Thursday, January 5, 2017

Rosalynn Gets A Third Brake, Plus the Most Unfortunate Tri-Coaster Adventures

And by "unfortunate," I do not mean that anything actually went wrong while I was riding, as the early Sturmey-Archer tri-coasters are known for in the wrong hands.


I had thought about how Lovely Bicycle! had added an S3C coaster to her DL-1, but I figured I had so many other bikes I rode in the rain that I could just keep the Tourist as a dry weather bike. Of course, that's not always how it works out. Despite checking the weather forecast daily out of habit, there is still a certain amount of unpredictability associated with weather and thus by this point, I have been stuck in the rain with the Tourist on more occasions than I would like. During these times, I find myself having to get off the saddle and slide to a stop with one foot on the ground. Sprinting between stoplights is part of my riding style so having at least semi-responsive brakes is a must, as funny as it sounds coming from someone who enjoys classic Raleigh bicycles. So, in the interest of possibly saving my life in times like this, I decided to add a coaster brake.


To give an extremely concise history on Sturmey-Archer tri-coasters of the 20th century, there were three main kinds: the TCW Mark I-IV, the S3C, and the AWC. As always, Sheldon Brown has some useful information on the hubs. To add to that, the AWC was introduced in 1988 and is of a newer, grease-lubricated, no-inbetween-gear design. I had both a 1988 AWC and a newer AWC II on my '72 Schwinn Speedster and they work(ed) wonderfully well. Braking isn't strong enough to lock up the rear wheel (which is a pro for me, but a con for some) but is adequate for bringing me to a stop from traffic speeds in the rain.


Despite my simple desire for a "reliable" brake, I chose the original TCW. You see, I have never been very fond of coaster brakes in the first place. Aside from the fact that hand brakes feel more natural to me and can be operated when the pedals are still turning forward, the actual major annoyance comes from not being able to rotate the pedals backward into position when starting at a red light. Here's where it gets good. Since the TCW, which is essentially an AW hub with the gears compacted to the right and a coaster brake added on the left, it has a "neutral" zone between gears 2 and 3. A properly adjusted TCW (as mine always are), just as any AW, will not have any reliability issues. Therefore, the neutral gear will only serve as an advantage to me: whenever I feel like rotating the pedals into position, all I have to do is to hold the shifter between gears 2 and 3 and boom! No more need to pick up the rear of the bike and pedal it forward. I mean, who in their right mind wants to pick up a DL-1 in the first place? Regarding concerns of braking being weaker in 3rd gear than in 1st, well, it is weaker, but that doesn't mean it's inadequate. The reason I am okay with this is that the rod brakes work just fine when they're dry and with the third brake, it only gets better. In wet weather, I usually am not traveling quite so fast anyway since I take into account visibility loss from car drivers, so having less braking power (and therefore less risk of locking up my rear tire anyway) is not such a big deal. Having said all that, it's not even that much weaker in the first place. Even with a 33% reduction in braking power, the bands will still bite.


Now, a bit about this project. Some time ago, I had purchased a 36 hole S3C hub for whatever reason. Some other time ago, I made the decision to give this bike a coaster brake. Shortly after that, I decided that a TCW would be ideal, but I would take whichever 36 hole hub that came into my hands if I couldn't find a (reportedly extremely rare) 40 hole. Then, some more time after that, I bought a 36 hole TCW III with a spare incomplete assembly because I wanted a TCW even more. I wanted to overhaul the S3C and sell it off to someone who needed it. In doing that, I found that the S3C had been cleaned out completely inside, but the driver assembly was shattered. I contacted the seller who had evidently not known about it because he resold the hub without looking inside. The person who owned it before him may have known about it since the shattered bits were nowhere to be seen. The guy who sold it to me then apologized and said he had none of the spare parts that I needed, but was willing to give me a complete hub to salvage. "Is 40 hole okay? It's the only other one I have." "Sure, I guess that works. Thanks!" I was silently thankful that I could now lace up a 40 hole S3C with my existing spokes and rim instead of having a 36 hole TCW built into a new rim (I had been planning to use Yellow Jersey's services).


So I waited. And in the mail came not a S3C, but a free 40 hole TCW hub from 1961! This was too good to be true. I waited for some spare time to begin the project. (Note: in the photo above is possibly the very last time I remember seeing my 16mm Sturmey-Archer cone spanner ... I have not been able to find it since, and the fact that it is 2 inches long doesn't help, either. It occurs to me now that I could have wrapped it up in the paper by accident and thrown it away!)


A little while before I began this project, I realized that vintage Raleigh wheels were never "laced," in that the last time each spoke crossed the 4th spoke it was supposed to cross, it was not laced behind to increase rigidity. I think they did it for ease of manufacturing, and also because the rims were so heavily made anyway that the extra strength wouldn't have mattered. When I removed the tire and rim strip, I noticed that all of the spokes were on the longer side relative to the nipples so I figured no harm would be done if I laced the rim up properly. So that I did.


After I had finished re-lacing the wheel (which, by the way, was the first time I did it without looking at the instructions and messed up), I went to install it to the bike and realized that it freewheeled backward without activating the brake. Something was wrong. Was it stuck in neutral gear inside? Nope. I tore it open and found that the entire brake screw mechanism was missing. At one point, somebody who had a coaster brake hub decided they didn't want a coaster brake and opened it up and chucked the brake screw. "Not to worry," I thought. I had one and a half spare TCW III hubs to tear into for parts!


But actually, I didn't. I laid out and opened up all of my coaster brake parts hubs and found out that I had a complete TCW III, part of an S3C, and then the aforementioned broken S3C, all of which were very similar to each other but completely different from the first generation TCW. The TCW III and S3C had been sold to me as being "TCW complete and parts" for one because what remained of the S3C was very similar to the TCW III, and also because neither the seller nor I knew at that point that the Mk III hub was very different from the Mk I. My dreams had temporarily been dashed and my bike was to sit in pieces for much longer than the one afternoon I had set aside for it.


While the TCW III and S3C had brake actuating screws attached to the planet cage, the TCW had all of these things as separate components. The TCW III and S3C both appeared to share the same left side brake arm, brake band, brake thrust plate, planet cage, bearings, and cone assemblies. The main differences were the driver and another ratchet ring which allowed the brake to be operated independently of the gears in the S3C. The first generation TCW's were completely different. That also meant that the press-fit on the left side of the hub was completely different. If you look on the exploded diagram supplied by Tony Hadland, I needed pieces K489A, K498, and K488A. These pieces, and everything to the left of that, were not interchangeable between all of the TCW generations. I then started to mix and match pieces of the different hubs in hopes that I could get them to fit together. I found that if I used the majority of the internals of my existing TCW III, I could maybe use the original TCW brake band, left side assembly, and 40 hole shell if I ground off a good chunk of the Mk III thrust plate and tried either of the brake bands.


In case that didn't work, I kept my eyes on another TCW hub (36-hole dated 1960) I had found online to scavenge. Both of these options, I came to realize, were gambles. Convincing myself that this would be the only time I would ever want a non-AWC coaster brake, I allowed myself to dip into the pile of complete and incomplete hubs and grind the old part. But that didn't work for whatever reason even though the measurements technically worked out and since my brain was already hurting, I bought the other hub online ...


And finally, after adding the necessary parts, it worked. It turns out a TCW is to remain 100% TCW, and different generations cannot be mixed together. I really do see now how much effort the engineers put forth to improve the hub before finally ditching it for the S3C. Anyway, I noticed that the bearings in the ball ring kept falling out so I swapped the dust cap out for the tighter one that came on the 1960 hub.


The small spring and the dished part pictured above went in between the brake thrust plates, concentric with the brake shoes, but somehow the brake didn't work with them in so I left them out. It works perfectly now and I don't know why. Let's just hide those extra parts for now.


I won't forget that each time I had to install, test, and remove the wheel, it was a real pain getting the chain, fender struts, rack eyelets, chain tensioners, etc. over the axle in the correct order and keep them that way while I installed the wheel with only two hands. I had initially planned to do this only once, but as you can tell with the whole "incomplete hub" issue, I had to do this quite a few times ... At least this bike didn't have a full chain case to deal with. Something I also took care of while the wheel was out was gluing a sliced inner tube along the inside the chain guard. The large 21-tooth cog brought the chain so close to the guard that even when the chain was tensioned properly, it still slapped the guard noisily and painfully over bumps. Only when the chain was way too tight did the clattering stop. Now, I don't have to worry about it.


I'm not sure whether I just got used to riding with coaster brakes since I now have two other coaster-braked bikes, but I found myself taking advantage of the inbetween gear "feature" (or folly?) surprisingly infrequently. I actually use it most often when I'm storing the bike in the corner of the living room and have to move the pedals to clear another bike. I still am happy with the performance of the TCW hub. It somehow feels more solid and tightly-made than the original AW hub in the bike, possibly attributable to the steep quality decline of Sturmey-Archer parts through the 1970s. The brake doesn't generate any perceivable drag and works much more smoothly than the rod brakes. Braking power in 3rd gear isn't so much worse than that in 1st gear that it should ever be a worry. Also, I'm glad the TCW gears and brake are all oil-lubricated, making each refill more like an oil change. No need to routinely tear down the brake to replace cooked grease. Oil makes its way out of these old hubs on its own, anyway. I went into this build wondering whether it would be worthwhile, and even after all of that trouble, I am definitely pleased with the result and happy that I went through with it.


I nearly forgot to mention the other changes to the bike. Shortly after the Old News post, right after I first finished the bike, I realized that the Brooks B67S saddle was too short for my comfort. To my surprise, the length of the "lady's" saddle actually affected me so I found a hardly-used 1973 B72 that was very dry but otherwise in great shape. I Proofided it up and crossed my fingers, and it has since been giving me a very comfortable ride without yet ripping in half.


Second, I bought a pair of Paris Packs canvas bags over half a year ago (you can tell with the summery background in the left photo) and kept them both on the bike for a while, but decided that I only needed one on this bike. The other one rotates around. I recently cut a slit in one of the aluminum hooks to position it correctly fore-and-aft on the bike, between the drop stand and where the rack slopes forward. I also had to wrap the wheel of the bottle generator with some inner tube rubber (not pictured) and slice it up for a tread pattern since the metal wheel was slipping on the tire and shredding it up.


I guess I can finally say that all of the things that have been nagging at me about this bike have been taken care of: rod brake alignment, addition of coaster brake, lining the chain guard with an inner tube, and slitting of the hooks on the bag. Something I found out is that since the rear hand brake is so much weaker than the front, the addition of the coaster brake actually makes them about equal, which is important on snow. When steel rims are dry, they actually brake better than dry alloy rims since they release less dust, and especially since I just aligned them, the front brake was actually capable of locking up the wheel on snow with surprisingly little effort.


With both of my winter bikes stuck to the rack outside, since the cables and locks got soaked with rain immediately before temperatures dropped into the teens, I have half a heart to just ride this one instead since it tracks so well and has no cables to freeze. I think I'll spare it from the salt though, since at some point I will have to refill my torch and try to melt the ice out of the locks again.


1 comment:

  1. Hi there. An interesting read about the coaster-hubs but quite hard to keep track of all the versions you had. Anyway... I don't suppose you still have that 36H S3C? (which had been 'cleaned out' prior to you buying it). Reason I ask is that I have a very nice S3C but it has a 40H shell. I need a 36H and would like to transfer the innards from my 40H to a 36H. You are welcome to have the 40H shell plus cash from my end. Thanks

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