Mountain Biking - Cruise Speed

What is your average speed when you commute to work on your mountain bike? How about your average 1 hour ride on pavement? I can keep a 15 mph. average on my mountain bike, is this pretty good?
However I ride a road bike until the ground is wet or covered with snow. After all the tires on the road bike just don't compare to the MTB tires. Another question, just how far is to far to ride a MTB on pavement. I have been putting in anywhere from 20 to 30 miles at a time. Is this to far to be riding a mountain bike? I mean are distances like this for road bikes? I hope someone has time to let me know if I'm nuts for riding a mountain bike at these distances!

Thanks, Scott

I don't think you're nuts, I know you're nuts. We're all nuts! Riding your mt. bike on the road doesn't make you nuts. Riding your road bike on some trails is nuts! Wait, that's cyclecross. o.k. riding a single-speed mtn bike is nuts, wait, that's been done too! I guess you are nuts!

o.k. back to your questions. Road average speed is about 17-18 mph, a little higher in a group ride. My mtn bike (with slicks)on road about 15-16, depending on how I feel. With knobbies 14-15. Average distances for mtn bike on road 15-20 miles, road bike avg weekday 20, weekends 35.

There is no "too far" on a bike, any bike. The only limit would be your own stamina and endurance. When I was about 12, I use to ride my BMX bike (20" single speed 44-15 ratio) all over town. One day my buddy and I rode for 8 hours, just to see how far we could ride. I'm guessing we rode 50-60 miles, on a BMX bike. THAT"S NUTS! If anyone tells you differently, they're nuts!

On trails avg speed doesn't exist. There is no average speed. It all depends on the terrain!

L8R G8R

Around 30km/h. Although this varies with the conditions.

My average speed is very much governed by which way the road slopes (I'm lousy up hill) - on the flat I guess on my well-laden MTB with semi-slicks I average 13-14 mph, uphill it drops to 7, downhill 27ish. Off-road I'm pretty slow.

Richard

Generally on my tourer commute at 16-17 mph, drops to 13 if cycle path because of the stop start.

I recently switched from MTB w/slicks to a full fledged road bike. On the MTB I could keep 13-15 and ride 25 miles. The second time out I rode 35 miles and 16-18 most of the time on the flats I got up to and kept 21 mph (for a little while)

The hills killed me though. I ran out of gears as I down shifted. The MTB would have been better there.

I just went out biking with a friend in the Frezzing temp (-4C)
On road going up and down it took us 9min to bike 4.5km. I didn't really look down.


Otherdays my cruise speed is around 20-35kmh