annoying new disc r...
 

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[Closed] annoying new disc rub

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Just fitted brand new brakes , pads and rotor. All hope and so fully compatible even the hub and adaptor so no probs there. I fit caliper central and then centered the pads as per hope vid. Rear is perfect but front rotor has a slight wobble so although will spin when installed without rubbing as soon as I pull the brake lever once it then rubs only a slight , rub in two places but the pads are tight enough to the rotor that any play is touching the rotor. Tried giving it a bit of help to straighten out but pain in the ass floating rotor can't get it.

So will it stop once pads bed in a bit or not as I don't want to use it out side as hope won't have it back then as as I can send it back unused

It's doing my nut in


 
Posted : 08/01/2013 11:12 pm
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Ride it, the pads will wear a little probably and it'll settle. You could straighten it with an adjustable spanner, but you'll likely untrue it further.

Or if you want to persevere, then push the piston back, loosen the bolts, spin the wheel, pull the brake lever, tighten the bolts with the lever pulled and try again.


 
Posted : 08/01/2013 11:17 pm
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I've adjusted for hours today while stuck in waiting for parcel man just annoying when its all brand new and not right , bah hum bug


 
Posted : 08/01/2013 11:26 pm
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Tried giving it a bit of help to straighten out but pain in the ass floating rotor can't get it.
dont tell hope anything about you helping the rotor to straighten. 😯


 
Posted : 08/01/2013 11:31 pm
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Oh I've two that are not right mate, plus it was only with my finger as its so slight anything more would be too much, its almost like the pistons aren't retracting just quite enough


 
Posted : 08/01/2013 11:36 pm
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Have you tried slackening the rotor bolts and retightening them gently, using the "opposite bolt" method? By which I mean pinch one bolt, then the opposite until you have all six pinched; then torque them down?

Occasionally just tightening the bolts up in a "circular" way can skew the disc.

Chris


 
Posted : 09/01/2013 12:02 am
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Straightening rotors is a wee bit of a black art but there's a trick to make it easier- basically, wrangle the brake mount around so that either it or one of the bolts comes close to the rotor, then tweak it in and out til it contacts the high spot (or fails to contact the low spot, as it were). Just like using a cabletie to true a wheel. It'll have been straight when it was made but taken a knock since then, most likely.


 
Posted : 09/01/2013 12:24 am
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rickon - Member
Or if you want to persevere, then push the piston back, loosen the bolts, spin the wheel, pull the brake lever, tighten the bolts with the lever pulled and try again.

Pretty sure Hope specifically say NOT to do this in one of their videos.


 
Posted : 09/01/2013 12:59 am
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Pretty sure Hope specifically say NOT to do this in one of their videos

Why? It works well for Formula brakes.


 
Posted : 09/01/2013 1:02 am
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Not much point in moving the caliper if the fault lies with the rotor. I build bikes for a living, and it's very rare to find a straight and true rotor even on brand new bikes. Hope's floating rotors take very little effort to adjust with a spanner, it's quite easy to go too far and have it touching the other side instead. Be patient and it'll come, Hope will happily swap it if you still have a problem (as long as you haven't gone crazy on it), but it's quite possible the replacement will have a bit of run-out too.
As for Hope not recommending the pull lever/tighten bolts method, there's more to setting up a brake correctly than not having the pads touching the rotor, and a thin strip of steel like the rotor's not going to oppose the torque moving the caliper when you tighten the bolts very effectively.


 
Posted : 09/01/2013 8:34 am
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I've come off nights and looked with fresh eyes so to speak, had a ten min faff and it'll do fingers crossed bit of wearing in of pads and rotor will sort the slight ping I still have, never ever had a problem before back one
Was an old rotor too as itsohloff I just kept old one its straighter than the two new ones 😯 hope its now sorted (do you see what I did there ;))

I felt like pushing pistons out a bit loosening the hose and pushing them back in and loosing a bit of fluid but I think that will probably not solve anything as the rear looks to have the same rotor clearance as the front


 
Posted : 09/01/2013 8:50 am
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[i]Have you tried slackening the rotor bolts and retightening them gently, using the "opposite bolt" method? By which I mean pinch one bolt, then the opposite until you have all six pinched; then torque them down?[/i]

This is how you should tension rotor bolts anyway (and stem faceplate bolts too FWIW)


 
Posted : 09/01/2013 9:01 am
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As above always tightened things this way since learning to do it on cars years ago


 
Posted : 09/01/2013 11:22 am

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