Tuesday, August 18, 2009

Cottered Crank Appreciation Society

I really like cottered cranks. The more I work with them, the more I like them. Maybe it's the contrarian in me, but I like that they are considered antiquated technology, and I like that most bike people have a low opinion of them, or don't have a clue about how they work. I like that they're slightly more complicated than they need to be, and I like the fact that they are also ridiculously simple. I like the collection of esoteric knowledge and the little tips and tricks that you pick up about working on them.

I've had three running conversations lately about working with stuck cotters and other finer points of cotter extraction. This, along with more experience, has made me want to update my "how to" posts about cottered cranks from last year (I'm not even going to link to them because I don't think they're very good). I'll be doing a new series of more detailed posts in the near future, but in the meantime, you are welcome to join my new Cottered Crank Appreciation Society. Our motto: "Oil it, clamp it, whack it."  

20 comments:

  1. Awesome. Check out this link - http://www.bikecult.com/works/chainwheel.html

    ReplyDelete
  2. Thanks. I'll look at Frankenbike's cottered crank (that has outlasted several cotterless variants) with a little more respect...

    ReplyDelete
  3. You need to know about this, if you don't:

    http://www.bikesmithdesign.com/CotterPress/index.html

    ReplyDelete
  4. They are usually so much better looking, too. I like fancy cranks and chain rings : )

    ReplyDelete
  5. @ Mike Jenkins: Thanks very much. I've bought cotters from Mark before, and he's a really nice guy, but I can't justify $50 for a cotter press that I can make myself out of a c-clamp and a socket wrench attachment. Maybe if I was removing cotters every day on a bunch of bikes, but I don't think most folks are.

    ReplyDelete
  6. I can't use cottered cranks personally, I'm too hard on stuff and need parts that are reliable and don't self destruct during maintainance. Too many stripped, bent, mushroomed cotters. But i'm all for luddite nostalgia, and I agree that this piece of arcana is worth notice and appreciation.

    ReplyDelete
  7. @Anonymous: I hope that my upcoming post on a DIY cotter press helps with the self-destructing part somewhat. There's no reason a properly installed and extracted cotter pin should be destroyed in the process of regular maintenance. Stay tuned...

    ReplyDelete
  8. Thom, dont knock (pun intended) your previous cotter posts--they were informative and useful

    ReplyDelete
  9. I use Mark (BikeSmithDesign)Stonich's cotter press and if you have to do more than a cotter or two it is well worth the money. I did a quick count this morning and I currently have over a dozen bikes that use cottered cranks. Decent quality replacement cotters have all but disappeared from the face of the earth, so getting the old ones out in one piece is critical, the cotter press does so.

    Another issue is removing cotters that have been in place since LBJ was office(or possibly even Eisenhour), the press does an outstanding job of perserving them. I also purchased Mark's fixed cup removal tool, again you don't realize what you are missing until you use it.

    Tools can be expensive, but not as expensive as having to locate hard to find replacement parts.

    Aaron

    ReplyDelete
  10. I am restoring my 20 inch childhood bike. If had cottered cranks and I can't find replacement cranks or bottom bracket parts. Any ideas on where I should look or who I should talk to?

    Monte

    ReplyDelete
  11. Hi Monte, are you looking for the whole crank, or just the cotters? You can buy new cotters in different sizes from Harris Cyclery:

    http://sheldonbrown.com/harris/three.html#cotters

    What other parts are you looking for? Are the original bits not reusable?

    ReplyDelete
  12. Hi Thom,

    I am looking for the entire assembly (cranks [4.5 inch], cotters, and all bottom bracket parts [outside diameter of cups 1.6 inches/40.7mm--or close enough to be machined to the correct size).

    ReplyDelete
  13. Monte, about the best thing I can recommend is eBay. You could put the word out on the Classic and Vintage section of BikeForums, too.

    ReplyDelete
  14. I'd say "whack it repeatedly"

    ReplyDelete
  15. The cottered cranks on my old Triumph infuriate me to no end. I think the flat on the spindle itself may be worn on the leftside, because it is impossible to get it to stay in place, it slips into an annoyingly just-a-little-crooked positioned compared to the drive side. This is even after replacing the old damaged pin and repositioning and retightening it several times!

    ReplyDelete
  16. Hey Thom, I realized as I continued to clean it that my '66 Phillips is missing a cotter nut. Guess I won't drive it until I replace that - are the chances good that I'll need to replace the entire cotter pin? Any advice on where to find a replacement nut besides the R nuts on eBay?

    ReplyDelete
  17. @ Deborah: take the nut from the other cotter down to the hardware store and see if they can match it. Don't forget you'll need a washer, too. If you can't find a match, then yes you'll probably be better off just getting a new cotter. Mark @ BikeSmith Design and Fabrication (just google it) has good quality cotter pins, or he used to. Check with him first if you need to replace the entire pin.

    ReplyDelete
  18. Hola Deborah, If the cotter on your 66 Phillips is anything like my 66 Puch , then you will not be able to drive out the cotter pin anyway with or without the nut they are usually in there quite well after 40 years or there abouts. If the pin does come out the crank will probably still be corroded onto the spindle and even with a puller designed to pull with a mechanical advantage it is very hard to get the cranks off. Ride on and don't sweat it. It is not a parachute. Thanks Eduard still trying to get the cranks out of the Puch and the 76 Raleigh/ not easy.

    ReplyDelete
  19. Hello again, I recently removed anything removable from my 1973 Raleigh Twenty and mounted the cotter in a bench vise with a large nut to receive the pin as it slipped out and after checking the alignment to be sure not to damage the threads applied force to the jaws of the vise and heard a clunk as the cotter pin was freed from the crank. No damage nut screwed back on. Did the same for my 70's Raleigh Record 10 speed which is now a fixed gear with same success. I removed the extra unused chainwheel and mounted chain to 52 tooth steel chainwheel and put cottered crank back on. I do like the chrome. I use an 18 tooth rear cog and have a good time going fixed. ( I did buy a proper track rear wheel with lock ring and also front light alloy rim.) bike is now about 24 pounds. Thanks Ed

    ReplyDelete