If a company or individual posting to craigslist is having trouble with competitors, fake posts, harassment, etc., there are a number of ways to get things done. I'm sure that Craigslist, like every other site, makes people jump over a few hurdles before they can get in touch with a live human.
Calories Burned. On average, a 150-pound person burns 91 calories biking for 20 minutes at a leisurely pace of less than 10 miles per hour, according to the Calorie Control Council's Get Moving Calculator. The caloric burn increases to 136 calories when intensity escalates to a moderate pace, 12 to 13.9 miles per hour.
Consider Your Weight and Pace. Your weight and pace dictate how many calories you can expect to burn on an exercise bike. According to HealthStatus, a 145-pound person burns around 231 calories in 30 minutes of pedaling moderately and around 374 calories in 30 minutes of pedaling vigorously. During the two workout tempos, a 195-pound person burns about 310 and 503 calories, respectively.