Originally Posted by
wphamilton
I don't argue with that - I take issue with what you originally wrote: "the originally lighter bike (with added weights - ed) would be faster and ride better. The lighter stock bikes tend to have more refined components that remove weight where it is less needed. "
That has little to do with mass and calculations. We have lots of old Campy, SRAM Red, Shimano 105, Ultegra and DA (most version versions over last 30 years).
One group uses stock ceramic pulleys, one bearing and one sleeves.
One group used bearings in the brake pivots, another does not.
One group...on and on.
In almost every case the correlation between price, weight and superior stuff is the same. The more expensive (within manufacture) is also lighter and also better refined.
Does better working stuff make you faster? Yes.