Originally Posted by
icemilkcoffee
Did you actually weigh the components to come up with this? I kind of doubt there is that much difference in weight. The 105 1055 and the RX100 A550 groups look really, really similar aside from finish.
They look similar, but small differences add up. The RX100's pulley cage plates are both steel. I checked a 1055 RD and one is aluminum. And the 6401 RD has two aluminum cage plates.
It's also possible that the higher-tier RDs are more hollowed-out for weight savings, but I haven't checked that closely yet.
