Originally Posted by FIVE ONE SIX

the best thing to do would be for the OP to ride the 17lb bike with 3lbs of pennies in the water bottle, then ride the 20lb bike with an empty water bottle, and make an assumption after that test ride. that will give you the answer that your looking for, as far as if weight is really the issue...

and a 2 minute test ride isn't going to tell you anything about either bike, you need at least an hour or so, and even that isn't going to tell you what you really need to know about either of the bikes...