Originally Posted by
gpo1956
Would an average rider riding 50-75 miles a week in semi hilly terrain see a noticeable difference going from a 34 lb bike to say an 18-20 lb bike?
Assuming you're actually an average rider, you will see a difference. You will be able to accelerate faster and sustain higher speeds for a longer period of time because of the lowered mass. I'd say you will see anywhere between 10% to 15% increase in average speed if you tried only as hard as you did with your 34lb bike.
But of course, your muscles will make the maximum difference. You could ride a bike that weighs 10lb but if you just don't have the power to pedal, you're not going to see any difference...