This setup allow me to run gear ratios from 1:45 to 2.125 on my 425mm chainstay (16.75"). For instance, the modified axle will work with the following chainring combinations - 32:22, 36:22, 34:20, 32:18, 40:22, 35:19,38:20, 33:17, 36:18, 34:16 - and a few others.

    As far as durability goes, it didn't break on it's first ride, or second, or 3rd, 4th, etc..., but longterm durability will have to wait. In anycase, if the axle breaks, it's a <$10 shimano part, no big deal. The nicest part is that my disc brake caliper & rotor clear with no modifications.

    Cheers,

    Tom

    {edited - OK, I think I've figured out how to handle pictures with the new board...}
    Last edited by itsdoable; 05-25-2006 at 08:39 AM. Reason: (re-insert pics...)

  2. #2
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    no axle at all

    i am gonna guess your durability remains pretty good. this is why:

    i have an alu road vert drop fixed gear that i made work by cutting off the axle ENTIRELY, outboard the cone nuts. there is nothing at all of the axle holding the bike up - nothing in the dropout at all save the QR skewer.

    i got the idea from sheldon brown, who sez that the force of the QR is stronger than the strength of the axle, and thus a really tight QR will hold up the bike as well as you please. i did not believe it either. and, i do carry a spare QR taped on the seattube. and, i use a really nice QR skewer - i think it is a XT.

    anyway, it works and thus far has not broken. i rode it a fair bit for a year now.

    mind you now, this is on the road and not a mt bike, but still. who knew? anyway, i was surprised, and just thought it was interesting. tim

  3. #3
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    whoa... those are really clear pics... what kind of camera are you using?

  4. #4
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    Thanks for sharing...

    I may try that if I ever get around to converting my AL hardtail (I filed my current steel frame).

    You've proven once again that you don't have to spend a ton of money to ride a Simple Speed. And I wouldn't call it a poor person's ENO - I would call it a resourceful person's ENO.

  5. #5
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    Quote Originally Posted by mon t
    i am gonna guess your durability remains pretty good. this is why:

    i have an alu road vert drop fixed gear that i made work by cutting off the axle ENTIRELY, outboard the cone nuts. there is nothing at all of the axle holding the bike up - nothing in the dropout at all save the QR skewer.

    i got the idea from sheldon brown....
    Yes, I was aware of the Sheldon Brown article about filing down the axle to the locknut. In that case, if the QR broke, you are more likely to damage the rotor or caliper as there would be nothing keeping the wheel in place. By filing 1/2 axle, you get the same range of adjustment, and it makes lining up the wheel & rotor with the caliper much easier.

    I think the most likely way the axle would break is if the QR was loose and the full load was applied to the filed axle ends. Personally I think it will hold up fine for me, but there are some people in our ride group that will break just about anything...

    Cheers,

    Tom
    Last edited by itsdoable; 01-25-2004 at 03:50 PM.

  6. #6
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    Quote Originally Posted by Grimey
    whoa... those are really clear pics... what kind of camera are you using?
    3 year old Sony F505 in macro mode...

  7. #7
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    well again, retch - this is a pretty limited deal. you buy only 2-3 mm of adjustment. say 4 if you file the whole axle off like i did. you gotta be pretty close to start. tim

  8. #8
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    Quote Originally Posted by mon t
    well again, retch - this is a pretty limited deal. you buy only 2-3 mm of adjustment. say 4 if you file the whole axle off like i did. you gotta be pretty close to start. tim
    For the most part, I agree, however I can get a little over 5mm of adjustment out of this setup. If you are willing to use chainrings up to 44t and cogs upt to 22t (I run a 44:22 on a cruiser type frame) you always have a choice of gear ratios in the 1:1.5 ~ 1:2 range. Now if you also file your dopouts a bit... - with some pre-planing and careful selection of chainrings & cogs, I think you can always get a ratio that is acceptable. But like you said, if it's close to something you want to start with, it works better.

    Cheers,

    Tom

  9. #9
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    Good job! Well try this

    [SIZE="3"]Why Not:

    File a slot in the frame and use a bolt on skewer?

    [/SIZE]
    [SIZE=3] Proformance Cycle[/SIZE]
    proformance58@cs.com

  10. #10
    Paste eater
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    why not just grind the frame a few mm's?

  11. #11
    Gone riding
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    Holy flashback batman!

    I’d much rather cut a cheap axle then file / hack / cut a nice frame.

    Dave.

  12. #12
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    Good job!

    Quote Originally Posted by Low_Rider
    Holy flashback batman!

    Id much rather cut a cheap axle then file / hack / cut a nice frame.

    Dave.
    [SIZE="3"] Nothing a little Alumaloy and a Propane torch couldn't fix! I'm sure you've see the infomercial!


    [/SIZE]
    [SIZE=3] Proformance Cycle[/SIZE]
    proformance58@cs.com

  13. #13
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    Quote Originally Posted by Proformance Cycle
    [SIZE="3"]Why Not:

    File a slot in the frame and use a bolt on skewer?

    [/SIZE]
    Been There, Done That.

    Some dropout don't have much material to file. Steel dropouts take a lot longer to file then an eccentric axle conversion. It's a lot harder to file the dropouts symmetrically than to trim the axle symmetrically. Once a dropout is filed, there is no going back, and there is less area for the hub to bite. Filed dropouts require you to alight the wheel when mounting. But it still works fine, especially if you have a fancy hub you don't want to hack.

    Replacement Shimano axles cost $10 new (or you can scrounge one from an old wheel) - so it's definitely the "Poor Person's" way to go.

    [SIZE="3"]Why the big bold font?[/SIZE]

    Cheers,

    Tom

  14. #14
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    Quote Originally Posted by itsdoable

    [SIZE="3"]Why the big bold font?[/SIZE]

    so you can hear him, duh...

  15. #15
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    Did you guys try to find the magic gear? I thought it would be harder than it was, but using a BMX Pintle chain I was able to run the first combo I tried. geared down the other day, added two teeth and a half link and was back in business.

    I'm going to go out on a limb and say that clamp pressure is not going to work on a mountain bike. The hub will move. Especially with disc brakes. (That's just my gameshow answer). Maybe I just can't wrap my mind around it.

    -M
    Mike Henderson, Dirty Hippy Mountain Biker and part owner of Jet Lites.

  16. #16
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    Quote Originally Posted by wolfy
    Did you guys try to find the magic gear? I thought it would be harder than it was, but using a BMX Pintle chain I was able to run the first combo I tried. geared down the other day, added two teeth and a half link and was back in business.
    I've found that you still need a bit of adjustment with a magic gear - to take up chain wear. A bit of wear, a bumpy section, and the chain is prone to derail.


    Quote Originally Posted by wolfy
    I'm going to go out on a limb and say that clamp pressure is not going to work on a mountain bike. The hub will move. Especially with disc brakes. (That's just my gameshow answer). Maybe I just can't wrap my mind around it.-M
    If you look at my original post, that was in 2004, and I'd already had a year on it. I've converted a half dozen Shimano hubs this way, and I personally still have 3 SS's using this conversion, all with disc brakes, 2 on a steel frame, one on a Ti. As long as you use a good skewer (preferably a Shimano version), the hub does not move.

  17. #17
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    I've had to do the same thing to get the magic gear on two of the SS bikes. This one was on a dinglespeed but you can see where the axle is a bit forward on the dropout. The hub was a Bontrager (DT240)...
    Attached Images Attached Images

  18. #18
    ^ The Trail Starts Here ^
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    Quote Originally Posted by itsdoable
    Been There, Done That.

    Some dropout don't have much material to file. Steel dropouts take a lot longer to file then an eccentric axle conversion. It's a lot harder to file the dropouts symmetrically than to trim the axle symmetrically. Once a dropout is filed, there is no going back, and there is less area for the hub to bite. Filed dropouts require you to alight the wheel when mounting. But it still works fine, especially if you have a fancy hub you don't want to hack.

    Replacement Shimano axles cost $10 new (or you can scrounge one from an old wheel) - so it's definitely the "Poor Person's" way to go.

    [SIZE="3"]Why the big bold font?[/SIZE]

    Cheers,

    Tom
    [SIZE="3"]Why Not? [/SIZE]
    [SIZE=3] Proformance Cycle[/SIZE]
    proformance58@cs.com

  19. #19
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    (Cast spell, Thread Revival!)

    Has anyone tried or have some insight on threaded axels?

    EDIT: my bad, retread the thread. But great alternative to an eccentric hub! I will do so after finals and be sure to remember to post initial and later reviews myself.
    Last edited by toezter; 05-12-2013 at 01:37 PM.

  20. #20
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    The gear I wanted was sooooo close but was just a bit too tight. Just took the threads off one side with a three corner file and now it is perfect. Great tip!
    Make friends with Pain and you will never ride alone.
    One Heart, One Soul, One Gear

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