Thoughts on disk-type coaster brake hubs

[mornview]

I recently picked up an old Nankai coaster brake hub off of Hxcforever (thanks again man!). I mainly bought it because of reading about it in "Glenn's New Bicycle Manual"; thanks to that book I understand that the Nankai hub, along with Hawthorne, New Departure, and others used brake disks instead of brake shoes.

I haven't heard much about coaster brakes with brake disks, so I'm curious what people think - are they superior/inferior for braking power (compared to hubs with brake shoes)? How about the longevity of the brake disks? Is there any difference in drag/resistance?

I mainly bought the hub out of curiosity, but I do plan to lace it up to something at some point. I figured hearing people's opinions on this style of hub might help me figure out what kind of project to use it on.

 

[deorman]

Not familiar with Nankai, but New Departure hubs hold up and brake well enough if you keep them oiled. They do have more drag when coasting compared to the more modern 2-cookie type.

 

[rickpaulos]

What matters more is the hub shell. The old hubs have a 1 piece shell, the new junk hubs have a pipe with 2 flanges pressed on. Those cheap hubs hubs creak and groan under adult weight. The main issue for old hubs is finding cones that aren't shot. Many are odd shaped and have non-metric threads. Yeah, there is a service for resurfacing your old cones. A stack of discs or 2/4 shoes? I've seen plenty of old ND hubs where the discs and cones are shot. Makes me wonder how much use they got over the 40-60 years. Never seen shoes worn beyond use.

rick

 

[Bicycle808]

I think a nice way of illustrating the pros and cons of the discs-vs-shoes debate is to have a look-see at the Bendix "Automatic" 2 speeds. The earliest 2 speed kickbacks were the Red-Band version; these had the disc set-up, and ran from '60-'64. From '65 to '70, they switched to the Yellow-Band, which had the shoe-type brakes. (Later, a Blue-Band was introduced, and sold concurrently with the Yellow; the difference was the Yellow (like the Red) was 1:1/underdrive, whereas the Blue was 1:1/overdrive gearing. The reasons for the change: the shoe-type was cheaper to manufacture, and theoretically required less maintenance. As time would tell, riders found that the shoes outlasted the discs.

That sums of the benefits of the shoe type, but what advantages did the Red band offer? Well, a lot of riders feel that the discs provided superior braking. Also, depending on design, discs can be made to have less drag while coasting, although this doesn't seem to be the case with the Red-Band hub. While the Red band certainly has its fans, most ppl with whom I've discussed this feel that the Yellow Band was an improvement in design.

FWIW, Nankai coaster brake hubs are well-regarded, with the primary drawback being that parts are scarce at this point. You can still buy Nankai freecoaster hubs (and they are expensive!!) but they seem to be completely out of the coaster brake game.

 

[Bicycle808]

PS- real talk about the 1piece-v-3piece hub shell, as rick paulos mentioned. TBF, I've never had serious issues with cb-e110 hub shells, despite the press-on flanges, but I've seen KTs broken at the flange. One reason I like Velosteel hubs is the quality 1-piece hub shell; the discs are good, too, b/c there's a spring to keep them from dragging while coasting, but the braking is pretty underwhelming. Seems like Velosteel has exited the US market, though. A shame.

PS- some info/schematics on the various Bendix hubs here: http://www.trfindley.com/pgbndxhbs.html Food for thought in this whole discussion

 

[mornview]

PS- real talk about the 1piece-v-3piece hub shell, as rick paulos mentioned. TBF, I've never had serious issues with cb-e110 hub shells, despite the press-on flanges, but I've seen KTs broken at the flange. One reason I like Velosteel hubs is the quality 1-piece hub shell; the discs are good, too, b/c there's a spring to keep them from dragging while coasting, but the braking is pretty underwhelming. Seems like Velosteel has exited the US market, though. A shame.

PS- some info/schematics on the various Bendix hubs here: http://www.trfindley.com/pgbndxhbs.html Food for thought in this whole discussion

Thanks for giving me reason to worry, guys ! I never really noticed that, the 3-piece construction of modern CB hub shells. I'm a pretty small guy, so I don't think I have to risk breaking anything, but still.

And thanks for the tip on Velosteel ... I'd been planning on ordering one for the longest time, and when I finally got around to it I was having the hardest time finding one. The main thing I liked that they were doing was producing hubs for all sorts of different dropout spacing ... I know eventually I'll want a 130mm CB hub; hopefully I'll be able to get my hands on one when I need it.

 

[Bicycle808]

I wouldn't sweat the flange thing too much... under JRA conditions, you'll more'n likely kill the KT hub by other means before the flanges separate from the barrel. It's usually harder use (klunkin, jumpin, hooliganism) that causes the flange(s) to fail.... I've never seen this happen to a cb-e110, but apparently it's possible. For a in-depth treatise on the current coaster hub market, check out the "tech" section of the CBC Flyer: http://www.atomiccycles.com/coaster.html

Velosteels can still be had in 32h drilling, but.... it's lookin' bad, these days, as far as gettin'm here in the States. They were making different spacings available, but they were just piling more and more spacers onto a longer axle with the same hubshell. Velosteel has a weird stepped axle, but thankfully, cb-e110 and KT hubs run on straight-up 3/8x24tpi axles. You can get a chromoly one for about $10; a worthy upgrade regardless of spacing, and at 180mm, you could space it out to 130mm with an inch of threads to spare on each end.... http://www.niagaracycle.com/categories/wheels-manufacturing-axle-34-9-5x180x24tpi-solid The problem with this, of course, is that you'll want to center the hub with the spacers, to keep the chainline right. This presents a problem where the brake's reaction arm will be far inboard. You can use brute force to bend the reaction arm outward, and then straighten the end out so the part with the hole is parallel to the stays, BUT this effectively makes the arm very short, so proper chain length and the design of the frame's dropouts becomes a crucial factor. In short, yeah, you can do it, but there are pitfalls to be aware of. (If you just try to use a long bolt and a bunch of spacers to run the clip between the arm and the stays, you're gonna brake that bolt and/or that clip, and then you got no brakes...) This was the problem with the extra-wide Velosteels that Elegant Wheels was selling. Better bet might well be to run a multi-speed coaster hub, which will have a spacing much closer to 130mm.....

 

[c.p.odom]

I can source Velosteel hubs from my customers in Germany and Austria. This is easier than dealing with Czech. I won't do this unless my mates here in the States decide not to import them anymore. I love internal disc brake hubs but they require understanding in lubrication and restoring the faces of used disc, or simply knowing when to toss damaged disc in the bin.

 

[CCR]

Out of my NOS Bendix kickback hubs I've had the red (disc) hub stops better than the yellow (shoe) hub did. Its easier to tear the shoe hubs down and repack them though which I think would of made assembly/production easier/cheaper too.

 

[mornview]

Deorman had mentioned oil; I know sometimes oil is used interchangably with grease, but sometimes you need to use more than one type of lubricant in a hub. I've always just used white lithium grease on hubs, and it's worked just fine. Is there any reason I'd need to use anything else in the Nankai hub?

As an aside, I also grabbed a Suntour coaster brake hub from Hxcforever. Mainly because I'd never worked on one before. I seem to remember Bicycle808 saying something bad about them, but I'm excited to give it a shot. I'm intrigued by their clutch spring design.

In any case, I finished overhauling the Suntour hub and now I've torn apart the Nankai hub, and it's awesome. Pretty much everything I've worked on up until this point has been more or less similar to Bendix hubs, but there are some cool design elements at play here. It really makes me wonder what other designs would've been invented had the coaster brake not fallen out of fashion. I'm REALLY eager to lace this hub up and try it out.

 

[deorman]

Oil is preferred for the discs, it allows closer contact during adhesion and easy separation upon release. Grease the bearings.

 

[Bicycle808]

I can source Velosteel hubs from my customers in Germany and Austria. This is easier than dealing with Czech. I won't do this unless my mates here in the States decide not to import them anymore. ...

Who is importing them to the USA these days? As I recall, you collab'd with Guy @ Elegant Wheels with the Velosteel w/ massive flanges riveted onto the shells, but last I checked, Guy only has 32h. The dudes at coasties.com seem to be out of all Velosteels, even 32h hubs. Some regular guys from the Netherlands have told me they'd be willing to facilitate on some Velosteels, but I don't want to trouble anyone if there's a distributor selling them straight-up.

Oil is preferred for the discs, it allows closer contact during adhesion and easy separation upon release. Grease the bearings.

+1

As an aside, I also grabbed a Suntour coaster brake hub from Hxcforever. Mainly because I'd never worked on one before. I seem to remember Bicycle808 saying something bad about them, but I'm excited to give it a shot. I'm intrigued by their clutch spring design.

I remember killing some Suntour hubs pretty quickly back when I was a kid, but the only slander I've really spread about'm comes when I repeat what Atomic Paul said about these coasters in his hub overview for the CBC: "Sun Tour: So bad, even brand new they suck. Stay away!" I will say that I overhauled a low-mileage but severely neglected example back in October; I repacked that hub with a different outlook towards coasters in general, and i recall thinking that it was a neat hub, with an interesting clutch set-up, and the quality, fit, and finish seemed really nice.... but I also felt like I could probably kill it in one good klunk'n session. Everything seemed so dainty and underbuilt....

 

[Bicycle808]

I can source Velosteel hubs from my customers in Germany and Austria. This is easier than dealing with Czech. I won't do this unless my mates here in the States decide not to import them anymore. ...

Who is importing them to the USA these days? As I recall, you collab'd with Guy @ Elegant Wheels with the Velosteel w/ massive flanges riveted onto the shells, but last I checked, Guy only has 32h. The dudes at coasties.com seem to be out of all Velosteels, even 32h hubs. Some regular guys from the Netherlands have told me they'd be willing to facilitate on some Velosteels, but I don't want to trouble anyone if there's a distributor selling them straight-up. ....

Well, whoever is selling Velosteel, tell'm to get their web-presence up; I'm trying to get some 36h Velosteel, and searches for US retailers are getting me nowhere....