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Schwinn midtown bicycle, when replacing brakes I see the wheel has many grooves as shown in picture. I do not remember how it was before. Is this condition normal for the wheel rim?

Photo of the old rim and the old brakepad:
enter image description here enter image description here

Two images of the new rim:
enter image description here enter image description here

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  • 3
    I think it might be easier to interpret the first photo if the rim (or at least a section of it) was clean
    – Paul H
    Feb 1, 2021 at 23:27
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    Does a Schwinn branded rim have wear indicators when new? I can't find info either way with a quick search. Does your other wheel have the same marks?
    – Criggie
    Feb 1, 2021 at 23:47
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    looks like wear indicators to me. it's when you can't see them that you should worry
    – Paul H
    Feb 2, 2021 at 0:16
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    yeah same take. do they go all the way around the rim at a constant radius?
    – Paul H
    Feb 2, 2021 at 0:39
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    Brake pad seems very worn out. pay attention to the wear line: d3nevzfk7ii3be.cloudfront.net/igi/dKuOvxSnpsDIE2R6.medium
    – EarlGrey
    Feb 2, 2021 at 10:49

1 Answer 1

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These are wear indicators.

After years of braking, the surface of the rim will grind down to a point that these grooves will no longer be discernable. At that point, you should replace the rim.

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  • And while theyre doing it, they represent greater contact patch area for the brake blocks once the blocks have a ridge worn into them :)
    – Caius Jard
    Feb 2, 2021 at 18:41
  • The groves are far too regular to stem from wear. They were clearly machined into the rim for a purpose, either to break a film of water on the rim or as wear indicator, maybe for both purposes.
    – Carel
    Feb 3, 2021 at 18:23
  • @Carel yes. that sums up my answer
    – Paul H
    Feb 3, 2021 at 19:19

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