Jantin uzerindeki kucuk delik gozden kaybolursa omru bitti demek. Normal kosullarda bir jantin en az 20-25000 km dayanacagini dusunuyorum. Elbette frenleme, surus sartlarina gore degisebilir. Linkte uzunca anlatilmis
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``There are two common types, a groove or a hole. A groove, like the one in the pic above, is added to the entire circumference of the rim at the centre of the braking surface. Over time this groove becomes more shallow and when it disappears, it’s time to replace the rim.
The other common wear indicator is a small hole in the sidewall, like in the photo at the top of the article. When this hole disappears, you know it’s time to replace the rim. Easy.``