I so much enjoy reading about those unusual things you come up with Andrew! New tech is cool but I find ideas like that are more interesting to read!
When I bought my new drivetrain, instead of getting the 12 spd 11-45t cassette, I got the 12 spd Deore 11-51t all-steel cassette and a 30t front ring (thanks Race Face for making a Cinch shi-12 steel ring!) so I wouldn't have to use the 51 that much and have a better chainline on the 45t. That way the 51t would see limited use, and the steel rings would last very long anyway.
I don't know if I'd still have enough range for high-speed sections or long flat commutes between places, but going to a 28t or even 26t front would mean that I could go for the next smallest cogs on the cassette and have even more centered chainline, without having to go for a manual 2x front setup. With the wide 55mm boost chainline from Shimano, maybe we will need to choose a front ring to "select" which rear cogs will see the most use and "adjust" chainline accordingly?
Unfortunately, that still keeps the unsprung weight high and derailleur cages long, but adds clearance at the BB. The big Deore cassette's weight is still 594g of unsprung mass, but it will keep me from stopping and get my gloves dirty to switch front rings and keep my crankset setup the same : )
March 15, 2021, 8:54 a.m. - Martin
I so much enjoy reading about those unusual things you come up with Andrew! New tech is cool but I find ideas like that are more interesting to read! When I bought my new drivetrain, instead of getting the 12 spd 11-45t cassette, I got the 12 spd Deore 11-51t all-steel cassette and a 30t front ring (thanks Race Face for making a Cinch shi-12 steel ring!) so I wouldn't have to use the 51 that much and have a better chainline on the 45t. That way the 51t would see limited use, and the steel rings would last very long anyway. I don't know if I'd still have enough range for high-speed sections or long flat commutes between places, but going to a 28t or even 26t front would mean that I could go for the next smallest cogs on the cassette and have even more centered chainline, without having to go for a manual 2x front setup. With the wide 55mm boost chainline from Shimano, maybe we will need to choose a front ring to "select" which rear cogs will see the most use and "adjust" chainline accordingly? Unfortunately, that still keeps the unsprung weight high and derailleur cages long, but adds clearance at the BB. The big Deore cassette's weight is still 594g of unsprung mass, but it will keep me from stopping and get my gloves dirty to switch front rings and keep my crankset setup the same : )