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Discussion Starter · #1 ·
Ladies,

Recently installed a 19RCS Brembo brake master cylinder for both more feel and because I was sick of constantly bleeding the standard unit. Also replaced front and rear pads with Brembo street/race pads.

More power and feel from the unit but also a 'judder' under hard braking. Was probably there with the Nissan unit but less noticable.
Definitely not smooth and potentially dodgy as it interferes with the feel near lock up.

28000k and discs look o.k. and all torques to spec. No discernable play in the head bearings and the forks aren't leaking. Will swap the discs to opposite sides shortly to see if this makes any difference.

Any thoughts?

Cheers

Deano
 

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Deano,have you cleaned the disc rotor buttons with brake cleaner and made sure they are spinning and free.Its a good start.
 

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Had a judder issue during a track day. One of the caliper pistons was tight. Cleaned it all up and rotated the pads side to side. Problem solved.
 

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Discussion Starter · #5 ·
Well cleaned everything with brakeclean and swapped the discs over. Much better but still there. Revhead did you completely remove and reinstall the pistons? I checked mine out and they all seem to be moving freely and in pairs. Discs are oem and running true.

Cheers

Deano
 

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Took the calipers off and pulled the pads out. Extended the pistons out as much as I dared, cleaned them thoroughly and then reinstalled them with the pads swapped. I.e. Inner goes to outter and vice versa. If the pads are not worn evenly, this would help even things up.
Since then, I rotate the pads every service.
Might not be best practice, but I don't use the full capability of the brakes anyway.
 

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King of Bling
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.

If you still have the OEM Brembo brake discs fitted, they are prone to warping with age and hard usage.

As long as your discs aren't fully or semi floating, try doing a disc run out check with a DTI gauge.


.
 

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Discussion Starter · #8 ·
John,

Ran a dial indicator round. All good. Discs are in good nick, only 28,000k with not very savage usage.

Cheers

Deano
 

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Deano, pulsing can only come from something pushing back against the pistons. A true disc is not always a clean disc, it doesn't take much to make the lever pulse. Have you had a decent look at the disc locating rivets, are they moving freely ?
 

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King of Bling
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John,

Ran a dial indicator round. All good. Discs are in good nick, only 28,000k with not very savage usage.

Cheers

Deano
Deano

How much run out did you record ? ...

In my opinion, 28,000k is a considerable amount of use for a set of OEM discs... What's the thickness left on the discs and are they still within tolerance ?

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John;
26,600mi/42,800km '08 910R
EBC pads, not changed by me, bought it at 4,xxxmi

originally 5.5mm now 5.0mm

pads should go 40,000......

on my Aprilia RSVR Brembo pads go 8,000mi

:naughty:
 

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Discussion Starter · #12 ·
Men,

Found the problem. I have a RoadLok fitted. 'Ahha!' they cry shaking their wooden legs, why didn't he mention this in the first place? Fuck knows, didn't think it was relevant I suppose. Well it was.

Checked everything again and as I undid the caliper on the right with the Roadlok fitted I noticed one of the bolts undoing eccentrically. Checked them both in the lathe and one was bent but in no particular place. Bad manufacture. So I took the Roadlok off and rode down to score a couple of cap head bolts. Brilliant brakes again!

I think the bolt had kinked the caliper off line and this was causing the problems. Also now have doubts about the holding power re the caliper with the Roadlok installed. Thinking maybe the caliper was 'squirming' somewhat. Has been gradually getting worse.

The Roadlok is a good thing security wise, easy to use and less stuffing around than disc locks etc. but if it's going to affect the brakes it'll have to go. I'll retest it again shortly. Discs are 4.8/4.9mm thick.

Cheers

Deano
 

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King of Bling
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John;
26,600mi/42,800km '08 910R
EBC pads, not changed by me, bought it at 4,xxxmi

originally 5.5mm now 5.0mm

pads should go 40,000......

on my Aprilia RSVR Brembo pads go 8,000mi

:naughty:
Noel... You're not riding her hard enough :naughty:

:)


PS: Deano... Glad to hear you resolved the cause of the brake judder..


.
 

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on my Aprilia RSVR Brembo pads go 8,000mi

:naughty:
Noel... You're not riding her hard enough :naughty:

:)
John....I'm quiet happy with the EBCs they work, last and don't eat the discs.....

sounds like win, win, win to me

:drummer:
 

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Ebc?

Noel

I agree and I to think the EBC pads make a very good alternative to the OEM pads, especially for the Brembo Monoblock radial calipers..
John;
totally happy with the EBCs .......now I need to go to Monoblocks, I'm tired of pads worn into trapizoids because the calipers flex....with the Brembo pads.....apparently the EBCs have a higher coefficient of friction because they stay flat and the Brembos pads need more pressure....flexing the caliper

:wtf::wtf:
 

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hi Deano , there is a specif way to do your brakes it is in the manaul , this is by memory , I think you tighten one bolt up , not to tight have the other bolt in and loose then use a plastic zip tie around the brake lever pull tight so pads are sitting correct , then torque bolts up .
 

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Discussion Starter · #19 ·
Yeah done that Eddy. Aways just nip the bolts up, slacken off, apply the lever and tighten up. All good now with the new bolt. Brakes are good again.

Cheers

Deano
 

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hi Deano , there is a specif way to do your brakes it is in the manaul , this is by memory , I think you tighten one bolt up , not to tight have the other bolt in and loose then use a plastic zip tie around the brake lever pull tight so pads are sitting correct , then torque bolts up .
Yeah done that Eddy. Aways just nip the bolts up, slacken off, apply the lever and tighten up. All good now with the new bolt. Brakes are good again.

Cheers

Deano
ever see radial calipers on a car?


you might want to think about it.....

:naughty::naughty:
 
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