Cracked road bike rim
04-21-24, 11:25 PM
#26
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It's a confluence of bad: Aluminum has a high coefficient of thermal expansion, small diameter rim (20"), so less heat sink, and short spokes, so less elasticity. In my case, also add only using rear brake on that descent, because front rim sidewalls were more worn and I was trying to baby that. A particular small wheel bike company hypes their 20" wheels as "stronger"; Sort of. Stronger rim "hoop strength", so less likely to dent from impact. Short spokes are more rigid, but you don't want that, you want longer and more elastic, that is the driver for double-butted spokes, thinner diameter in the middle, away from bending loads on ends.
04-24-24, 01:25 PM
#27
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ADAM31: If you are going to stay with your current LBS, I strongly suggest that you educate your self about bike repair, expected component lifespans, sings of trouble, etc. In my estimation, you should not have had to ask us about that rim - it needed to be replaced, period. (Yes, it was safe enough to get you home, but not for going out on another ride. I'm glad your LBS has arranged the appropriate warranty replacement.) Expanding your bike-mechanic knowledge increases you ability to be your own "reality check" when you get advice that sounds sketchy. BF is a great place to learn such things.
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