Results 1 to 21 of 21
  1. #1
    On MTBR hiatus :(
    Reputation: Speedub.Nate's Avatar
    Join Date
    Dec 2003
    Posts
    9,145

    Speedhub COG removal for Bloody Knuckles!

    <font size="+1" color="#444444">Presenting some tips for Rohloff Speedhub owners who have
    careers as hand models, and can't afford any shaved skin.

    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-1.jpg">

    One of the Speedhub's worst traits is its threaded-on cog. Unlike a splined cassette,
    Herr Rohloff designed his sprocket to screw on like a lid onto a jar. With the decision
    obvious between "pedaling makes der sprocket <i>fester</i> (tighter)" and "pedaling
    makes der sprocket looser", us end users have been handed a difficult task come
    time for removal.

    For starters, <i>always</i> use a liberal amount of anti-seize compound on the
    threads of any cog you install on your Speedhub. Recently, Rohloff began applying
    anti-seize at the factory (to both stock & aftermarket cogs). However, there are a
    good many in service that have a bit of corrosion which, every day, grows the bond
    between cog and hub.

    <i><b>"Have you lubed your cog lately???"</i></b>
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-2.jpg">

    My cogs have been lubed and trouble-free... until last weekend, when my wife, a
    hammer and I together destroyed a Lifu chain whip and still couldn't budge the cog
    fused to her hub. It was time to get serious!

    Below are the <u>new</u> tools for the job! My minimum equipment list, if you will.

    The list is comprised of: (1) Leather work gloves (2) Park SR-2 chain whip, $27
    (2) 24mm combination wrench, $16 (4) Permatex anti-seize lubricant (5) Rear wheel
    QR skewer (6) Rohloff 8501 sprocket removal tool (7 - optional) Replacement cog
    (8) Fender washer (9) Twist tie.
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-3.jpg">

    The 24mm combo wrench and Park SR-2 replace an adjustable wrench and the Lifu
    chain whip. The leverage advantage of the SR-2 is obvious; the Craftsman wrench
    has narrower, flatter jaws than the adjustable wrench, making the next step easier.
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-10.jpg">

    The <b>First Rule of Busted Knuckle Prevention</b> is to not let your tools slip. To
    that end, use the QR skewer to make an adapter & washer sandwich...
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-4.jpg">

    ...and assemble everything on the hub like so.
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-5.jpg">

    This serves two purposes: It locks the Rohloff cog remover securely to the hub, and
    it clamps the wrench to the adapter!
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-6.jpg">

    <i><b>Schwinggg!</b> Yes?!?</i>
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-7.jpg">

    The same busted knuckle rule applies to the chain whip. To get as much chain wrap
    as you can, and to buy some insurance against it slipping, use the twist tie to hold
    the loose end of the chain against the tool. <i>Voila!</i> The twist tie doesn't carry
    any of the load and doesn't need to be very tight.
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-8.jpg">

    With everything (relatively) securely held in place, and with wrench & whip in some
    variation of a 10 & 2 orientation, slip on those gardening gloves and let it fly!

    Keep in mind that all the downward force should be directed to the chain whip. The
    24mm wrench is only leveraging the internals against free rotation. Any excessive
    pressure applied to the wrench is wasted, and will only stress the hub internals.
    Ideally, the box end of the wrench would be connected by a cable to the floor
    directly beneath it, and no downward force would be applied to it at all.

    So find a balance, lay off, whatever... but reef on the chain whip, not the wrench!
    <img src="http://www.booboodog.net/images/sh-cog/sh-cog-9.jpg">

    Eye on the prize! Not having to fret over slipping tools, this time 'round, the cog
    came off in seconds, with no assistance from wife nor hammer. Most excellent!
    </font>
    Last edited by Speedub.Nate; 12-04-2006 at 07:36 PM.
    speedub.nate
    ∑ MTBR Hiatus UFN ∑

  2. #2
    mtbr member
    Reputation: logbiter's Avatar
    Join Date
    Dec 2003
    Posts
    2,822
    what, no pics of bloody knuckles? I was hoping for something like those trainer/ninja hex wrench shots

    very nice tutorial, especially about just reefing on the chain whip.

    one of these days I hope to grab rohloff.


  3. #3
    Get your freak on!
    Reputation:
    Join Date
    Dec 2003
    Posts
    2,697
    Yet another one of your perfect informative tutorials! Great work and keep it up!


  4. #4
    On MTBR hiatus :(
    Reputation: Speedub.Nate's Avatar
    Join Date
    Dec 2003
    Posts
    9,145
    Quote Originally Posted by logbiter
    what, no pics of bloody knuckles? I was hoping for something like those trainer/ninja hex wrench shots
    Funny how few posts come up when you search the forums for "<a href="http://forums.mtbr.com/showthread.php?t=186481">ankle hex wrench</a>". Ewww!

    First time around on this cog, I was actually expecting busted chops from the rim suddenly giving, folding into a <i>Nate's Face</i> taco. Shoulda maybe put a Hannibal Lecter mask on, instead!

    If not that, certainly a hernia.
    speedub.nate
    ∑ MTBR Hiatus UFN ∑

  5. #5
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    496

    cog removal

    Nater,
    good advice for sure, as I had a b-t-h of a time removing a cog a while back.
    Hoever I had applied a little heat from a mini torch and tapped witha brass mallet to help "shock" the cog.

    If we could somehow convince rohloff to do a small engineering change to the driver/cog to go to a spline and lockring set up, and be able adapt the hubs already out there to the "new spline lockring" style

    Verndogger

  6. #6
    Reviewer/Tester
    Reputation: Rainman's Avatar
    Join Date
    Apr 2004
    Posts
    6,191

    Upset ohh yeah..been there, done that..

    Almost busted a valve trying to remove a cog from a Rohloff about a year ago.

    Like you, I "gotta-bigga-hammer" in the shape of a longer lever setup..


    Those Rolly cogs can be a b!tch to get off if they have been on there for a while.


    R.
    It is inevitable ...

  7. #7
    mtbr member
    Reputation:
    Join Date
    Sep 2006
    Posts
    172
    I was cussing Nate for a bit tonight and then I was singing his praises. I used the posted technique to break the cog loose and it finally worked. Greased it up with the anti seize and I feel better now. Skinned a knuckle but it was well worth it. Thanks Nate for the great tutorial.

  8. #8
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    665
    Quote Originally Posted by tat2niner
    Skinned a knuckle but it was well worth it.
    Hope it wasn't as bad as this guy:

    http://www.aspinock.com/7x10minilath...ing_injury.jpe

  9. #9
    mtbr member
    Reputation:
    Join Date
    Sep 2005
    Posts
    45
    Try pouring boiling water on the cog.. that worked for me..

  10. #10
    On MTBR hiatus :(
    Reputation: Speedub.Nate's Avatar
    Join Date
    Dec 2003
    Posts
    9,145
    Quote Originally Posted by ShaunW
    Try pouring boiling water on the cog.. that worked for me..
    Hmmm... interesting. I suppose warming it with a heat gun would have similar results, without the mess.
    speedub.nate
    ∑ MTBR Hiatus UFN ∑

  11. #11
    mtbr member
    Reputation: UN-COG-KNEE-TOE's Avatar
    Join Date
    Mar 2008
    Posts
    164

    Good job! Use a long lever

    I modified my Park SR-2 making it 48" long, I secure the Cog Removal tool with a Bolt on Skewer and then secure the wheel in a Large Heavy WILTON Vise. I find the Vise works better than a Box Wrench for me. As soon as i break the Cog free, i Quickly remove the wheel from the Vise, because you are working upside down, the Hub Oil WILL drip out when the Cog breaks loose as the Cog is part of the Oil Seal system and Holds the Oil in.
    The 48" Lever really makes EASY work of Cog removal, i was surprised just how Easy it was to Remove the cog this way, i can do it with 1 hand!
    I struggled for several years before i figured out a worthy procedure for doing this. There are quite a few worthy methods for cog removal, this one works best for me.
    Attached Thumbnails Attached Thumbnails Speedhub COG removal for Bloody Knuckles!-tool1.jpg  

    Speedhub COG removal for Bloody Knuckles!-tool2.jpg  

    Speedhub COG removal for Bloody Knuckles!-vise.jpg  

    Last edited by UN-COG-KNEE-TOE; 11-28-2009 at 11:23 PM.

  12. #12
    mtbr member
    Reputation: 1stiski's Avatar
    Join Date
    Dec 2007
    Posts
    270
    Great knowledge before my purchase of the Rohloff.
    2010 Surly, Curry "Pugs"
    Surly, Gray "Pugs" R.I.P.
    2010 HARO, Mary SS
    Kona "Deluxe" roadbike

  13. #13
    mtbr member
    Reputation: BIGfatED's Avatar
    Join Date
    Apr 2005
    Posts
    927
    I have decided to run my bike SS for the winter. Seems as if it would be a good idea to pull the cog off and maintenance the thread interface just because. Thanks for the heads up.

  14. #14
    mtbr member
    Reputation:
    Join Date
    Mar 2008
    Posts
    12
    Just discovered this thread and wish I had in 2006 when I first changed Rohloff cogs! I made my own chain whip about as long as UN-COG-KNEE-TOE's one (ooops put away the rulers!!!) from some old (BIG TOUGH PC1 SINGLESPEED) chain and an iron bar with 3 drilled holes.
    Like him I also clamp the Cog removal tool in a vice once I've clamped the sandwich of tool and speedhub together with the skewer - that way you don't need a wife. As we know, a Vice is cheaper than a Wife.
    I've used grease for anti-sieze but that wasn't good enough - does anyone have an opinion on the best stuff?

  15. #15
    mtbr member
    Reputation:
    Join Date
    Feb 2010
    Posts
    2

    Bust my Rohloff hub casing with first time removal of cog

    I wish I had read this thread before. Yesterday I tried to remove my first cog. Only have ridden 1300 km with my MTB when my dealer changed the chain. It hopped over the teeth like a frog over stepping stones.
    After having changed Maillard freewheels, Shimano and SRAM casettes for about 30 years I thought nothing of changing/turning the cog on my year-old Rohloff.

    Just after having chipped off the profile of the Hub-casing I learned that Mr. Rohloff had in his wisdom decided to fix the cog to the hub with a thread. How blatently stupid can you be!

    Making the best and most complicated internal hub gear in the world and than constructing the only part that needs frequent maintenance so idiotic! Hail Shimano/SRAM-Sachs and Campagnolo for their improvements over the old Pignon/Freewheel threaded fixation like Maillard.

    I was determined to buy a new touring bike for the holidays with a Rohloff, but now will stick to the old derailleur system. I just don't want to think about anything going bust (like only a cog....) in Poland or further. On every streetcorner you can get a derailleur and cassette fixed or newly installed. Try that with a Rohloff.....

    Rohloff only for MTB. IN wich it is great. Save the cogs.

    My cog is still not removed. Tomorow it will be at my dealers.

  16. #16
    mtbr member
    Reputation: itsdoable's Avatar
    Join Date
    Jan 2004
    Posts
    1,903
    Early on, I mangled the aluminium mating tabs for the cog tool on one of my hubs - but there is still enough material there for the tool to hold on if you are careful. Since then, I have not had any issues removing the cog with a standard chain whip and a wrench (and cog tool).

    I use copper based anti-seize. The hub threads are alumunium, so they can corrode against the steel cog and seize. However, the threads are not the same as the Maillard / freewheels, they have a much larger pitch, which prevents the cog from being jammed on too tight by pedal load.

    I originally thought the cog interface was a poor choice, but in retrospect, it is fine.

    If you replace the chain before it gets to 0.75% wear, the cog will last a long time - almost for ever. One of my cogs is pushing 8 years - and I've had cogs wear out in under a year when I've forgot to check the chain. At least you can flip the cog over to get more life.

    My main complaint about the hub is that, as delivered, it is prone to corrosion, especially if you ride in winter with salt. The steel screws (ie: on the torque arm plate) easily corrode into the aluminium hub, as do the cable adjusters. Removing all the steel & threaded parts and re-installing with copper-based anti-seize has made a huge difference. Aluminium-based anti-seize works almost as well, but does not last as long.

  17. #17
    mtbr member
    Reputation: vikb's Avatar
    Join Date
    Sep 2008
    Posts
    10,531
    Thanks for a great post.... ...I put a link up to it on my blog and I'll be removing my Rohloff cogs this summer to make sure they don't become permanent!...
    Safe riding,

    Vik
    www.vikapproved.com

  18. #18
    mtbr member
    Reputation:
    Join Date
    Feb 2010
    Posts
    2
    Quote Originally Posted by itsdoable
    If you replace the chain before it gets to 0.75% wear, the cog will last a long time - almost for ever. One of my cogs is pushing 8 years - and I've had cogs wear out in under a year when I've forgot to check the chain. At least you can flip the cog over to get more life.
    I'll try this. The renewal of the cog is cumbersome to say the least. I have brought the bike to my dealer and he concluded that I was mentally still in the Shimano-mode: I had pushed the wrong way. I had not interpreted the manual wrong, or you can say, I didn't read it well enough. I was under the impression I had to release a lock-ring, so instead of trying to release my Rohloffs cog I fastened it, so damaging the mated teeth of the hub.
    My dealer has released the cog the right way and replaced or flipped it.

    I feel utterly stupid and not at the same time. The design of the Rohloff is perpendicular to all the other systems on the market for over 2 decades. The cassette-system wasn't developed for fun only.
    Well, we'll just have to cope with this design flaw. The hub in itself is very nice to ride with.

  19. #19
    On MTBR hiatus :(
    Reputation: Speedub.Nate's Avatar
    Join Date
    Dec 2003
    Posts
    9,145
    FWIW, I'm working with a Nuvinci that uses thread-on BMX style freewheels. I anticipate the same issue.
    speedub.nate
    ∑ MTBR Hiatus UFN ∑

  20. #20
    mtbr member
    Reputation: itsdoable's Avatar
    Join Date
    Jan 2004
    Posts
    1,903
    Quote Originally Posted by Lazybiker
    The design of the Rohloff is perpendicular to all the other systems on the market for over 2 decades. The cassette-system wasn't developed for fun only.
    Well, we'll just have to cope with this design flaw. The hub in itself is very nice to ride with.
    Threaded cogs have been around longer than freewheels or cassettes, and are still used by fixies/track bikes. The chainwhip was originally designed to remove the cog, long before it was use to stabilize a cassette. However, it is an easy mistake to make these days. But I wouldn't call it a design flaw...


    Quote Originally Posted by Speedub.Nate
    FWIW, I'm working with a Nuvinci that uses thread-on BMX style freewheels. I anticipate the same issue.
    I have a current Nuvinci (post ATC) , and it comes with a splined freewheel interface, and a threaded-to-spline adapter. I think the ATC versions have a threaded interface, which would require a tool to remove the freewheel. I'm not sure how I'll remove the spline adapter from the freewheel, I'll probably need a DIY tool. You could just get a new adapter, they look pretty cheap (cast steel).

    I actually have a fixed cog on it right now (with a freewheel on a jack shaft). However, the hub itself will freewheel easily, even though it was not really designed to.

  21. #21
    Unhinged Aussie on a 29er
    Reputation: hunter006's Avatar
    Join Date
    Jan 2012
    Posts
    452
    I know this thread is over 10 years old now, but major fist bump for the guide. I used it to remove my cog yesterday.

    Speedhub COG removal for Bloody Knuckles!-tqojera.jpg

    Ignore the paracord, that was just a visual reminder to tell Kronk which way to pull the lever.

    I tried to do a few things at first, like attaching the paracord to my shoe and making it a literal anchor to the ground. None of those worked. In the end I ended up doing what I used to do when I was removing SS cogs on fixie hubs: repositioning the whip handle close to the handle of the box wrench so I could squeeze them together with my hands to loosen the cog. Still wouldn't come off. I also hit it with the heat gun once everything was together for about 45-60s, warming it up slightly since it was a reasonably cool day yesterday. Once I did the heat gun trick it came off with about 40-50 ft lbs of force - so a lot, but not an unattainable amount for a small woman to achieve. The other nice thing about using the "squeeze together" technique is you can ease the cog and wrench off the hub internals together and then squeeze, so you don't have to worry about damaging the hub internals by accidentally applying force on the internals in the wrong way.

    Because of that I give this guide non-bloodied two thumbs up.

    The main differences to the OP and what I used yesterday is that the wrench and washer cost $5 combined (thank you Home Depot), and I used Park Tools ASC-1 anti seize compound and the Park Tools SR2.2 wrench instead. I'd also add 25 mL of Rohloff oil (no cleaning oil) to the list of items "optional" in case you spill the oil out when removing the cog.

    The only thing I would add to the procedure is to clean the hub engagement to the Rohloff cog tool very, very, very, VERY well. The tool should go all the way in, no gaps remaining. The first time I did this I screwed it up and had to send it to Cycle Monkey to fix it because the tool didn't mate with the splines properly due to a tiny bit of debris that was forcing the tool out. I thought it'd be fine but it wasn't.

Members who have read this thread: 4

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •