TL:DR Has anyone had any issues with getting the shifting working well on Shimano 12sp with a Boost converted Pro4?
I purchased an Aeris 120 mid last year, and being the owner of a 12×142 Pro4, bought the boost kit for it from Hope. Since then I have never been able to get the upshift right when coming down the block in the first 3 or 4 gears. It goes up the block fine, indexing is perfect, but when coming back down there’s always significant hesitancy in those first few (but it’s nice and quiet when it does get there).
Initially it was an all Deore 12sp setup, then I changed the shifter to an XT – still the same. Changed the rear mech to a brand new XT one yesterday and it’s still the same.
Rear hanger is straight (using a proper tool), have tried new inners and outer, complete re-set up several times, chain is on the correct way round. Chain and cassette have stayed the same (Deore) B screw is set using the guide on the back of the mech, and the chain length is correct. It’s a bit better with the clutch off, but not really.
I’m wondering if that extra offset created by the drive side boost spacer is just a stretch too far for the 12sp mech?