What happened to this hub locknut?
06-28-13 | 11:17 AM
#1
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From: England, currently dividing my time between university in Guildford and home just outside Reading
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What happened to this hub locknut?
While rehabbing a bike for a friend, I took apart the front hub bearings to clean and repack it and discovered that one of the locknuts looked like this on one side.
The other side looks totally normal.
I didn't use the nut, because the cutaway area extends very nearly all the way through, leaving about half a millimetre of thickness right next to the hole, so I reckon the threads would strip, but I'm curious. I'm thinking it's a manufacturing defect, as there's no way I can think of that it'd happen while the nut was on the bike, but am I missing some condition a bike sees that could cause that?
The other side looks totally normal.
I didn't use the nut, because the cutaway area extends very nearly all the way through, leaving about half a millimetre of thickness right next to the hole, so I reckon the threads would strip, but I'm curious. I'm thinking it's a manufacturing defect, as there's no way I can think of that it'd happen while the nut was on the bike, but am I missing some condition a bike sees that could cause that?
06-28-13 | 11:36 AM
#2
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you are right to not use it
you are relying on about half the threads and stripping it
is likely much more likely than a proper nut
i would guess it is just a factory defect
and the assembly line worker or robot that assembled the hub didnt notice
at first glance i thought
how could this hub have stayed together
but i suppose the bottom of the hole is about the same diameter it is supposed to be
so it will locate approximately correctly if it is held straight
and the nut will be held straight because it is tightened against a flat cone or spacer
anyhoo
i have loads of shop experience
thousands of bikes repaired
from crappy to less crappy to good
and i have never seen that before
you are relying on about half the threads and stripping it
is likely much more likely than a proper nut
i would guess it is just a factory defect
and the assembly line worker or robot that assembled the hub didnt notice
at first glance i thought
how could this hub have stayed together
but i suppose the bottom of the hole is about the same diameter it is supposed to be
so it will locate approximately correctly if it is held straight
and the nut will be held straight because it is tightened against a flat cone or spacer
anyhoo
i have loads of shop experience
thousands of bikes repaired
from crappy to less crappy to good
and i have never seen that before
06-28-13 | 01:43 PM
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06-28-13 | 02:54 PM
#6
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06-28-13 | 08:48 PM
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06-28-13 | 09:54 PM
#9
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From: San Jose, California
Bikes: 2001 Tommasini Sintesi w/ Campagnolo Daytona 10 Speed
Defect...I would say that about 1 in 300 hubs I import from Taiwan will have one of these...toss replace...get on with the business of riding.
=8-)
=8-)
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5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
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5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life
06-29-13 | 02:37 AM
#10
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From: Melbourne, Oz
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You can see it certainly happened during manufacture, because the surface treatment covers the whole part.
Looks to me like the hole is possibly punched prior to tapping, and maybe this one wasn't sitting flat during that?
Looks to me like the hole is possibly punched prior to tapping, and maybe this one wasn't sitting flat during that?
