A good "rule of thumb" that I've found is to use the Allen key that comes supplied with everything that I've purchased for my e-bike, and use the key this way,..
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Chances are REALLY good that you won't be able to over torque anything without your thumb and fingers saying OWE !! and your left with red detents in your thumb and fingers that last for hours.
It's not about Herculean strength.
It's all about how much it hurts to overtighten anything.
It's a very tactile approach.