Aligning PM Brakes. I don't get it!

Loads of lateral movement in those calipers

Pads out

Tighten bolts loosen enough for them to move JUST

align front end centrally

Nip up

Do the same for the rear

Snug up GENTLY

Get rid of the conical washers

I'll give that a whirl, cheers.

Also, I did wonder what benefit the washers actually provided. None it seems!

Now we need to see the rest of this shiny blue bike.

....it's grey

It's blue...

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.... aye

.... Ya right

When does the build get finished 🫣 gears are more fiddly to set up than brakes 😘

I've had to take a file to a post mount disc brake before as I couldn't set it up without rubbing. Not all makes are the same.

Also have you had your frame and fork mounts faced? The problem could be the paint isn't 100% flat.

Sounds like a facing issue.

that mount needs the conical washers though as it’s different thicknesses at the mounting points, and so the bolt heads are not square to the adaptor - conical washers sort that.

Yeah, I can't get it right. Give me IS mounts everyday.

I'll have to admit defeat and take it to the LBS next weekend.

The conical washers are also there to allow for variations in the welding. Basically you weld on the mount and then face it back but in doing that you may end up with a face that doesn't align perfectly with the bolt holes. The washers mean that won't be an issue. If you don't have enough adjustment to stop rubbing either the posts need facing or they're so off line the frame was made wrong. Occasionally you find a frame brake combo that just wont work even though both might be made as intended, but never Shimano brakes. As long as there's enough thread on the bolts there's no good reason to get rid.

I'm normally ok, but occasionally have to use a caliper alignment tool like this...

https://www.birzman.com/products_2.php?uID=2&cID=4&Key=133

Avid/Sram conical washers are there to compensate for wonky mounts, but the Shimano ones are because the adaptor’s bolt faces are not square to the frame’s disc mount face. Without them there would be a bending load on the mounting bolts.

it looks like you’ve got the rear adaptor the wrong way round which would lead to the top of the rotor rubbing the caliper itself. No re-aligning would fix that.

The arrow on the adaptor should point forwards.

it looks like you’ve got the rear adaptor the wrong way round which would lead to the top of the rotor rubbing the caliper itself. No re-aligning would fix that.

The arrow on the adaptor should point forwards.

Good spot. Blimey, I'm a ballbag.

Cheers all.

Conical washers only work above and below the caliper - but that will probably mess up your spacing. Facing the mounts will sort it -  surprised this wasn’t checked/sorted prior to leaving the factory

As above, he’s got the conical washers in the right place. Just the mount the wrong way round.

I'd get a silver Hope adapter on instead of those forged bits of crap sandwiched between frame and caliper that need conical washers and odd lengths bolts, God I hate those things, am I the only one who gets rid of them asap.

The Hope ones appear to run two sets of bolts for the same reason as Shimano using the concave/convex washers as the new caliper mounting position isn’t parallel to the frame/fork mount - the washers with one set of bolts is a neater, more efficient way of doing it I’d say. Also, forging is superior to CNCing in terms of grain structure.

The mount (black spacer part) is the wrong way round. Not using the conical washers may bend the bolts, best case, worst case it they snap.

The conical washers are in the right place. It was Avid tri-align today used them above and below. And were shite.

When you fit an adaptor that spaces out the caliper it is no longer square to the bolt (some adapters bolt onto the frame/fork then the caliper fixes onto the adapter, these are usually fine without the conical washers). The conical washers stop the shoulder of the bolt binding up on the caliper and allow easier alignment.

I agree with noeffsgiven...I much prefer the type of adapter that bolts on and then you bolt to it.
Seems more solid, and in my experience fits better on some frames where space is limited.

This type (which is basically two large washers) has given me issues more times than not.

None of that makes sense.

Despite your brake woes, that’s a very nice bike.

The Hope ones appear to run two sets of bolts for the same reason as Shimano using the concave/convex washers as the new caliper mounting position isn’t parallel to the frame/fork mount – the washers with one set of bolts is a neater, more efficient way of doing it I’d say.

I’ve used both types for various bikes and have had alignment issues with both types, so I’m not it’s a one solution fits all.

One of my bikes is running a 200mm adapter with a 203mm rotor to get the rotor to reach the top of the pads. I tried both types of 203mm and neither worked. Sometimes it’s good to have a few in the tool box!

@sillyoldman - which bit?

Obviously we are all allowed our own opinions, and IMO an adapter that bolts onto the frame or fork and then you bolt to it (negating the need for extra long bolts and conical washers) is a better engineered solution.

As far as the frame clearance thing goes, I tried putting a 180 disc on my Stooge, and because the disc mount is on the chainstay (so between the stays) the type of adapter the OP used raised the caliper up and meant the rear bolt was inaccessible. Fitting the other adapter type moved the caliper forward a bit and meant I could get to the bolt with the allen key.

Get rid of the conical washers

And you work as a bike mechanic?

I wish there was a decent facing tool for the home mechanic. Seem to be a number of good tools out there but damn they are expensive (for occasional usage). We have one frame I cannot get the alignment sorted on. Even with 0.8mm of shims under the disc it rubs, suspect that the mount is badly aligned.

I like the Galfer mounts as they don't use through bolt, but 2x bolts to attached the adaper to the bike, and then 2x bolt to attach the caliper to the mount.

https://www.rushcycles.co.uk/m87b0s454p0/Disc-Brake-Mounts/Disc-Brake-Caliper-Mounts

(Rush Cycles good source for Galfer pads and mounts etc).