Viewing 13 posts - 1 through 13 (of 13 total)
  • help me setup CX expert disc brakes please
  • iainc
    Full Member

    Picked up my 2014 Croix De Fer today and had an hr fettling with it this evening.

    So its got Hayes CX expert discs and whilst I am fine with hydraulic ones I have no experience of mechanicals. I have worked out that the inner pad doesn’t seem to move, and the cable pulls the outer pad onto rotor and then onto inner pad. I’ve worked out how to move the inner pad closer to rotor and how to play with the cable tension.

    Whilst rotor is centred in caliper body ok, pulling the lever does tend to push the rotor inwards to the inner pad – can that be adjusted ? I realise its not like self centring hydraulic pistons…

    Not looked yet at how pads are removed, and could do with reccomendation for spare pads

    Many thanks

    somafunk
    Full Member

    Adjust the inner pad as close as possible to rotor but not so close that it starts to rub, place brake cable in place on the calliper actuation arm but do not tighten the lock nut, turn the cable barrel adjuster out for 3 full turns then apply the brake to the disc using your hand to operate the actuation arm and tighten the cable in place using the cable lock nut.

    This should leave you with a locked on front disc brake that stops you spinning the front wheel, now back off the barrel adjuster till the wheel turns freely without rubbing. You may have to experiment with how many initial tun outs of the barrel adjuster before you get exactly the lever feel you desire as the optimum calliper arm actuation/bite point is different from one manufacturer to another.

    I’ve not set up a pair of the Hayes CX brakes but i use the above method on Avids and Tektro and if done correctly it leaves a very solid lever feel – certainly enough to brake very hard from the hoods using just 1 or 2 fingers, i’d advise you to use a high quality brake cable & housing such as this Odyssey Linear BMX cable and housing, it does make a significant difference to the lever feel.

    13thfloormonk
    Full Member

    I think the manufacturers recommend the opposite, i.e. NOT using the cable adjuster, as this changes the position of the actuator arm and therefore the leverage the cable has on the arm.

    The Avid instructions are to clamp the calliper to the disc by winding out the inboard and outboard pads until they grab the disc between them. Then you tighten the cable to the actuator arm before winding the pads out just enough to stop rubbing on the disc.

    I think the idea is to have the actuator arm as close as possible to 90deg to the cable when the pads hit the disc.

    iainc
    Full Member

    Thanks both, will have a play tonight. A quick Google didn’t reveal a manual..

    iainc
    Full Member

    I had another look beofre going to work. Got inner pad and caliper alignment sorted such that braking isn’t really pushing rotor over, so good.

    How do I bring the outer pad in closer to the rotor though ? Only thing I seem to be able to do is move the actuator arm round by unclamping cable and putting on cable tension, which cannae be right….parrticulary given commenst above about not moving arm around and reducing angle of leverage

    There is a 5mm bolt that goes through actuator arm, but it’s nipped up, and loosening just seems to undo the whole actuator arm for removal.

    I must be missing something obvious..

    somafunk
    Full Member

    I’ve just had a look at the cx5 brake and it appears that the outer pad is directly attached to the actuator arm so you may need to do what i mentioned above regarding the turns of the adjustment barrel whilst moving the calliper as far inboard as you can so it presses against the disc then winding in the inboard pad to butt against the disc – tighten the calliper bolts and back of the inboard pad adjuster a touch along with the adjustment barrel.

    It’ll be a bit fiddly but worth persevering with till you get it spot on without any brake rub.

    iainc
    Full Member

    ok, I found this, for the CX5, which is basically the same brake :

    review

    and it says that inner pad only is adjustable, which I get. So only way i can see to adjust outer, apart from fine tuning wih the barrel adjuster, is in the cable/actuator arm setup, which can only be done by unclamping cable, pulling arm round while sighting the pad clearance, and then clamping cable tight when its as close as it can be.

    Am I missing something ?

    Thanks

    coatesy
    Free Member

    Set your actuating arm to the position you need, move the entire caliper until the outer pad clearance is correct, alter the adjuster until the inner pad clearance is correct, squeeze the lever tightly to seat the pads. Spin the wheel, check for warped rotor, straighten, adjust your clearances again to suit. Repeat until you get an acceptable result/compromise.

    iainc
    Full Member

    coatesy – excellent, thanks. one query :

    Set your actuating arm to the position you need

    how do I know where it needs to be ? I’m presuming maximun leverage ?

    coatesy
    Free Member

    Around the 90 degrees at pad contact that 13thfloormonk suggested, possibly a little more as it’ll alter as the pads wear anyway.

    iainc
    Full Member

    cheers coatesy – I’ll have a go at it this evening, much appreciated

    iainc
    Full Member

    somafunk – I’ve just reread your post from 3 hrs ago, along with the ones from 13 and coatesy – I reckon I know what to do now, many thanks to you all

    13thfloormonk
    Full Member

    Oops, I based my advice on an Avid BB7 which has an adjustable outboard pad, I guess this is what makes them ‘special’!

    Sounds like you’re sorted though.

Viewing 13 posts - 1 through 13 (of 13 total)

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