.... what are they for? The look like a giant disk brake pad, 1/2" with with a groove running through. There are in the bag with spare olives etc....
?
spacer to put between pads when transporting bikes with wheels out ?
Nope, those are red and in the calipers. These as about 1/2 inch an width an would never fit in...
To clamp the brake hose when you put the new insert in if you shorten the hoses.
Also for bleeding without pads in.
Brake pad stoppers? i.e. to stop you pulling the pads together if you accidentally pull the brake lever when the brakes are off the bike?
EDIT: Too late.
aye they are to reset the brake caliper gap when bleeding. It should be in the instructions that came with them or you can download it from the shimano site. You need to bleed without the pads in and they reset the pistons back to their maximum gap.
If they have a groove they can be clamped around the hose after cutting to help put the insert back in the end of the hose.
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IF they are the things at the bottom of this pic then they are for if you want to cut the hose they let you re-fit a new olive without crushing the hose.
Put round hose and clamp. You can then tap in the pin (centre) while holding the olive.
And if they are the other yellow thing they are the bleed block - lets you bleed brakes with pads out therefore no chance of oil on pads...
jonba / dashed, thats it exactly, Dashed your piece isn't shown on the pic but it makes sense as to the third piece I have, cheers.