Originally Posted by
lordconqueror
I have a Mavic Open Pro 32 spoke wheel that I used for commuting and cyclocross this fall into the shop the other day, and when they called to tell me it was ready, they said something to the effect of "well, we got it as true as we could. You know it was in pretty bad shape. Also, your brake surface is pretty worn, you should ask us about what rims we have in stock!"
Although it isn't prefectly true, after they worked on it it is in great shape. You can definitely feel that there is a groove worn into the brake surface, however. Should I seriously be considering another rim at this point? I would just as soon ride this rim until the braking surface is worn paper thin
You have to be pretty conservative with rim replacement, and I usually recommend replacement when a noticeable concave shape forms on the braking surface. The best-case scenario is that the tire bead that is trying to push the rim sidewall outward bends a portion of it outward, which produces a noticeably loud scraping noise as the brake pads rub on it. Worst-case, the rim fractures along the circumference, blowing the tube and leaving you stranded. On a front wheel this can cause a pretty bad crash when you get a sudden blowout (most likely to happen on a steep hill too).
I put disc brakes on my commuter mostly because of rim wear issues (I live in the rainy PAC NW). A good life-span for road rims here when commuting in stop and go traffic can be 2-3 years.