I originally tried a search on this but didn't come up with anything. I just went clipless and I'm trying to "dial in" the right positioning for the cleats. I've gotten them right under the ball of my foot. Is this right? I can't find anything that gives advice on where they should be placed. The cleats are SPD on shimano pd-m520. Is this more or less a preference thing???
Anyway I'm enjoying the clipless world now. I haven't tried any technical trails yet, but I'll get there soon.
Technically, yes - they should be right under the ball of your foot. Unless you like the feeling better with them forward or back. But you've got it right - start with them under the ball and only adjust them if you feel they are wrong/could-be-better. It's also necessary to dial in the "twist" of the cleat. You want them set so that when your foot is in its natural, neutral position on the pedal cleat is clipped in right in the middle of its lateral float.
Thanks GV27! I think that I've got them dialed in just right now. The wife and I took a 12 mile ride and they feel great! I think I'm using muscles I didn't realize I had. On the up hill portion you really feel the burn in the back of your leg.