New Departure Model D Transfer/Clutch Springs Sheering Off. Why?

[JaySeaAre]

What causes the retarder / retainer / clutch / transfer spring tab to sheer off in a New Departure Model D Coaster Hub?

I overhauled my ND Model D rear hub and found it had a broken spring. I bought a NOS spring and installed it. I tested the bike briefly and the brakes instantly failed to stop the bike. I took apart the hub and found the newly installed spring had also sheered off.

How can I fix this problem so it doesn't sheer off again? How does the transfer spring work? Does it move or rotate? Thanks!

Thanks!

 

[JaySeaAre]

This is the 1940s Schwinn DX that has the hub/spring breaking problem.

 

[kirkpatrick]

I had the same problem once, I sheared off 3 spring tabs in a row. It ended up being short a few discs, I added a few and it worked afterwards. I don’t remember how many discs their supposed to have, I’d have to look it up.

 

[kirkpatrick]

This is the 1940s Schwinn DX that has the hub/spring breaking problem.

Cool bike also.

 

[horsefarmer]

Looks like 16 total discs, 8 brass and 8 steel.

http://ratrodbikes.com/forum/index.php?threads/new-departure-model-d-rebuild.30484/

https://bikeshedva.blogspot.com/p/new-departure-model-d-coaster-brake.html

 

[The Black Monark]

https://thecabe.com/forum/threads/schwinn-service-manual-volume-1-2.96855/

disc stack should be 3/4"

 

[JaySeaAre]

Thanks, I'll look into the disk count.