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The Infamous Dork Disc

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The Infamous Dork Disc

Old 01-15-23, 01:25 PM
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Old 01-16-23, 01:23 AM
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All I'm sayin' is if some manufacturer should make them out of CF and make them cool again
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Old 01-16-23, 07:36 AM
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Originally Posted by Hondo6
Yes, actually - though it appears to be an integral part of the largest rear sprocket and was IMO probably formed when said largest sprocket was stamped out of 2mm steel sheet vice machined. Shimano made some 5-speed Uniglide versions that were Schwinn Approved.
[ pic snipped ]

The largest rear sprocket is effectively a 28T - the four support arms for the integral "dork disk" replace 4 teeth, so it only has 24 actual teeth.

Edited to add: this is the only example I've ever seen; dunno if Shimano ever made a 6- or 7-speed version.. It's now awaiting a future build (which will be 6-speed; it takes standard Uniglide sprockets and spacers), which likely won't occur for several years in the future. The source purportedly had 2 of these, but the second turned out to be an actual Schwinn Approved 6-speed UG cassette w/o built in spoke protector on the last sprocket. I didn't really mind, as my NOS UG hub set is 6-speed.

Clever design, but likely added too much weight (2mm steel plate is fairly heavy) to catch on industry-wide. Plus, I'm also guessing either Shimano or Schwinn patented the design.
Here's the Maillard Normandy version, 32T big:



Last edited by oneclick; 01-16-23 at 07:41 AM.
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Old 01-16-23, 07:40 AM
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Originally Posted by Fredo76
[pic of corncob with normal (big) d.disk snipped]
This is the combo:


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Old 01-16-23, 08:24 AM
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This was the original question (emphasis added):

Originally Posted by Sy Reene
Has anyone ever made a cassette that has a spoke protector disc machined right onto the inside the largest cog of the cassette?
Originally Posted by oneclick
This is the combo:


Wasn't aware of that one. But it appears to be a freewheel, not a cassette, so it doesn't exactly address [MENTION=400532]Sy Reene[/MENTION] 's question above.

Originally Posted by oneclick
Here's the Maillard Normandy version, 32T big:


That may indeed be a second example, provided it came from a Maillard cassette vice a freewheel. (I believe some of their cassettes did use a 3-spline pattern, but my Maillard freewheel/cassette knowledge is rather scant.) But if so I think the Shimano example I posted may predate it, since it dates to the 5-speed Uniglide era (introduced 1979/1980).

Last edited by Hondo6; 01-16-23 at 08:31 AM.
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Old 01-16-23, 08:33 AM
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Originally Posted by Fredo76
Quite a sharp bend at the cable stop... stress riser! (Housing too long?)



Housing meets cable at zero angle... it will break somewhere else! ;-)

Last edited by sweeks; 01-16-23 at 01:20 PM.
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Old 01-16-23, 09:08 AM
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Originally Posted by Hondo6
This was the original question (emphasis added):





Wasn't aware of that one. But it appears to be a freewheel, not a cassette, so it doesn't exactly address [MENTION=400532]Sy Reene[/MENTION] 's question above.

That may indeed be a second example, provided it came from a Maillard cassette vice a freewheel. (I believe some of their cassettes did use a 3-spline pattern, but my Maillard freewheel/cassette knowledge is rather scant.) But if so I think the Shimano example I posted may predate it, since it dates to the 5-speed Uniglide era (introduced 1979/1980).
I guess these are examples, but don't see either A) why the 'dork' portion is so much larger than the largest cog, or B) why it required using some of the area that teeth would have been.

I've got one of the Prestacycle Uniblock cassettes. Something like this tech to add on an elegant dork ring might have some appeal (at least for the MTB crowd)

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Old 01-16-23, 10:08 AM
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Originally Posted by Sy Reene
I guess these are examples, but don't see either A) why the 'dork' portion is so much larger than the largest cog, or B) why it required using some of the area that teeth would have been.

I've got one of the Prestacycle Uniblock cassettes. Something like this tech to add on an elegant dork ring might have some appeal (at least for the MTB crowd)

I'd certainly think that would be possible, especially given today's CNC machining capabilities.

Whether they'd sell or not, dunno. Adding one would add weight (carbon steel's density is approx 7.84g/cm^3), as well as additional cost in terms of materials and programming/machining time.

My guess is that most buyers would perceive that the extra weight and cost isn't worth it and that it wouldn't sell well enough to be viable. But I could well be wrong.
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Old 01-16-23, 10:09 AM
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Originally Posted by CrimsonEclipse
All I'm sayin' is if some manufacturer should make them out of CF and make them cool again
I'd buy one of those.

Edit: It looks like some manufacturers have made them, but abandoned them.
https://www.wmsracing.com/instructio...ct_install.pdf
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Old 01-16-23, 10:37 AM
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Originally Posted by Hondo6
I'd certainly think that would be possible, especially given today's CNC machining capabilities.

Whether they'd sell or not, dunno. Adding one would add weight (carbon steel's density is approx 7.84g/cm^3), as well as additional cost in terms of materials and programming/machining time.

My guess is that most buyers would perceive that the extra weight and cost isn't worth it and that it wouldn't sell well enough to be viable. But I could well be wrong.
Every cassette I own is PrestaCycle/Edco monoblock.
11-32 10 speed,
a few 11-32 & 11-28 11 speeds to put on 10-speed freehub bodies that aren't 11
& 2 of the new 11-42 cassettes with the last 2 cogs cnc'd 7075 aluminum.

Their weight is plus/minus a couple of grams of SRAM RED/Dura-Ace and that's nice-n-all, but critically they wear longer than SRAM's Titanium & avoid Shimano's poor design of of individual cogs biting on aluminum freehub bodies.

That the 11-42 saves ~200grams over the same XT cassette doesn't hurt either.
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Old 01-16-23, 10:53 AM
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Originally Posted by base2
. . . . avoid Shimano's poor design of of individual cogs biting on aluminum freehub bodies.
Have to disagree here. Regarding Uniglide and Hyperglide freehubs, as far as I know Shimano's always used either steel or titanium for the freehub body. The sole exception I'm aware of was the first Dura Ace 10-speed model, which had an alloy freehub and also had taller splines for that reason. (Can't recall if contemporary Ultegra and 105 hubs were alloy or not, though some of them did use the taller splines.) If I recall correctly, Shimano changed to titanium (or maybe back to titanium; can't recall if the 7700s had titanium or steel freehubs) for DA freehubs shortly afterwards in that series (7850 and/or 7900, I think).

Shimano used steel and titanium in their freehub bodies - and went back to it after their short-lived foray into alloy with taller-splined Dura Ace freehubs - for a good reason: it was more durable, and didn't get marred by steel cogs which most everybody was using at the time. If other manufacturers chose to use a less durable material when building a Shimano-compatible freehub in order to save a bit of weight, then that was the other manufacturers' choice - not Shimano's.

I don't find it reasonable to blame Shimano for another manufacturer's decision to make a clone of Shimano's original design out of less durable materials when problems with those less durable materials surface during use.

Last edited by Hondo6; 01-16-23 at 10:57 AM.
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Old 01-16-23, 11:34 AM
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Originally Posted by Hondo6

I don't find it reasonable to blame Shimano for another manufacturer's decision to make a clone of Shimano's original design out of less durable materials when problems with those less durable materials surface during use.
Fair.
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Old 01-16-23, 03:47 PM
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Originally Posted by Hondo6
I'd certainly think that would be possible, especially given today's CNC machining capabilities.

Whether they'd sell or not, dunno. Adding one would add weight (carbon steel's density is approx 7.84g/cm^3), as well as additional cost in terms of materials and programming/machining time.

My guess is that most buyers would perceive that the extra weight and cost isn't worth it and that it wouldn't sell well enough to be viable. But I could well be wrong.
Might be interesting. The spoke protecting disc of course could be thinner gauged and doesn't need a lot of structural strength, (ie. as need to handle the chain torque). eg. machined outer aerobie type disc, coming off the largest cog. Maybe relatively little weight added?

aerobie referenced shape :-)
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Old 01-17-23, 07:16 AM
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Originally Posted by Sy Reene
Might be interesting. The spoke protecting disc of course could be thinner gauged and doesn't need a lot of structural strength, (ie. as need to handle the chain torque). eg. machined outer aerobie type disc, coming off the largest cog. Maybe relatively little weight added?

aerobie referenced shape :-)
(image omitted)
The disc could indeed be thinner than a rear sprocket - though you'd still want it to be thick enough to do its job. 10- and 11-speed rear sprockets are already down to 1.6mm thick. Would 0.5mm be enough? 0.75mm? Dunno.

The problem I'd see would be the actual fabrication if done as part of a monoblock cassette like the Presta/Edco/SRAM monoblock variants. These are machined out of a single piece of steel (some with larger rear cogs may have one or two alloy cogs attached in lieu of the largest 1 or 2 cogs being part of the steel monoblock to save weight). In the case of the Presta, that is CroMo steel.

Therein lies the problem IMO. Unless you wanted to machine it separately and attach it, it would require a larger billet. And that larger billet would require more time to program and machine. It would also generate more wear and tear on the CNC machinery, particularly the cutting heads, and would generate more waste steel millings.

Significant? Perhaps - or perhaps not. But a manufacturer would have to take that into account and price the cassette with protector disk accordingly higher. (Well, they would if they wanted to stay in business over the long term. Otherwise, maybe not. )

My guess is that an add-on - maybe one added via rivets to the largest cog - would turn out to be far more practical to manufacture. Dunno if it would sell or not.

Related, but different subject: ran across this. It seems to be a niche product aimed at the downhill biking community. It apparently replaces the largest 3 sprockets on a10-speed cassette that normally uses a spider to hold the three largest sprockets.

Not my style, but it does have a certain . . . different look. And while it appears pretty thick, since it's alloy it's not all that heavy (<50g).





Link: https://www.ebay.com/itm/25285625378

No endorsement of product intended; no experience with the vendor. Link provided for info only.

Last edited by Hondo6; 01-17-23 at 07:56 AM. Reason: Wording changes, add link, correct typo.
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Old 01-18-23, 06:33 AM
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Originally Posted by Hondo6
The disc could indeed be thinner than a rear sprocket - though you'd still want it to be thick enough to do its job. 10- and 11-speed rear sprockets are already down to 1.6mm thick. Would 0.5mm be enough? 0.75mm? Dunno.

The problem I'd see would be the actual fabrication if done as part of a monoblock cassette like the Presta/Edco/SRAM monoblock variants. These are machined out of a single piece of steel (some with larger rear cogs may have one or two alloy cogs attached in lieu of the largest 1 or 2 cogs being part of the steel monoblock to save weight). In the case of the Presta, that is CroMo steel.

Therein lies the problem IMO. Unless you wanted to machine it separately and attach it, it would require a larger billet. And that larger billet would require more time to program and machine. It would also generate more wear and tear on the CNC machinery, particularly the cutting heads, and would generate more waste steel millings.

Significant? Perhaps - or perhaps not. But a manufacturer would have to take that into account and price the cassette with protector disk accordingly higher. (Well, they would if they wanted to stay in business over the long term. Otherwise, maybe not. )

My guess is that an add-on - maybe one added via rivets to the largest cog - would turn out to be far more practical to manufacture. Dunno if it would sell or not.

Related, but different subject: ran across this. It seems to be a niche product aimed at the downhill biking community. It apparently replaces the largest 3 sprockets on a10-speed cassette that normally uses a spider to hold the three largest sprockets.

Not my style, but it does have a certain . . . different look. And while it appears pretty thick, since it's alloy it's not all that heavy (<50g).





Link: https://www.ebay.com/itm/25285625378

No endorsement of product intended; no experience with the vendor. Link provided for info only.
Seeing this and some of the other examples I am immediately thinking disk brake rather than Dork disc?
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Old 01-21-23, 06:30 PM
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Personally, the spoke protector is the second thing I remove from my own new bike, after reflectors, especially the ones in the spokes. But if you elect to keep yours, fair enough. But if it does start to spin around the hub and make a racket, please remove or replace it.
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Old 01-21-23, 07:34 PM
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Originally Posted by oldbobcat
But if you elect to keep yours, fair enough. But if it does start to spin around the hub and make a racket, please remove or replace it.
I've found that if the rear derailleur is properly adjusted, there's little risk of the chain shifting into the spokes. As for reflectors, many tires have reflective sidewalls, providing a safety factor without the thing stuck in the spokes.


22 years without a spoke protector


23 years without a spoke protector



47 years without a spoke protector!

Last edited by sweeks; 01-21-23 at 07:39 PM.
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Old 01-21-23, 08:41 PM
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Originally Posted by sweeks
I've found that if the rear derailleur is properly adjusted, there's little risk of the chain shifting into the spokes. As for reflectors, many tires have reflective sidewalls, providing a safety factor without the thing stuck in the spokes.



23 years without a spoke protector
.Thought, for a second, that you were going to compare it to the urinal protector.
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Old 01-21-23, 09:34 PM
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Originally Posted by curbtender
.Thought, for a second, that you were going to compare it to the urinal protector.

That's a 'poke protector!

Speaking of protectors, check out the home-brew crud guard for the front derailleur made from a plastic bottle and spray painted aluminum.

Last edited by sweeks; 01-21-23 at 09:57 PM.
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Old 01-27-23, 12:54 PM
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Originally Posted by Darth Lefty
beg to differ


I have put a midrive motor on my bike along with a derailleur hanger extension for the big cassette. With all the off road riding, sticks and flex at the derailleur Iíve gone through two derailleurs and hangers with the latest mishap mangling the spokes much worse than that. Iím putting spoke protecters on these wheels from now on.
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