Mike,
I'll admit I'm a lycra wearing cyclist...
You start your fat a$$ on a mountain bike and swear you'll never eat yogurt and never be seen dead in lycra, just like I use to.
Then before you know it you'll be shaving your legs and tipping in thousands to fund the habit.
I used to ride a lot as a kid, I got my car and motorbike license, and I quickly forgot the joys of riding.
On the commute to work, particularly on rainy days, I recall thinking -
"those poor cyclist... what a bunch of suckers, all cold and wet 
."
Then caught in traffic one day I said bugger that, I'm riding to work tomorrow. Before I knew that 18km trip to work was quicker door to door on my bicycle.
Now, on those rainy days I look into those cars and think to myself, "poor suckers, don't know what they're missing"
Keep at it, you'll be surprised how far you can cover. I've managed as far as 210km in a day on those skin hard road bike seats. Put a pin on a map and actually see how far that is. Most people shirk at the thought of doing it in a car.
Here's a pic of my old machine:
[IMG]
[/IMG]
Weighed 6.7kg and was an absolute beauty to ride.
New machine on its way weighs in at 5.9kg and is simply put a magic carpet ride
PS: Riding a mountain bike compared to a road bike, is like competing in an Olympic running race, while wearing gumboots
Ditch the mountain bike, get a roady - Many wheels can accommodate 100kg no problems.