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The Infamous Dork Disc

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The Infamous Dork Disc

Old 01-09-23, 04:15 PM
  #26  
RCMoeur 
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We always called 'em "pie plates". Still use them on some bikes.
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Old 01-09-23, 04:29 PM
  #27  
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Originally Posted by grumpus
If you do bend your rear mech I think it's less likely to snag on a smooth bit of plastic than an unprotected spoke. Rear mech in spokes can have you walking home. I actually bought a plastic dork disc not long ago to fit on my hack bike because I tend to treat it careless, but I didn't check the hub flange diameter so it will be going on another bike that I've not started yet.
Then you would want a disc wheel in that case because the derailleur will likely clear the spoke protector when it bent. On my careless bike I didn't bother I just have a good derailleur and set it right and I cannot get it to overshift if I wanted to and if it does bend I am not personally confident in thin plastic that doesn't cover too much beyond the cassette in stopping it from going into the spokes.

I think yes if it were to hit smooth plastic it is less likely to snag but I don't think generally it will hit much smooth plastic unless a disc wheel or something large and even then if it was able to bend to that level I have a feeling it would have just cracked the dang thing. maybe not but those things seem to be easy to snap off.
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Old 01-09-23, 04:54 PM
  #28  
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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? Seems something like that could be the most elegant 'solution'
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.



Front View

Back View

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.

Last edited by Hondo6; 01-09-23 at 05:07 PM.
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Old 01-09-23, 05:18 PM
  #29  
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Thatís a bizarre looking cassette with the built in spoke protector. I have never seen such a thing. Iím not sure if the 4 missing teeth on the largest cog are a great idea, which results in a such a large gap between the two teeth.
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Old 01-09-23, 06:24 PM
  #30  
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Originally Posted by urbanknight
Basically, he did a crude test to see what happens when the chain falls off inside the big cog... and basically nothing really happened with or without the dork disc.
I get ya UB... It's hard to see... On my old PR-10 with it's old Campy derailleur skipping the chain off during a fast gear change can happen even when adjusted properly. Other times even with my 80's bikes when doing easy single track through high grass the derailleur can be nudged off during a shift. Of course that is quite infrequent. Lately I have been rethinking the old Dork Disk. I now have them on two of my bikes. I use them on the bikes that others may ride in that they may shift aggressively and flip that chain inward. This can happen more frequently when inexperienced riders use my non-indexed friction sifters. Of the three bikes I ride frequently one of them has a nice new clear plastic dork dish. Refusing to put a dork disk on the PR-10 my solution was to put a spacer inside the freewheel to give it a little more clearance... Ha

Of further note is the damage that comes from a slipped chain to the inner hub. If the rider keeps pedaling even a few turns the chain can do allot of damage to the spoke necks. In this picture I am trying to show that a jammed chain has caused small damage and abrasions to the most critical part of the spoke, the bend at the neck. I am now going to have to replace most of the spokes on this wheel.

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Last edited by zandoval; 01-09-23 at 06:31 PM.
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Old 01-09-23, 06:32 PM
  #31  
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Originally Posted by ARider2
That’s a bizarre looking cassette with the built in spoke protector. I have never seen such a thing. I’m not sure if the 4 missing teeth on the largest cog are a great idea, which results in a such a large gap between the two teeth.
I hadn't seen one either until I ran across that one. And yeah, it does look strange.

However, I don't see why the missing teeth would be a major problem, other than maybe making the sprocket wear out a bit faster (fewer teeth engaging per rotation). I understand 1/2" pitch chain works acceptably on skip-tooth (e.g., 1" pitch) chainrings. All one missing tooth does is create a short a skip-tooth segment in 4 places on the sprocket.

Last edited by Hondo6; 01-09-23 at 06:40 PM. Reason: Minor rewording, add missing punctuation mark.
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Old 01-09-23, 06:41 PM
  #32  
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That stamped integrated version is cool. Can't imagine it goes well with shift ramps though.

Only scraping outies is why there are eight in my photo earlier. The innies were fine
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Old 01-09-23, 06:54 PM
  #33  
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Originally Posted by dedhed
​​​​​​I set my rear wheel on fire
ha! yes!
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Old 01-09-23, 07:37 PM
  #34  
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I assert that the entire internet is wrong.

While the spoke protector is probably marginally helpful in preventing catastrophe from an overshift, it's most useful function as far as I can tell is to shield the exposed bearings in the backside of the freewheel from debris intrusion.

The rest is cultural inertia, hopes, dreams & luck.

On bikes with freewheels, I recommend the dork disc be installed for maintenance reasons more so than any disaster mitigation concerns.

It might be an unpopular sentiment but, anyone who relies on a safety device for safety usually get what they deserve.

That being said: Shiny, metal dork disks get a pass.
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Old 01-09-23, 08:44 PM
  #35  
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Originally Posted by Polaris OBark
I haven't "upgraded" to Ventura, but Safari seems to be able to do it (and I block a lot of 3rd-party garbage).
My mid 2015 MacBook is too old for anything beyond Monterey. I suspect I could poke around in some Safari setting and see what is askew, but I rarely follow video links anyway.
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Old 01-11-23, 07:27 AM
  #36  
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Back in the day: straight cut cog teeth, late shifting derailleurs that required overshift.

Now: shaped and ramped cog teeth, early shifting indexed derailleurs.
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Old 01-11-23, 08:19 AM
  #37  
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Originally Posted by ARider2
Thatís a bizarre looking cassette with the built in spoke protector. I have never seen such a thing.
I have, but not for a long time.
Originally Posted by ARider2
Iím not sure if the 4 missing teeth on the largest cog are a great idea, which results in a such a large gap between the two teeth.
The gap probably just makes it easier to shift up a gear.
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Old 01-11-23, 08:22 AM
  #38  
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Just to be wrong the guys test methodology is broken. He uses his treadmill to spin the wheels and then drops the chain with minimal torque on the cranks and, as a result, no realistic, short/long term tension in the chain. If he dropped it whilst pedaling with real world tension in the chain and his butt on the saddle he might, will, see different results.
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Old 01-11-23, 11:46 AM
  #39  
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Originally Posted by Inusuit
Style is everything.
Agree. And thus the reason to add them all to the recycling bin.

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Old 01-11-23, 12:30 PM
  #40  
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Originally Posted by base2
While the spoke protector is probably marginally helpful in preventing catastrophe from an overshift, it's most useful function as far as I can tell is to shield the exposed bearings in the backside of the freewheel from debris intrusion.
Judging by the chewed up spoke protectors I've seen they do a good job of protecting spokes on the cheap and neglected bikes that they were often fitted to. But many of those had cutouts rather than being full pie dish.

Last edited by grumpus; 01-11-23 at 12:31 PM. Reason: Messed up the quoting.
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Old 01-11-23, 03:12 PM
  #41  
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Originally Posted by rumrunn6
just don't try to burn off a plastic one
One of my favorite aphorisms that I learned back when I first became a recreational roadie is "People Who Don't Know The Correct Way To Remove A Spoke Protector Should Be Required To Ride With A Spoke Protector"
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Old 01-11-23, 05:56 PM
  #42  
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Originally Posted by Polaris OBark
Does Campy make the best one?
Seriously?
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Old 01-11-23, 05:58 PM
  #43  
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Originally Posted by oldbobcat
Seriously?
Yours is the 42nd post in the Dork Disc thread.
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Old 01-12-23, 05:16 AM
  #44  
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I typically remove them but then most of the bike I have didn't come with any. The one that did blends in so I left it on.
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Old 01-12-23, 03:13 PM
  #45  
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Originally Posted by Polaris OBark
Yours is the 42nd post in the Dork Disc thread.
Then it must be . . .(gasp!) . . . the meaning of life, the universe, and everything!

RIP, Douglas Adams. Gone far too soon.
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Old 01-12-23, 09:04 PM
  #46  
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Next thing will be bashing brake safety levers.
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Old 01-12-23, 10:18 PM
  #47  
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Just make the dork disc look like an extra big cog. Problem solved.
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Old 01-13-23, 07:34 AM
  #48  
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I think of spoke protectors (aka Dork Discs) as insurance. You don't really want if but if something does go wrong you're really glad you have it.

To me a spoke protector doesn't look any worse than a disc brake does.

Most of my bikes don't have a spoke protector.

Cheers
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Old 01-13-23, 09:30 AM
  #49  
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Originally Posted by sd5782
Next thing will be bashing brake safety levers.
ITYM brake "safety" levers - a fine example of non-cyclists deciding what's good for us.
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Old 01-13-23, 11:13 AM
  #50  
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Originally Posted by sd5782
Next thing will be bashing brake safety levers.
I'd probably bash ridiculously-frayed and bent rear derailleur cables first, but safety levers are definitely not far behind.
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