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amey
Hi all, I recently picked up my first electronic groupset, the Shimano DI2 Dura Ace 7970 kit. I thought I'd test it before fitting it to a frame so have connected it all up. I think it's working fine but did notice a couple of things about the front mech which I'm unsure about.
Firstly when shifting through the gears with the rear mech the front mech also reacts, is this normal? For example with the front mech in the position for the larger chainring if I start with the rear mech over the smallest cog, as you shift towards the larger cogs at the rear, after four of five shifts the front mech also moves inwards a little bit, in the direction of the smaller chainring. I'm guessing this is to help avoid the chain rubbing on the inside of the front mech cage, but is that right?
Secondly again with the front mech, when I shift from the smaller chainring to the larger one I notice the mech shifts outwards as you'd expect, but then shifts back inwards slightly, is this to make sure the chain shifts and seats fully before the cage repositions to best avoid chain rub? Similarly the front mech does something similar when shifting from the larger chainring down to the smaller one, but instead shifts part of the way towards the smaller ring, but then shifts a bit further towards the smaller ring, the reason for this seems less clear.
My guess is that the mechs are working fine and all this is normal, but if anyone with experience of this or other electronic groupset a can shed any light on this matter I'd appreciate it, cheers.