paralever bearings - how often to check'n'clean or just let them die in time?

Here are mine, dirty as hell on both sides:




I guess the dirt penetrate them very soon, so i'd say it's good to check'n'clean'n'lube them for some intervals, right? I'd say the design isn't very good on those parts, should be more sealed from dirt, coz there's just too much fun on too much gravel roads around here

Indeed, to get to those bearings is the reason why i fuced up my LH pivot bolt! Lesson learnt, on hard way. Next time i'll be more...

Cheers, Margus