Skiptooth Conversion

[fordmike65]

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

[NewOrleansFlyer]

Welcome to the "I-only-need-the-chain- Club"..

[dougfisk]

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.

[fordmike65]

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'!

[expjawa]

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.

[fordmike65]

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.

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

[expjawa]

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.

[Uncle Stretch]

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.

[fordmike65]

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.

[gcrank1]

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...........!!!

[expjawa]

BUT, you will load each tooth and link heavier and if you break the chain while braking a coaster...........!!!

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.

[jaysmo]

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?

[fordmike65]

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.

[Georgeediii]

I have found the Shimano rear conversion sprocket on the Bay. I have seen old crank sprockets being sold by fellow members here.

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.

[Critter1]

I have found the Shimano rear conversion sprocket on the Bay. I have seen old crank sprockets being sold by fellow members here.

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.

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.