Originally Posted by jackyharuhiko

Talking about cassette, I also talked to the bike shop yesterday about the options. My Pacific Cycles Birdy 3 is factory equipped with Shimano Sora with 11-32T 9 speed cassette, and the shop recommended me to go to 11 speed cassette but with the lowest and highest gear teeth unchanged. I wonder what is the use of going with more speed without changing the max and min gear ratio? Smoother shifting? There is also a SRAM electronic wireless system but that’s not essential to me.

I don’t know how is the original hubs, I know that the front hub has to be custom made and it’s Birdy-branded, but the back hub is a low end Shimano M475L which I saw some poor reviews online, it also stops quickly in a free spin. Anyway it’s not an issue for me since I changed the wheel set already. This hub has ceramic bearings, and it free spins for a long time, but the improvement to the ride quality is not as strong as changing the tyres and the BB/crankset. But it certainly looks good and the carbon wheels shed about 400g from the weight. Now the whole bike weighs about 11.1kg.