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replacing cogs on 12 speed cassette

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replacing cogs on 12 speed cassette

Old 03-04-23, 03:07 PM
  #26  
Barry2 
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Originally Posted by maddog34
Get a New Cassette.
SEVERAL badly worn teeth can be seen in the pics...a lot of the wear is directly attributable to running worn out chains, IMO..
LOL - Have you ever seen a brand new Ultegra or DA 12sp cassette.
The teeth look just like that but without the filth.

Those teeth aren't worn, that's forward motion in shifting technology!
Long gone are the days of all teeth look alike and you just have to look for the sharks fin.

All the best

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Old 03-04-23, 03:52 PM
  #27  
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Originally Posted by Barry2
LOL - Have you ever seen a brand new Ultegra or DA 12sp cassette.
The teeth look just like that but without the filth.

Those teeth aren't worn, that's forward motion in shifting technology!
Long gone are the days of all teeth look alike and you just have to look for the sharks fin.

All the best

Barry

thanks for proving my point by providing a pic of an unworn cassette. And if you wear glasses, get your prescription checked soon, ok? If not.. Buy some glasses. PS, the rider seems to use 4,5 and 6 mostly, but climbs a lot of steep hills too.

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Old 03-04-23, 04:06 PM
  #28  
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interesting discussion.

the tooth profiles on these cassettes are definitely very strange and “worn” looking out of the box.

i don’t really see the wear, but the assessment of my riding is correct. typically in 13t-16t rear and 52t up front on flats and then all the way to the 36t-34t for frequent climbs.
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Old 03-04-23, 08:19 PM
  #29  
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Originally Posted by maddog34
Get a New Cassette.
SEVERAL badly worn teeth can be seen in the pics...a lot of the wear is directly attributable to running worn out chains, IMO.
No, i won't bother pointing out each badly worn tooth.
i hope you didn't waste very much money on the two cogs that show minimal wear..... keep the new cogs as spares in case you break one... 11s are known to break on occasion..
how do "badly worn teeth" jive with the fact that it shifted (and rode) absolutely perfectly in the 13-34t cogs, but skipped in the 11 and 12 under heavy load... but now that the 11 and 12 are replaced, no skipping, perfect shifting across the board, completely silent once cleaned and lubed? the teeth profiles are certainly very ... varied, but i honestly can't see much difference between a brand new one and my 3,000 mile dirty one.

i'll wait until something is actually not working right to replace it, i think.

and agreed that chain wear snuck up on me twice.
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Old 03-18-23, 08:41 PM
  #30  
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postmortem on this :

300 miles since i replaced the two little cogs. has not skipped once. cassette works perfectly, shifts perfectly, no wierd noises from the back, so skips or mis-shifts. shop checked out the bike for an unrelated tune up a few days ago, hanger is perfectly aligned.

conclusion - it's hard to see what "wear" on these small cogs look like, but when they start skipping, they need to be replaced. the mix of strange shapes throughout the cassette make judging wear pretty difficult visually, IMO.
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