I got why they were included with Avid brakes, though a pain, they allowed for some adjustment in the caliper set up, but why did the Shimano adaptor I just bought come with a set?

Instructions here http://si.shimano.com/php/download.php?file=pdf/um/SI-0146A-000-00-ENG.pdf

..they’re not placed between the adaptor and caliper, so I cant see what purpose they serve (so I havent used them….!).

Seems like not all adaptors are sold with them:

Am I missing something obvious?!

The inline adaptors are a bit finicky, it could be an attempt to decouple the bolt alignment from the brake mount facing or to compensate for slightly bent bolts.

The one in your picture uses 4 shorter bolts, I much prefer it to the inline one.

Never used them, but looking at the instructions they give you some wriggle room if your brake mount and calliper face, where it bolts up against aren’t completely parallel.

Yeah , sorry , that pic wasnt a good example The adaptor I was working with just uses 2 bolts, slightly different length.

That’s the older design shown above, the newer version uses 2 longer bolts (not 2 to hold the adaptor and 2 for caliper). You put the washers under the heads of the bolts as the caliper is not held at 90 degrees to the bolts with this version, you need to use them or you are putting bending load onto the head of the bolt which means it could A)break, 2)come loose, iii)make it difficult to set-up.

OK….that’s interesting. But can’t see how the bend gets introduced unless the adaptor isn’t parallel in some way? How does the bolt head end up not being parallel with the outer face of the adaptor? Not disagreeing, just curious.

But can’t see how the bend gets introduced unless the adaptor isn’t parallel in some way?

The adaptor isn’t parallel in some way:

Stato has it.

I do find it amusing when people just disregard parts without knowing what they are for. By all means dont use parts (little plastic clips im looking at you, in the bin) but you at least need to know what purpose they serve before you decide you know better. Im sure no-one has died for omitting these little spacers if they lost them or something like that, but given they are supplied with the adaptor its not hard to use them.

Also worth noting, that image has the newer version bolts rather than the stupid tiny-head ones they used to supply which were easy to round. Ive pointed out more than one person who replaced their rounded long bolt with a standard (too short) bolt, risking stripping the thread out their fork (or having done so and wondered why their caliper was loose).

Who ignored them? I wouldn’t have started the thread if I wasn’t concerned.

Gotta love STW.

PS – I do find it amusing when people can’t use a 4mm Allen key…..

while we’re asking – what’s the black 2 pronged bit in the middle of that picture for?

while we’re asking – what’s the black 2 pronged bit in the middle of that picture for?

You can just disregard them! 🙂 They snap around the bolt to stop it undoing, locks into the splines around the head. I usually fit them if they are there but don’t worry about them if they aren’t. Never had or seen a bolt come loose there.

Yep if you read the PDF from the first post it shows how to use them as an alternative to lock wire. Can’t honestly say I’ve seen either used on a bike.

Yep if you read the PDF from the first post

Pfft what, read the instructions? C’mon man think what you’re saying. Thanks for the response though both, makes sense.

I’m sure I’ve got one of the above adapters with bigger (5mm) bolts that didn’t come with the Avid style washers.

This is the older one with the shallow headed bolts.

The only one ive seen that came without washers is the Avid one, but that’s for avid so it assumes your caliper is sandwiched buy the cup/cone washers anyway.