# Question: New Departure Model D Rear Coaster Brake



## juanitasmith13 (Jun 13, 2016)

The driver has two narrow sets of threads on it's outer edge. The smaller diameter *is* a left hand thread for the Sprocket lock. The next inner set of threads is a larger diameter and is for the Sprocket itself... Aren't these threads, the sprocket threads, *right hand* threads?


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## juanitasmith13 (Jun 14, 2016)

I have Three drivers with sprockets; and, I have not to date been able to hold driver well enough to undo SPROCKET...
Used three kinds of penetrant; Have applied shock with a bushing and a hammer; still need to [don't want to] apply heat; but these refuse to move any direction.





I know [have removed lock ring] that the locks are LH thread... where I learned THAT, I do not recall. I also know that when you have an axle cone [for an example] you hold it in place prepared to force Counterclockwise [removal direction] as you tighten lock nut [Clockwise]... both being RH thread; and, the lock effect works. The sprocket lock [LH thread] and the sprocket are on two different diameter of thread [to enable RH thread sprocket?]; How effective is the lock, if one is RH and the other is LH? "Glenn's Complete Bicycle Manual" is quoted below... he does NOT tell us the 'lock' is LH thread; do I mis-understand his line of sight?


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## juanitasmith13 (Jun 14, 2016)

By the way... HIS manner of clamping the hub in the vise... does not stop the hub from spinning freely if you try to remove the sprocket.


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## pedal_junky (Jun 14, 2016)

Like you, I've tried without success with this method. Also tried loosening the lock nut, installing the rear wheel, pedaling fast (in the bike stand), and then applying brakes. This is supposed to loosen the sprocket, but I couldn't make it work. I broke down and bought a New Departure cog removal tool. I had a big party and removed a bucket full of drivers/sprockets from each other.


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## Gordon (Jun 14, 2016)

I believe you are correct in your assumption that the sprocket is RH thread. It has been a long time since I have had one apart, but it makes sense that the pedaling action would tighten the cog, not loosen it. They make a tool for holding the driver while removing the cog, if you search this site I think you can find photos and/or diagrams of it. Perhaps from that information you could make something that would do the same thing. Good luck.
Well, that is cool - Pedal Junky and I were typing at the same time.


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## juanitasmith13 (Jun 14, 2016)

Thank You Frank! Is this tool still available? Where did you find it?

Thank You, Gordon!


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## pedal_junky (Jun 14, 2016)

Yep, they're around. Put an ad in the wanted section. You're a good dude, I bet someone will hook you up.


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## rustjunkie (Jun 14, 2016)

If wheel/hub is out of frame:
Loosen lock ring (it has a reverse thread) just a bit.
Put hub or wheel into frame or bike with a crankset and chain on it.
Attach brake arm to brake arm strap, tension chain, tighten brake arm strap nut/bolt and axle nuts.
Apply the brake with controlled leverage.
Cog will break free, stopped by lock ring.
Remove wheel/hub from bike/frame.
remove lock ring.
remove cog.

If the wheel is already in the bike, you can loosen the lock ring a bit without removing the wheel.
This can also be done with a hub that isn't in a wheel.


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## juanitasmith13 (Jun 14, 2016)

Thank YOU, Scott! My PK DX is still in temporary 'bomber' mode; so, it was easy to remove existing rear wheel. *Besides, it has a super beautiful and comfortable, Leather Seat, from S.A. of Monrovia, CA.* It also has a 1/2" inch chain; so, I removed two tonight... the one that started this mess [from PK Phantom restoration] came off with a loud report... however: I'm not BIG enough to apply enough steady pressure, I guess. I had to jump on it a couple times. *Then*, I tried the other one with 1/2" sprocket: I had not soaked, beat, or otherwise tried too hard, on this one... I couldn't budge it... so, I removed the right pedal and stuck my favorite 4' length of 1" cheater-pipe on the crank arm. A few jumps and another loud report...DONE! Now I wonder that this design even needs a 'lock' collar! 

Scott, should this thread be moved to 'Restoration Help', to maybe more easily help others?


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## rustjunkie (Jun 15, 2016)

Glad it worked for you! Hasn't failed me yet. I've posted this a few times when I've seen the question brought up.


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## TR6SC (May 4, 2017)

When you've got a hub with no spokes and rim to help you out, nothing beats a puller.




 

 
The driver when turned by the sprocket will ride up the acme threads.  The bolt is welded to the clutch which also has acme threads. When you put the sprocket in a vise and use a pipe wrench on the clutch, the acme threads unscrew and tighten the whole shoot 'n shebang which unscrews the cog. 
Thanks rustjunkie for the parts to make this happen. The check's in the mail!

 

 

 




rustjunkie said:


> If wheel/hub is out of frame:
> Loosen lock ring (it has a reverse thread) just a bit.
> Put hub or wheel into frame or bike with a crankset and chain on it.
> Attach brake arm to brake arm strap, tension chain, tighten brake arm strap nut/bolt and axle nuts.
> ...


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## rustjunkie (May 4, 2017)

I don't get it


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## TR6SC (May 4, 2017)

The problem is how to hold the driver while unscrewing the cog. If you hold the clutch sleeve in a vise you don't damage the driver. When you unscrew the cog, the driver rides up the ramps of the acme. The bolt keeps this from happening. The aches can't unscrew and the cog comes loose.


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## rustjunkie (May 4, 2017)

What do you use to unscrew the cog?


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## TR6SC (May 4, 2017)

rustjunkie said:


> What do you use to unscrew the cog?



Use a skip tooth chain whip, or put the cog in the vise and use a pipe wrench on the clutch sleeve.


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## rustjunkie (May 4, 2017)

Ah, okay...I don't have a chain whip, or a pipe wrench, or a big vise on a bench bolted to the floor...I do, however, have a bike or two here 

Looks good tho, and I'm looking forward to checking it out


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## TR6SC (May 4, 2017)

rustjunkie said:


> Ah, okay...I don't have a chain whip, or a pipe wrench, or a big vise on a bench bolted to the floor...I do, however, have a bike or two here
> 
> Looks good tho, and I'm looking forward to checking it out



It'll go out in the mail mañana. Thanks again.


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## rustjunkie (May 4, 2017)

TR6SC said:


> It'll go out in the mail mañana. Thanks again.




Grazie, will work on a chain whip


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## Jeff54 (Jul 31, 2017)

TR6SC said:


> When you've got a hub with no spokes and rim to help you out, nothing beats a puller.
> ]





That's good info TR and close to what I'm, without just pulling it off  for part of an answer,  trying to figure out. And it seems, when it come to figuring alternative measures, ingenuity,  U da man!  I used to yank ND's apart as a kid in 60's and only recall that: I hated em. A little tricky at first, reassembling them, but easy once ya line everything up right. Yet, maybe it was because of the sprocket mount situation. At least I had a vise but not much in tools other than basic determination, there wasn't anything I couldn't rip apart and fix.

Anyways, I acquired this recently and accordingly, it ain't suposta happen. Especially after looking at diagrams it's got to be something special or else nothings holding the bearings in? Yet the wheel spins freely and very smooth.

Model D with 3 speed freewheel and 1947 Simplex 'Tour De France' on a 46, maybe 7, Schwinn DX. I hunted down plenty info about these derailleurs including an advertisement about their freewheel but the buck stops there. Nothing at all other than an offer to order different sized cogs yet, no info about Simplex's own freewheel  plus seriously nothing about adapting to any bike at all. Presumably, only made for race bikes and back then freewheel and or  cog, the mounting thread was universal?

How'd they do that, A special freewheel for ND hubs,  just plain 'Ingenuity' or ND's lock ring is that "universal" size too?

Also while I didn't think to clean before photographing it, the dust cover appears black. Potentially it's not ND's cover too.


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