This thread is timely for me. I just installed PowerGrips on my pedals this week. Got my feet into them nice and snug. Almost no wiggle room, so while these aren't clipless, I can't see how clipless could have hardly any more effect.
Have ridden on them twice, and didn't notice any difference at all in terms of effort. They did keep my feet in good position, and I don't always do that.
I'll keep them on for a while, but may be eyeing some of those nice, wide cruiser pedals I spotted the other day.
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"Too often I would hear men boast of the miles covered that day, rarely of what they had seen." Louis L'Amour
There are two types of road bikers: bikers who are faster than me, and me. Bruce Cameron - Denver Post