A real antique
Jan. 15th, 2011 23:36![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
torquillI have been idly looking at websites on coaster brake overhaul, since I had to take one apart on the Buckeye and I had never dealt with coaster brakes before. What's baffled me is the references to brake shoes... this hub had no shoes in it. So I dug a bit deeper, and finally looked at the hub to get a make and model.
It turns out this is a New Departure Model D. I should have expected antiquity, given that I dated the bike by its chain to the mid-40s, but it simply hadn't occurred to me that the hub would be so old as to have a totally different design. Elegant, to be sure -- it doesn't wear nearly as much as the ones with shoes in them, which is doubtless why it's survived this long. I'm sure there aren't any parts to be had for love or money, which is why it's a good thing it's in such fine shape inside.
It is not, however, a typical coaster brake assembly. I think I can say with some certainty that I will never see one like this again... *sigh* I'll have to be sure to photograph it extensively before I put the hub back together.
Reassembly takes patience. Don't bother dry-fitting, as it won't spin properly without grease. Pack all bearings and grease all interior surfaces at least lightly; don't forget the inside of the hub!
Start on the brake arm side. Thread the disc support sleeve on, as far as it will go. Add the bearing cage, dust cover, and brake arm, and lock it all in place with the lock nuts on that side. From the other end, add the stack of discs (21, alternating), with a little grease between each one. Add the clutch. The transfer spring should go counterclockwise from lip to tail on the clutch. Fit the clutch sleeve over it, fitting the lip into the slot on the sleeve.
Locate the narrow side of the inside of the hub; you will insert the axle into the wide end.
Next step, quite important: line up all the tabs on the discs as precisely as possible. Hold the hub horizontal, align the tabs with the grooves on the inside of the hub, and slide it in without pulling back at all. If you do pull back, or the angle tilts too much, the clutch sleeve will come off the spring lip, and you must retrieve the whole axle and fit that back on again.
Once that's firmly inserted, start from the other end. Fit the large bearing cage into the back of the sprocket/driver, and insert that into the hub. It should spin for almost a full turn, engaging the clutch sleeve. Add the small bearing cage on the front of the driver, then thread on the cone. Tighten it until there is just barely resistance to the touch. Put on the threaded dust cover ring; it screws backward onto the front of the driver. Thread on the lock nuts.
Adjust the cone until the axle is tight but smooth, no wobble. Run the lock nuts snug against the cone and tighten them against one another. Test by spinning the axle around by the brake arm, then spinning it by the sprocket -- the brake arm should give you smooth movement with a bit of stiffness, and the sprocket should lock in one direction, then move a quarter turn or so in the other direction before engaging the clutch and locking again.
Add a little light lubricant to the peephole in the hub shell if the grease still seems a little too thick... then you're done.
It turns out this is a New Departure Model D. I should have expected antiquity, given that I dated the bike by its chain to the mid-40s, but it simply hadn't occurred to me that the hub would be so old as to have a totally different design. Elegant, to be sure -- it doesn't wear nearly as much as the ones with shoes in them, which is doubtless why it's survived this long. I'm sure there aren't any parts to be had for love or money, which is why it's a good thing it's in such fine shape inside.
It is not, however, a typical coaster brake assembly. I think I can say with some certainty that I will never see one like this again... *sigh* I'll have to be sure to photograph it extensively before I put the hub back together.
Reassembly takes patience. Don't bother dry-fitting, as it won't spin properly without grease. Pack all bearings and grease all interior surfaces at least lightly; don't forget the inside of the hub!
Start on the brake arm side. Thread the disc support sleeve on, as far as it will go. Add the bearing cage, dust cover, and brake arm, and lock it all in place with the lock nuts on that side. From the other end, add the stack of discs (21, alternating), with a little grease between each one. Add the clutch. The transfer spring should go counterclockwise from lip to tail on the clutch. Fit the clutch sleeve over it, fitting the lip into the slot on the sleeve.
Locate the narrow side of the inside of the hub; you will insert the axle into the wide end.
Next step, quite important: line up all the tabs on the discs as precisely as possible. Hold the hub horizontal, align the tabs with the grooves on the inside of the hub, and slide it in without pulling back at all. If you do pull back, or the angle tilts too much, the clutch sleeve will come off the spring lip, and you must retrieve the whole axle and fit that back on again.
Once that's firmly inserted, start from the other end. Fit the large bearing cage into the back of the sprocket/driver, and insert that into the hub. It should spin for almost a full turn, engaging the clutch sleeve. Add the small bearing cage on the front of the driver, then thread on the cone. Tighten it until there is just barely resistance to the touch. Put on the threaded dust cover ring; it screws backward onto the front of the driver. Thread on the lock nuts.
Adjust the cone until the axle is tight but smooth, no wobble. Run the lock nuts snug against the cone and tighten them against one another. Test by spinning the axle around by the brake arm, then spinning it by the sprocket -- the brake arm should give you smooth movement with a bit of stiffness, and the sprocket should lock in one direction, then move a quarter turn or so in the other direction before engaging the clutch and locking again.
Add a little light lubricant to the peephole in the hub shell if the grease still seems a little too thick... then you're done.
