yes, it will help lose weight in that it will build lean muscle mass, which burns more calories at your resting heart rate
HOWEVER,
if you want to lose 'inches' from your legs....bicycling will have the opposite effect AT FIRST...because you will build that muscle up, probably a little bit quicker than you actually burn the fat, depending on your metabolism.
overall, it is a fun way to lose weight, just turn the resistance up (lower gears) and try hilly areas for maximum results.
Also, consistency is KEY