- My model of MX-5 is: __NA
- I’m based near: __Guildford
- I’m looking for technical help or recommendations on: __ front brake pulsing
My front brakes have been pulsing for a while so i decided to investigate today. I know it is the fromt brakes only because when i brake using handbrake only it is smooth. The pulsing slows as the speed reduces.
So i jacked the front up and had a spin of both wheels, the drivers side rotates free for half revolution and for the other half catches and is difficult to force through the pads. I tried pushing the brake pedal a few times to center and release the pads but no difference. The passenger side spins nice and free. Theres no noticeable marking on the discs and the pad wear is okay.
So i am thinking to resolve with a new set of aftermarket sport rotors and pads. The car is on 110k milea and there’s no record of discs being renewed. Brake Discs & Pads Package, Sports, MX5 Mk1 1.6 – MX5 Parts
Any thoughts or suggestions please?
Sounds good - when my front and back discs were changed by my local garage, they discovered a previous owner had updated the rears to Mk2 discs and calipers. I replaced the same and am very happy with what I’ve got - they were “standard” non-originals.
I would be checking the slide pins are free before buying anything.
If the slide pins are tight - fresh discs and pads will not fix the issue.
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Thanks for suggesting. Would the pins potentially make the pads bind on half the disc and not the other half if the disc was on spec. i.e. like new?
Yes - the slide pins allow the caliper to move and centre on the disc.
If the slide pins are stuck - there is a good chance all of the braking is being done by the inside pad only because the outside pad requires the caliper to move for it to work.
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It could also be the piston sticking in the caliper due to corrosion.
D.
If the brakes are ‘pulsing’ then (almost certainly) one or both discs are warped - possibly caused by overheating due to brakes dragging for one of the reasons suggested above (sliders, corroded piston, seized pads, etc.).
Make sure that both calipers are working smoothly and not sticking when you replace the discs.
That makes sense. Thanks.
Although components being seized is not the reason for pulsing brakes now, it could be the root cause for the rotor being warped. I dismantled and checked it last night and nothing seized.
Only the drivers side front is warped so the question now is do i need new all round or should i just do the front rotors and pads. And if i just do the front do they have to be exactly the same as rear to avoid imbalance?
FWIW: If the rears are in decent condition, I would only do the front discs & pads. If you’ve got ‘fancy’ pads in the rear, then I would match them on the front, but otherwise I wouldn’t worry.
(Other opinions are perfectly fine 
)
So, new discs and pads fitted, everything sliding nicely in all the right places. Passenger side all good like before, drivers side still appears warped when the wheel is spun. So the issue must be with the front hub being off somehow. Ill check the wheel bearing is properly torqued up first and sitting as it should, otherwise its gonna be a pair of new hubs. Ho hum.
If you have or can borrow a DTI - you could check the runout of the disc first - then the hub face.
That would confirm which is the offending part.
Apologies, actually once the wheels were back on and i went for a spin it is totally perfect! I should have properly finsihed the job before panicking … !
All good and thanks for all that shared thoughts and advice on thus thread. 
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