Power cranks have been discussed at length on this site, so you might try a search. There are some vehement supporters, and there are those of us who have seen all sorts of "magic cranks" and "magic chainrings" come and go for decades, none of which ever last in the market place. It is my opinion/conclusion that these things are typically based on theories which are not supportable and have not demonstrated anything more than the ability to generate anecdotal endorsements (as opposed to documented performance improvements attributable to the device). Others will disagree strongly with this assessment.trihiker said:Hi, just wondering what people think about Power Cranks. Has anyone tried them? The company makes some bold claims. For those who've tried them, please share your experience, and any suggestions you have on how to most effectively use them.