Originally Posted by
gregf83
I wouldn't worry too much about torque and power until you get some more miles in your legs. Work your way up to riding consistently from 10-15 hrs/wk and your cadence and power and torque will sort itself out. At the moment you likely don't have sufficient fitness to make your legs tired. You need to build up the oxygen transport system within your body which takes time on the bike.
Cruising at low RPM feels comfortable to you now because you're not putting out much power and the force you're applying to the pedals is relatively low. As your fitness and power improves your cadence will just naturally increase.
i'm not sure as to what sort of output a typical cyclist makes. from my estimations, at cruise speeds i'm outputting about 20lb/ft @ 50-60 rpm, while the lower rpm are reducing potential power output. From a bit of messing around with calculations and such a road bike and for my cruise speed, my friend on his road bike only needs to output 70 watts, and his cadence is something like 80+. He usually averages about 18mph, but because between bike and me, he slows down for me.
Originally Posted by
hamster
The limiting factor is always cardio. My legs are strong enough to put out as much as 800 W for short periods of time, but, since my cardio system can't supply oxygen to the legs nearly as fast, if I try to go at 800 W, I get exhausted in 30 seconds. My cardio can supply oxygen for 200..220 W and I can go for an hour nonstop at that power level.
Comfortable cadence will increase with practice. Weight training (squats/leg presses) may help too.
You are probably not going to get to 300 W sustainable (cyclists often talk about max 1-hour sustainable power, or FTP). You can get to 200, you _might_ get to 250, 300 is very unlikely. You can exceed FTP for shorter periods - e.g. if your FTP is 200, you can go at 250 for 10 minutes with enough motivation.
It's much, much easier to cruise at 20 mph on a road bike than on an upright MTB.
300 watts might be a bit high. right now a 48x14 is the highest gear I have, so in order to get to 300 watts, I need to spin a minimum of something like 80 rpm, meaning I need cardio work. I would be interested in seeing how my legs deal with even higher gears. I can do 5-600lb leg presses and have done as much as 720.