Predicting rim failure
#1
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From: Beaverton, OR
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Predicting rim failure
I've got a set of Ultegra/Open Pro wheels that I've used for about 5000 miles, much of it in not so savory conditions. And now I'm wondering how much life the rims have left in them.
There was a thread on the local racing e-mail list recently about a guy who had an Open Pro split on him mid-ride. A couple of jokes were made to the effect that the Open Pro's "wear indicator" is that it explodes when it needs to be replaced. Near as I can tell, there's no intentional wear indicator mark on the rim itself. One of the LBS mechanics mentioned that you can sometimes see it coming because the rim bows out a bit at the edge.
Fast forward to today, I finally got around to inspecting my rims. I can definitely feel some curvature in the braking surface. My calipers tell me the the inside edge of the braking surface is about one millimeter narrower than the outer edge (19.3 vs. 20.5, give or take).
Should I
A) Keep riding and check it again later?
B) Take it to the LBS for a hands-on professional opinion?
C) Just replace the rim and get it over with?
Thanks.
There was a thread on the local racing e-mail list recently about a guy who had an Open Pro split on him mid-ride. A couple of jokes were made to the effect that the Open Pro's "wear indicator" is that it explodes when it needs to be replaced. Near as I can tell, there's no intentional wear indicator mark on the rim itself. One of the LBS mechanics mentioned that you can sometimes see it coming because the rim bows out a bit at the edge.
Fast forward to today, I finally got around to inspecting my rims. I can definitely feel some curvature in the braking surface. My calipers tell me the the inside edge of the braking surface is about one millimeter narrower than the outer edge (19.3 vs. 20.5, give or take).
Should I
A) Keep riding and check it again later?
B) Take it to the LBS for a hands-on professional opinion?
C) Just replace the rim and get it over with?
Thanks.
#2
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Joined: Jun 2007
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From: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
I thought the open pro rims would get a hole when it was worn out, because the wear indicator is a small divot on the inside of the rim.
anyways, I think you're nearly there. Usually road rims will have approximately 2mm of wall thickness.
anyways, I think you're nearly there. Usually road rims will have approximately 2mm of wall thickness.
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Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
#3
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Joined: Sep 2005
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From: Michigan
Bikes: Trek 730 (quad), 720 & 830, Bike Friday NWT, Brompton M36R & M6R, Dahon HAT060 & HT060, ...
Get a dental caliper. They are abundant and cheaply priced on Ebay. 5K and 'some curvature' does not sound like much wear. You need to switch the rim before the wall thickness goes down to 0.5mm.
#4
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Joined: Oct 2007
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From: West Yorkshire, United Kingdom
Option C
For rims, I go by an if in doubt replace policy, having seen someone waiting for a pick up in the middle on nowhere due to a failed / split rim, I would rather pay out a little on a new rim to prevent this happening to myself.
For rims, I go by an if in doubt replace policy, having seen someone waiting for a pick up in the middle on nowhere due to a failed / split rim, I would rather pay out a little on a new rim to prevent this happening to myself.
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