Originally Posted by
cubewheels
I used a calculator based on inseam. After I tried 150mm, I started hating 170mm.
The only advantage I see with longer cranks is enabling lower cadence when pedaling out of the saddle (OOS). Lower cadence is an advantage in OOS to avoid lactic acid build up (high cadence is not advisable for OOS unless you have incredible aerobic performance).
Workout buffs would also appreciate longer cranks as it can better emulate some leg gym workouts, better workout for more muscle groups like if you're wanting to have a bigger butt.
I tried 160mm and did not like it on my road bike even after fit adjustments. With 170mm OOS, it's true I can really feel the muscle groups I use from gym training. I do squats regularly and usually go OOS once I get close to a hill climb checkpoint allowing me to sprint to the top.