When I convert to 20mm on pro2 (I ordered the conversion kit) will I need some kind of adaptor to make the brake calliper fit? The rotors looks miles from the fork lower when compared to a 140 fork.
While you're here, does anyone know a chain that can be fitted without specific mounts on the frame?
Cheers
You shouldn't need any adaptors for the brake if you're just going to 20mm, but obviously you will if you,re changing rotor size at the same time.
Assume you mean chain guide & not chain? Then yes, just find one that doesn't need 'ISCG mounts'
DMR for one make them, pretty sure MRP do as well.
Switching to a 20mm through hub shouldn't cause any interference with your brake caliper.
A lot of chain devices can be fitted behind the bottom bracket cups. If you're using Hollow Tech 2, i.e. external BB cups, then the backplate of the chain device simply replaces the one black spacer currently between the cup and frame. Older style BBs can still do the same thing, but I am not as sure about chainline and spacing. I've run one with an older style BB in the past and it all sort of worked, but my chainline wasn't great.
IME, the easiest devices to set up and get working using behind a BB cup are the Gamut devices (come to think of it they are the easiest to set up full stop). You can get adapters for all e13 devices as well. They look like this and usually come with the device when bought new.
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Worth checking if you're changing to 20mm to use new forks, that the forks haven't got a +20mm mount built in already, that could explain the excessive caliper to hub distance you've mentioned.