Help - New Departure Hub no brakes

[horsefarmer]

Took apart and re lubed ND coaster brake off my 56 Hawthorne. Dont know condition before I took it apart but now no brakes!
Here are pics of the transfer spring which I think is broken. Anyone have 1? Is it a common failure? No model stamped on hub seems original to D.P. Harris mfg bike is it model "D"? Thanks

 

[horsefarmer]

Did find a ebay seller that had NOS spring so I should be good.

 

[user 15387]

That indeed looks to me like a Model D part. This part is known as the "retarder spring" and is often the first piece to break on the Model D. There's a seller named "Bicyclebones" on Ebay who has tons of old parts, and I got my last replacement spring from him. In a pinch I have bent and re-shaped springs to fit properly, but I hate doing that. Once you have gone to the trouble of getting the hub apart, you might as well replace the spring because that is the best fix.

 

[horsefarmer]

Thanks SirMike, I think I know why the bike got parked - NO BRAKES.
Would like to know what happened to the "tail" of the retarder spring tho.
Cant find it inside the hub, maybe fell out when I took it apart.
What oil do you use on the brake pack disks? I put a little 3 in 1 oil on them now but I believe someone recommended Hypoid 80-90.
I guess the theory is the heavy oil will stay in the hub. Also my hub does not have an oilier cap so curious how often do people add oil to these hubs?

 

[user 15387]

It looks to me like the tail was sheered off. I've seen that. Replace the spring. Inspect the discs for cracks as well. Once ready to reassemble, use a medium-heavy gear oil on the discs and hub internals. Limit grease to the bearings. The grease preserves the bearings and acts as a seal to keep the oil from leaking out too much.

3-in-1 comes in a couple types. The black/red/white can should be avoided because it congeals with age. The blue/white can is ok as a bike oil in general, but I find it too light for brakes. It's similar to the old Sturmey Archer oil/sewing machine type oil (20 weight). I like heavier gear oil for brake discs in New Departure hubs.

 

[horsefarmer]

Ok, Ill be sure to clean and re- lube with gear oil. Would Lucas engine oil additive work? That stuff is extra thick!

 

[user 15387]

I've no experience with the Lucas additive. I use gear oil from the auto parts store.

 

[JaySeaAre]

That indeed looks to me like a Model D part. This part is known as the "retarder spring" and is often the first piece to break on the Model D.


What causes the retarder / retainer / clutch / transfer spring to sheer off?

I serviced my Model D rear hub and found it had a broken spring. I bought a NOS spring and installed it. When I tested the bike breifly and the breaks instantly failed. I took apart the hub and found the newly installed spring had also sheered off.

How does the transfer spring work? Does it move or rotate? Thanks!