Skiptooth Retrofit???

[margo]

I have a skiptooth cog on a New Departure coaster brake from a late 40's Schwinn DX that I am looking at fitting onto a newer coaster brake style wheelset. The cog is attached (assuming threaded on) to the drive screw and held on by a threaded lockring.


My question is: Is the internal threading on the drive screw (that pulls the wedge over to engage the shoes) the same size on older to newer hubs i.e. can I buy newer wheelset, pull the entire drivescrew/cog subassembly out and simply replace with the skiptooth subassembly?

Cheers,

Margo

 

[2manybikes]

I think a short answer would be no.
The drive screw on New Departure hubs is different than any other brand of hub that I have pulled apart so they I don't think you could just do a parts swap. A number of folks have had success with taking a rear cog that has an even number of teeth and grinding every other tooth off to achieve a skip tooth.

 

[margo]

A number of folks have had success with taking a rear cog that has an even number of teeth and grinding every other tooth off to achieve a skip tooth.

This was my next idea. The only issue I can see with it, is that the skiptooth cog seems thicker than a standard 1/8" cog. Will there be any issue with bad chain wear from having this extra room to move?

This bike is going to be a primary mode of transportation for my college bound sister, so I am trying to keep it as simple and maintenance free (cheap for her) as possible

 

[ifitsfreeitsforme]

i doubt the narrower cog with the ground down teeth will wear premature, or at least at a rate premature enough to notice.

 

[rms37]

As a collector I get that inch pitch is cool but don’t think the cool factor is high enough to set up a primary ride for someone who is unlikely to have a strong desire to work on the bike or want the potential added maintenance cost of running a skip-tooth drive train.

I have a couple of bikes in my collection that have been set up with ½” rear cogs with every other tooth removed to run with an inch pitch chain and sprocket. They function ok for a ride once around the block but they are noisy and feel like they are not meshing well or running smoothly.

If you lay an inch pitch sprocket on top of a half inch sprocket you will see that besides being thinner, the teeth on the half inch cog are smaller in every dimension. Even with every other tooth missing they are not the proper shape to work well with inch pitch chain.

There is no doubt that chain wear will be accelerated with a mismatched drive train but it is probably not as much a case of the system failing as that it will just become noisier and rougher running as the miles pile up. Not a problem if the bike is used infrequently but more of one if it is used daily as someone's sole means of transportation. The biggest problem though, is likely be to be finding a cheap, quick replacement chain if it does break.

It is generally easy to find a suitable ½ pitch replacement chain ring for the bike and by doing so you will probably make a ride that pedals easier, lasts longer and will be easier and much less expensive to service if the need arises. I’d save the inch pitch components for later when you sister finishes school and is ready to turn the bike into an occasion-cruiser.

 

[deorman]

Completely fake skip tooth made with even-numbered 1/2" cogs, using a regular 1/2" chain would probably work fine. I've only thought about it though, anybody done it?

 

[rms37]

In that vein, a chain on a one speed cruiser typically is wrapping more than 50% of the chain ring at any given time, so you could probably remove all but two of the teeth and it would still work if you kept the chain tension tight and had a good straight chain line.

 

[B607]

This bike is going to be a primary mode of transportation for my college bound sister, so I am trying to keep it as simple and maintenance free (cheap for her) as possible

Simple as possible means a standard chain. Save the skip tooth for your projects. Gary

 

[margo]

Thanks to all for replies.

I am thinking that a 1/2" chain is going to be what I will set up. I think I will throw the 1" drivetrain on my burrito (which needs a good pair of rusty old wheels anyway 8) ) and give my sister's ride the 1/2" off my 79 Schwinn, which I am trying to work into a hardcourt polo bike. If it works out, sweet; if not, parts is parts and they can all be rebuilt.

 

[buickmike]

I have been off for a while but I need the rrod minds now; I laced a komet hub to a nos s-2 and trued it but want to run skiptooth cog. The komet spins so smooth I wish all my ND hub bikes were equipped with them.anyone sell skipsprocket for the komet

 

[hammer mechanic]

Check out Ichi Bike:
https://ichibike.com/shop/?catid=50
The Komet cog mounting is identical.

 

[buickmike]

I hope your right h.m. I noticed. A skip cog on a modern set of24's left over from parted sk. Down in a dark basement I also observed the brake arm of the shimano. Didn't think I was lucky- I'll have to check and see. Thanks. How about a pic of that old prewar Schwinn. You took in.

 

[1oldbikelover]

I think a short answer would be no.
The drive screw on New Departure hubs is different than any other brand of hub that I have pulled apart so they I don't think you could just do a parts swap. A number of folks have had success with taking a rear cog that has an even number of teeth and grinding every other tooth off to achieve a skip tooth.

Sounds Ike a dental procedure to me

 

[buickmike]

After locating 24 shimano donor wheel with skiptooth hub have discovered cog to be half thickness of regular skip cog- furthermore it appears the teeth were ground off.so I will have to go to ichi as suggested.

 

[Tinkerbull]

It is possible using correct parts.
Picture is a vintage Topedo coaster hub thas has treaded gear mount
Velosteel hub is a replica of this one so a velo with driver from 1940 to 1959 Torpedo is a way to do it.

Picture is from this Flea-bay ad
http://www.ebay.com/itm/SINGLE-SPEE...112412?hash=item3d044c455c:g:o5kAAOSw9r1WBSsN

To pricey for me! SOB

 

[SILVERKINGPC]

I will have to go to ichi as suggested.

Thinner cogs with teeth cut off will be noisy at fist, then wear quickly as well. If you want to do it "right", buy an Ichi sprocket.

 

[buickmike]

Done; on a komet. hub.

 

[buickmike]

A parts bike project. Laced s-2 with 50's drum
Not realizing 3/8 axle won't clear prewar locker. I might be able to use porckchop on hi lo hub 40's;if tack ed spacer can be seperated.Of course all parts were bought as spares for other bikes.