Front Brake vibes...

Discussion in 'Maintenance' started by Mr OCD, May 18, 2017.

  1. Mr OCD

    Mr OCD Well-Known Member

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    You know what ... if buying new discs resolves the issue I don't care what they cost! :D I'm just sick of the vibration now!

    Does anyone have a spare set kicking about I can beg / borrow?
     
  2. Dave dunlop

    Dave dunlop Elite Member

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    It's not just about the thickness it's more to do with the heat build up causing surface hardening in places, that's why you see heat spots on discs, it actually changes the metal properties leaving you with hard areas that can cause the type of situation your describing, leading too oscillation and other braking issues! So what are they running out by?? you also need the Specs of runout from Brembo themselves, as the specs might be different from the OE values. I could tell you a story about a set of discs that were sold on here not too long ago! The guy ran with them for a while and then sold them on eBay, within days of the guy fitting them there was obviously an underlying issue and the guy had to have them back! Unless you know the history of parts like that I would leave well alone! Sorry just my option.... If you were closer I would loan you mine just to eliminate the situation
     
  3. Dave dunlop

    Dave dunlop Elite Member

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    You can always just buy the new discs and bobbins and keep the central rota and rebuild them! job done

    Speak to Ian at Mode performance he will sort you out:D
     
  4. Mr OCD

    Mr OCD Well-Known Member

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    Not checked them yet. Wont be able to do so till later on tonight. :) I'll look for tolerance for Brembo ORO in the meantime.

    To be fair to Daz they were fine when fitted and he is well known on here. Hence I had no doubts at all from buying from him.

    @Frankblue has kindly offered me the loan of his brand new pair of OE brake discs to try. So once I have checked the run out I will install and see if the vibration disappears. I might as well fit the brand new SKF bearings that have arrived today at the same time.

    I'm going to be sick of stripping the front end down shortly... :D
     
  5. Mr OCD

    Mr OCD Well-Known Member

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    Not checked them yet. Wont be able to do so till later on tonight. :) I'll look for tolerance for Brembo ORO in the meantime.


    To be fair to Daz @Daznorthwest they were fine when fitted and he is well known on here. Hence I had no doubts at all from buying from him.

    @Frankblue has kindly offered me the loan of his brand new pair of OE brake discs to try. So once I have checked the run out I will install and see if the vibration disappears. I might as well fit the brand new SKF bearings that have arrived today at the same time.

    I'm going to be sick of stripping the front end down shortly... :D
     
  6. Mr OCD

    Mr OCD Well-Known Member

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    For the cost of brand new replacements from Italy I can't be arsed with the aggro. :D

    However, confirming first before spending £300 makes me happy!
     
  7. Dave dunlop

    Dave dunlop Elite Member

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    I'm not implying the ones you had from him are beyond specs, just saying you need to know the history! And I personally know of a recent similar issue that's all.
     
  8. Mr OCD

    Mr OCD Well-Known Member

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    Indeed. I've had issues in the past buying used discs so I understand what your saying.

    So who is betting a soapy fiver it is the brake discs?
     
  9. Dave dunlop

    Dave dunlop Elite Member

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    As originally posted.....I would up the bet to a tenner!! That's just because I'm a tight arse! But convinced that's your issue.... simple...

    I wouldn't go out and buy new callipers and put second hand pads in, or vice a verse personally unless your 100% sure of its history and uses.... period
     
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  10. Mr OCD

    Mr OCD Well-Known Member

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    DTI ... can only do edge of disc due to holes ...

    0.1mm max each side ... :/

    Quite surprised by that ... also noticed from tyre is squaring off which won't be helping ...
     
  11. Dave dunlop

    Dave dunlop Elite Member

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    Thought you had eliminated all other options!!! you keep coming back with this is a bit worn that's a bit worn..... mate sort yourself and stop chasing your tail around.... if you can't get the basics right then your going to replacing your forks next!! If the tyre is squared off then its last legs!! surely that would have been a priority over all the rest of the stuff you fitted..... I really can't advise you any more mate as it's like banging your head against the wall.... all this stuff is a process of elimination and your not even getting the basics righto_O
     
    #91 Dave dunlop, Jul 7, 2017
    Last edited: Jul 7, 2017
  12. thefirebloke

    thefirebloke Elite Member

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    It makes for a great read though! :D
     
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  13. Mr OCD

    Mr OCD Well-Known Member

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    Fair point and noted.

    I'm being overly critical about everything. There is at least another couple thousand miles left in the tyre ... you can only feel with your hand it's starting to go out of shape. It's not a 50p! But thought would mention it!

    I'm changing the discs next and then the calipers.
     
  14. Dave dunlop

    Dave dunlop Elite Member

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    You need to ask yourself some really basic questions

    When did the vibration start?

    Was it after you fitted callipers?

    Was it after you fitted the discs?

    You must have run it with the OE discs? Was it vibe free?

    Has it always vibed but progressively got worse due to worn out bearings ?

    The front tyre will just simply amplify noise if it's really feathered.... 4K and you said it's squared off! less rubber = more noise transmitting through the carcass.

    I now thinks it's a combination of everything, until you can conclusively prove what changed!

    You sure it's not the chuckle pin that's connected to the laughter shaft inside the spodumene modulater!
     
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  15. Mr OCD

    Mr OCD Well-Known Member

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    I've got a good sense of humour chap but your starting to grind my gears with your comments. No real need for it is there?

    I'll figure it out. As I said I'll rule the discs out next as they are the 'unknown' in all this.
     
    #95 Mr OCD, Jul 7, 2017
    Last edited: Jul 7, 2017
  16. Dave dunlop

    Dave dunlop Elite Member

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    I've invested quite a considerable amount of time and effort to try and help you remedy your problems and point you in the right direction fella without any real gratitude from yourself, I've always been very thankful of other peoples Input and information they have passed on over the years! So personally don't take it to heart! I've the patience of a saint with most people and for most problems, trouble is your just not helping yourself by back peddling with all the other issues! I'm not trying to teach you to suck eggs but just have some kind of process you can work through..... I will stop grinding your gears or you going to need a Nova box! and leave you to work it out for yourself ...
     
    #96 Dave dunlop, Jul 7, 2017
    Last edited: Jul 7, 2017
  17. Mr OCD

    Mr OCD Well-Known Member

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    Put yourself in my shoes ... 4,000 miles ago due to vibration from the front end and with 25,000 miles on the clock I spent some money revamping the front end.

    - New tyres
    - Fork service
    - Used Brembo Oro discs (yes, history not known)
    - New calipers
    - New brake pads
    - New brake lines
    - New wheel bearings

    Vibration was gone. Job done.

    In the last thousand miles it's come back hence replacing the head bearings which resolved the issue for approx 50 miles although I suspect that was just the brakes setting in as previously discussed.

    So you can imagine at this point I'm coming up to having spent nearly £1500 and the issue still exists therefore somewhat frustrated.

    As for gratitude I apologise for that. If you knew me you would know that I'm always grateful to those that help and offer advice and that I have gone out of my way in the past to help members on here and elsewhere on forums often at my own cost. I do appreciate the help and I certainly have a few avenues to pursue to get to the root of the problem.
     
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  18. sp1n99

    sp1n99 Active Member

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    Wow! Are you two a couple?
     
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  19. Dave dunlop

    Dave dunlop Elite Member

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    Apology excepted so let's just move on.....

    Running through your list and eliminating the parts you have changed is your only hope, Now your in a position knowing all your bearings are fine, callipers are all good with new pads, just out of interest have you ever had your wheels repainted? I.e. Stripped or coated? I have heard of cases where they have painted or coated over the machined face the discs sit against. You have pretty much covered all other areas now so I would sit it out and wait for your discs to arrive, the only thing I'm going to mention is make sure both your tyres ane tip top and well balanced! Don't think that's part of your issue but it can cause some strange feelings and noise. Try riding with unbalanced wheels and you will see what I saying..... everything we do on are bikes is via the tyres that's why it's paramount there all good and it's fundamentally along with brakes the most important part of your bike.

    Btw ..... I will still take that tenner if it is the disks:D:D
     
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  20. Mike07

    Mike07 Active Member

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    Take a breath old bean. I think you're doing really well. These problems are so bl**dy infuriating I'm amazed you've not taken a hammer to it, it's especially worse for you, the bike being your commute. I understand that you are thinking 'out loud' when you're mulling over the points and subtleties of the various issues that are in the complex mix of your deep understanding of the problem. Unfortunately a solution is not obvious, or you would have solved it long ago. It’s also maybe a combination of factors, when attempting a solution it’s easy to change more than one thing at a time, further confusing the issue.

    Perhaps it’s time for a new set of eyes on the job. The problem is finding someone that really understands suspension and not just a shoot from the hip chancer, that does nothing but cost you money. Perhaps someone knows a professional suspension engineer who has a good theoretical and practical knowledge in this field. You seem a good 'tools' man yourself but sometimes a new set of eyes are needed.
    Let's hope it's the discs tho....:)
     
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