I normally change mine about every 3 years, I don't think they like sitting so close to a hot cylinder head. Not ultra expensive, easy to fit, and the worth it just for the orgasmic pleasure of operating the clutch with a brand new smoothly operating cable. I've got some of the old ones still hanging up with oil seeping through them, but y'know I think part of the New Year's clear out is going to include them! Happy New Year everybody, and stay upright. Michael.