Originally Posted by
runnergoneridin
I've watched and noted people maintaining 26 and 27 mph over lengthy rides,
I've been following some of the pro riders on the Tour de France in Strava and that's roughly their pace. For the world's top pros. Riding in a massive peloton.
Most mortals doing that pace are likely doing a TT with aero bars, or riding on a flat course, or in a paceline. Holding that speed over long distances takes a strong rider. Don't hold yourself to that, you'll get frustrated. Starting out, a 15mph average (or even less if you're in a hilly area) is probably good and build from there.
With your 50x14 gearing and 700x25c tires, 25.4mph looks to be about 91rpm cadence. That is a good average cadence for the entire ride, so if it felt really fast you could probably develop your form more to spin better. You should be able to spin up well above 100rpm although I still find my power falling off above about 110 rpm when pushing max speed.
If you are in search of top speed (I can relate) then you will want a 53x11 gear eventually. For now, just continue to develop your form and cycling fitness. When you can spin your current gearing over 30mph then I'd start worrying about a new rear cassette.