Toe overlap is rarely an issue in crits. IMO if you’re a good rider, it’s rarely an issue in general. I have tons of toe overlap and I only have to be conscious of it below like 4mph.
I’d be more concerned about pedal strike since you’re doing fixed gear crits. I’d def go with the shortest crank I can still put power down with. So many crashes in fixed crits seem to be pedal strikes. I think 170 is on the longer side for a 54 in a fixed crit.
I also wouldn’t necessarily believe your fitter when he says “170 is optimal”. There is a lot of evidence to suggest that shorter cranks are not as suboptimal for power delivery as some people think. You just have to change your fit and gearing slightly. You’ll also have to get used to spinning at a higher rpm (same foot speed, but higher firing frequency). I can personally sprint out of the saddle upto 160+ rpm with my 165 cranks and generate my peak power somewhere around 140-150.
Last edited by smashndash; 03-16-20 at 09:59 AM.