Do the, now, standard crank arm power meters still work accurately when you are riding fixed gear, especially in hilly terrain. I'm not sure how they are actually hooked up to know just how they operate, hence why I have to ask the question. I wouldn't think you would be able to put something into the metal in the crank arm to determine the amount of force being applied to the crank arm to determine the power output. As a result I would think anything else would cause the reading to come out incorrect when going downhills or anytime you are light pedaling but the pedals are still going around.

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