Skiptooth Conversion

Discussion in 'HOW TO' started by fordmike65, Feb 29, 2012.

  1. fordmike65

    fordmike65

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    Hey all. I did a bit of searching, but didn't come up with much. I'm thinking of converting my new project bike over to a skiptooth system. I have found the Shimano rear conversion sprocket on the Bay. I have seen old crank sprockets being sold by fellow members here. Now, my only missing piece is the chain. Does anyone reproduce these? Or would I have to get a good used one,which seem to demand a pretty penny? If it's gonna be too much trouble, I'll probably just stick with what came stock. Thanks in advance for any help-Mike
  2. NewOrleansFlyer

    NewOrleansFlyer

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    Welcome to the "I-only-need-the-chain- Club".. :mrgreen:
  3. dougfisk

    dougfisk

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    These chains are not being manufactured by anyone at the present time. NOS chains go for $75 to $100. Used go for $25 and up. Some used are thoroughly worn out and will not be satisfactory. Worn out = too long. Check by comparing length to a known good one, or wrap around a large sprocket and check spacing/fit to teeth.
  4. fordmike65

    fordmike65

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    Thank you for the info. Looks like I'm not the only one wanting to do this. Is it possible to use a conventional single speed chain then? Or should I just throw this idea out the window? Speaking to my Pops last night, found out he had made one of his old bikes a skiptooth when he was a kid by stealing the parts off my grandpa's bike. His bike,along with the skiptooth parts, was stolen from a friend's house. He does think my grandpa's bike may be buried somewhere in the garage. Time to start diggin'!
  5. expjawa

    expjawa

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    IIRC, skip tooth chain was 3/16" wide, rather than the 1/8" used for single-speed. So, for the same reason that can't throw narrow chain from a 10-speed, etc, on your single speed bike, you also can't throw single speed chain on a skip tooth bike...it won't fit on the sprockets.
  6. fordmike65

    fordmike65

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    Well that's that. Thank you very much for the info
  7. expjawa

    expjawa

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    Well, I suppose it isn't outside the realm of possibility to take the skip tooth sprocket and put it on a surface grinder. Taking .062" off of the face would take a while, but could be done. Obviously, any chrome plating would go with it though.
  8. Uncle Stretch

    Uncle Stretch Moderator

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    The other problem is that these chains are real old and if its not a good one ,are likely to break. It seems to happen at the worse time. I think this is where the term FACE PLANT comes from. Oh and your chain breaker won't like them either. But have fun putting some archaic piece of expensive junk on your bicycle. :lol: :lol: :lol:
  9. fordmike65

    fordmike65

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    Now,set me straight if this is a stupid idea. Is it possible to grind off every other tooth on my sprockets? Or would this cause the chain to come off more easily? Obviously I'm looking into this conversion for the vintage look aspect. But when form compromises function, I'll pass.
  10. gcrank1

    gcrank1

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    Yes, use sprockets with even number of teeth (count twice!)and std chain. It still wont look quite the same because the originals had the tooth carrying link the std pitch with a longer link in between, but it will get you closer to the look you want without great expense or replacement problems in the future.
    BUT, you will load each tooth and link heavier and if you break the chain while braking a coaster...........!!!
  11. expjawa

    expjawa

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    That's a good point - you essentially take half of the teeth out of engagement, so the load on the remaining teeth will double. The load on the chain teeth that are engaged will double.

    Either looking at the sheer strength of the teeth in a linear load or maybe as the amount of torque you can transfer from the crank to the chain, the maximum capacity is cut in half. Then factor in that the chain and teeth on a 1/8" chain are a third thinner in cross section then they are on a skip tooth set, and most likely the actual load limitation is less than half when you modify a 1/8" set to look like a skip tooth.

    Whether you actually would normally load the teeth and chain to even a half of their capacity normally is another issue. But you do, then your safety factor disappears. If you rely on the chain as a braking source (like gcrank1 noted), then you could be in trouble. I'd highly recommend having a front brake if you do this. A drum brake, even, would help and would look appropriate.
  12. jaysmo

    jaysmo

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    i have a quetion.. if you take your chain off and the master link breaks or it breaks while riding (my case).. can you just eliminate that link if you cant find a master link for a skip tooth chain?? my chain broke on my CWC last night and looks like the master link gave out and can a reqular chain tool work on it?
  13. fordmike65

    fordmike65

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    For now I will only run the coaster brake. I didn't even think of the added load on the links that are engaged. I think I will just stick with what I got. The most I'll do is install a "sweetheart" crank sprocket. The last thing I need is a link snapping when some one pulls out in front of me. I already slammed my old Honda CB into a guy blindly backing out of a driveway. I don't need any more scars.
  14. Georgeediii

    Georgeediii

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    Does anybody know if the rear conversion sprockets are easy to swap out. I am considering buying a donor bike mainly for the wheels but I want to then convert it to a skiptooth.
  15. Critter1

    Critter1

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    Yes. On most newer coaster hubs the cog is held in with a snap ring. The cog has three little notches on it that actually keeps it from rotating on its own. The new repo skip tooth cogs that are being made have the same three notches. Just take a little screwdriver or punch tool and pry up on one end of the snap ring until it pops off. Putting the snap ring back on is a little more tricky because of the tension, but it can be done with just your fingers.
  16. Ozark Flyer

    Ozark Flyer

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    Skiptooth setups reline the cool-o-meter. Go over to the auction site and buy a clean looking used diamond for $50 - $75 bucks. Drop it on and ride it hard. Worth the price. I've bought two of them with no issues. I've cleaned up rusty frozen ones from old bikes by soaking a week in both Evaporust and industrial purple cleaner from the depot and rode the heck out if them too. No biggie. Go for it!
  17. TornadoDave2

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    I know this is an older topic..... and i don't know if you are still working on your skiptooth bike.... but of you are, you may just want to try a standard 1/8 chain to see if it works. Not all skiptooths were made the same and I've run across some that will work with 1/8 chains. I've got a 1940's Columbia skiptooth that works just fine.
  18. fordmike65

    fordmike65

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    I just happened to get a deal on a sweatheart crankset & a good used chain in the classifieds. The part that was supposed to be easy,isn't. Now I can't find the rear sprocket that was sold by Skiptooth2 on eBay. I've messaged & emailed but no response. :(
  19. expjawa

    expjawa

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    The skip tooth sprocket on eBay comes and goes, and when he sells one, its usually a few days before he posts another. So, you'll just have to keep watching. I need one as well, so hopefully he hasn't run out of them... :mrgreen: If he has, I wonder how tough it would would be to spline an old sprocket to a new SA or Shimano one. It ought to be straight forward enough in a lathe to turn down the outside of a 3-tab sprocket, then open up the center of the skip tooth so that they match, then weld. We have the machining capability were I work, since we make precision gearing systems...
  20. TornadoDave2

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    if the problem is with chain fit, you can always file 1/16th of an inch in thickness off of the chainwheel's teeth, and use a standard chain and rear sprocket..... since the pitch is a compatible 2x situation.

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