I bought a cheap Wally World special Bell Cyclocomputer last week (wired). The mileage, MPH average, time, etc. all seem to be accurate. The calories burned though seem to be very different from the online "Calories Burned" calculators I use. I'm 40 years old, and weigh about 330 lbs. For a 30 mile ride averaging 12-15 mph, my cyclocomputer says I only burn about 1500 calories. I've checked on about 5 calories burned sites, and they all seem to total about 2500 calories. Anyone else notice this big of a difference?? Which one do you think is more reliable? If everything else seems to be accurate, anyone think I might need to reprogram the calories burned on the computer? Seems like a pretty big difference to me.