"Tandem Club" said:we had a Ryno rim split last year, when we got home I used a micrometer to check thickness and found it to be 0.9mm.The new Ryno rims braking surface was 1.8mm,these where the same rims as you mention (black with circle indicators)at a guess i would say the indicators are about 0.3mmto0.4mm deep therefore leaving about 1.4mm left after the the indicators wear off
psmiffy said:what sort of factor of safety are there on rim wear indicators - the ones on my sun ryhnos disapeared about 500k ago
psmiffy said:when i have a few spare moments i will put a micrometer on them just to satisfy my own curiosity
psmiffy said:good theory but with the parrelal motion of the maguras the bevel will probably not be significant