Originally Posted by
Paul Barnard
Appeal to him on his terms. He obviously can discern the difference between $500 audio components and $5000 components. Tell him it's like that with bicycles. There is likely a similar kind of diminishing returns as well. For example a $1000 bike will likely be twice as good as a $500 bike. The differences will be palpable. But the higher in price point you go the less the differences will be apparent.
Apparent difference is the key issue here: some but not all bike manufacturers get input from the pro riders. For instance, the head tube and fork design has changed just in the last 10 years. Those professional riders can tell the difference when racing down the Tourmalet at 50+ miles per hour while negotiating the various switchbacks. Also the grand tours with its many stages means comfort versus stiffness is considered. Continuous seattube is another example.
Not all riders will take their rides to similar conditions as those found in the Grand Tours. Not all recreational riders need to equip themselves as if they will be like the pros.