Knee problems are funny. Yeah, maybe lower gearing will help, but you also may want to look at bicycle fit and seat position. Try raising your seat a quarter inch and see how your knees feel. Or if your legs are already fully extended while pedaling, maybe the seat is too high. 46-18 is what I'm running right now myself. I can't imagine going lower, but I tend to mash a bit.
Before trying new gearing, move the seat around a bit and see if that helps.
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Originally Posted by
bragi 
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