Originally Posted by
Bill Kapaun
Maybe that's what IRD does, without being fussy enough about spacer thickness.
IRD's using alloy spiders for the larger cogs. But it's the same fundamental problem: the spacing's not correct.
As for the OP's overall goal, it might be possible to simply switch to a compact triple (22-32-44) to effectively turn the 12-27 into the equivalent of a 14-34, provided the necessary 10-speed chain jives OK with the crank's ring spacing. But I don't know what the OP's current crank setup is, so who knows. In that scenario, the Shimano SLX or DeoreXT cranks would be worth a look.