Originally Posted by
ksryder
Depends somewhat on the bike, a Crux or a Boone or something like that will work fine on the road; I know a few guys who ride those on the weekly "worlds" ride, sometimes with fat road tires, like 32s or whatever, and it does not slow them down. Something heavier and more bikepacking-oriented like a Fargo probably won't be as fast.
My Tricross works well as a road bike, but the 50/34 crank vs. the traditional 53/39 on my road bike tends to be a limiting factor, because I can't maintain a 100+ cadence for very long.
50x11 at 90 rpm is 33mph (actually probably slightly above if you're running larger tires)
50/34 crankset should not be a limiting factor.
My race bike has a 50/34 crank. I've raced P,1,2,3 races with it, both crits, and races with mountains, and not been held back by the crank.
Only place, you'd ever be spinning more than 100 rpm would be in a sprint, or downhill. Sprinting you should be spinning a high cadence. So sprinting in a 50x11 should not limit you unless you can get over 45mph or so.
Descending, there's little return in pedaling when you get over 40mph or so. Pedal hard at the top, when you hit 40 or so, quit pedaling and tuck in. That approach will typically be faster, and more energy efficient than trying to pedal continuously on a long steep descent. So again 50x11 is going to be adequately high.
In perspective, back in the day we used to race on 52x13 which is a substantially lower gear than 50x11.
If you're limited by a 50x11, you're either doing it wrong, or are up there with Cavendish and Greipel.