Current Projects chat and miscellany

Also true, but this has always been at the cost of reducing stiffness.

Of course, there has also always been an equal amount of BS about how much frame stiffness you actually need. Even in super thin walled 753, the old fashioned 1⅛" OD down tube & seat tube with a 1" top tube yielded a frame stiff enough to have satisfactory handling in a road race geometry, although even the heavier 531 could be a bit marginal with touring loads and the correspondingly longer tubes. The problem is easily solved by adding ⅛" to all the main tube ODs, with scarcely any increase in the total amount of metal employed.

Chance of finding a 3-arm GS crankset in that condition and >170mm: negligible.
Chance that you'll notice the change: even less.

It feels odd because it's a different bike, and you've read the crank length on the back. If somebody switched the cranks on your regular bike for something 2.5mm longer or shorter without telling you, you wouldn't notice. In fact, you wouldn't even notice if they only did it to one crank.

I notice crank length plenty, road needs 170mm, mtb needs 175mm. Guess its exacerbated because I have proportionally short legs, so short cranks for spinny road work and long ones for bashing ny way up obscene gradients. I notice. My bro's hardtail is same size as mine yet do not like riding it because he has 170 cranks on it.