Is there a difference in vibration that can be felt between these lower ends? I couldn't feel a difference, but a friend says big difference. Am I numb, LOL?

 

What??? Does your friend have any explanation for why a .1875" relocation of the crank pin would result in more vibration? Is he talking about an A or B motor?

 

A motor. I told him he must have been riding a bike with a bad motor mount, or tires/wheels out of balance.

 

Or flywheels not true. That'll make a bike shake like an early-morning-alky...