In recent years, I’ve been noticing a sort of annoying grinding sound when I apply the brakes on my bicycle, something that I know hasn’t been the case all the years I’ve been riding a bike. Coming up on two years ago, I was in a bike accident courtesy of the cyclist behind me that, among other things, wrecked my rear wheel, and Dan at Freewheel built me a new one, so I ended up with one rim that is smooth (the new one) while the wheel that came with the bike has a rim that has a little groove running all the way around both sides.
I discussed this with Carlos, and he said the grinding sound comes from having dirty rims or from having grit work its way into your brake pads. He said bikes with fenders almost always have dirty rims, because moisture and dirt get between the fender and the tire and drizzle onto the rims.
I don’t doubt that is true, but just as I had almost, but not quite, embarked on a program of cleaning my rims every weekend, and loosening my brakes to inspect and clean the surfaces of the brake pads—what a misuse of time that would have been!—it became clear that the wheel that almost always makes that sound, regardless of weather, is the one with the groove in the rim.
I told Carlos that and he said it didn’t sound like the likely cause of anything to him, but on a later visit, he said I might be on to something—that he’d had another customer report the exact same thing.
I am now going to have that wheel rebuilt by ace mechanic Jason (Dan has left Freewheel) to be groove-free, but here’s the thing: These grooved rims are now required in Europe, as a safety feature—when the rim is worn down enough that the groove is no longer present, it’s time for a new wheel. I sure hope this doesn’t become the standard worldwide, because I don’t really think it’s all that groovy.