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Currently fitting new set of Hope Tech 3 E4 brakes. New post mounts, brakes and discs - all Hope. I have aligned the front rotor (203mm) following hope guidance to the word, so I am happy that everything is as it should be. However when I spin the wheel the disk is moving from side to side. By that I mean when its central there is about 0.5mm clearance between the disk and the pads when I spin this it opens up to 1mm and closes down to pretty much touching on a vertical axis from one side of the pads to the other. Have tried aligning the pads but I cant prevent the disc brushing against the pads.
Hope is closed for the week or I would have called. Is this much movement likely to be in tolerance for a new disc or is it simply that the disk is slightly warped. Also wondering if this much wandering could be down to worn bearings. Any thoughts appreciated, not sure wether to just crack on or if I am wasting my time.
Probably slightly warped. From experience Hope floating rotors are a bit more prone to it than non-floating ones.
They can be straightened pretty easily with a set of smooth jaw pliers or an adjustable wrench. I've got some Knipex pliers that are perfect for it.
As long as it's not rubbing after you've straightened it a bit of wobble won't matter.
It's not unusual to have to tweak a new rotor to get drag free operation.
Worth checking that the pads are coming away square and the rubbing you hear isn't just the bottom edge of the pads.
Thanks for responses so far, problem is solved. By solved I mean I just tried fitting the rear and there isn't adequate space to fit the chunkier Hopes, they are fouling the frame, so I guess they are going back.
Know a chap who had the same issue on a yeti carbon frame. Hope hub, rotor and brake but rubbed on the frame mount.
You need to true the disc up a bit so it runs centrally. Hopes discs have always been a bit wobbly from new and most require a bit of straightening.
I've never bought a rotor that didnt need tweaking with my rotor straightening tool especially when using 4 pot brakes.
Floating rotors can foul a lot of set ups, usually when not using Hope hubs, Hope's rotor mount is more inboard than other hubs in my experience but post mounts on frames can differ too, some are too chunky, some are drilled/tapped or machined slightly wrong so the adapter gets bolted on too close to the wheel or vice versa, I've had one issue when my caliper only just centred and it was pushed inward as far as it would go, I almost needed to file the caliper's oblong bolt slots. So much for standards, all post mounts should be a certain distance from the hub centre but they're not and rotors should sit in the same place, that way you can swap wheels without needing to reset the caliper, in an ideal world in which the bike industry doesn't mug us all off.
Perfectly normal to need to straighten the disc once fitted
I fitted a set of Hope V4 vented discs today
Removed the pads, pushed the pistons back into the caliper (with the lever's master cylinder cap removed)
Fitted the discs and then fitted the calipers without the pads and centralised the caliper by eye, tightened the caliper up, fitted the pads and had a small about of rub in one particular spot
Broke out the trusty adjusty and used that to straighten the disc where it was just glancing the pads on each wheel rotation
Its now spot on with no rub, just purging the system of any small air bubbles (master cylinder cap off, lever pulled to the bars using a zip tie) lots of very tiny little air bubbles coming out of the master cylinder!