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zeebot
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1,125 Posts
Discussion Starter · #1 ·
I just had a new bike built up at a local shop and i'm about 99% sure when bleeding and changing over my brakes oil got on the rotors and pads.

the rear squeals VERY loud and has a squishy lever with terrible stopping power....it's an awful sound not the normal squeal you hear from a disc brake. painfully loud.

the front squeals as well, has good stopping power though and the lever is fine so i assume it got only a little bit on it.

basically what i want to know is what steps you suggest i take.

The main issue here is i have a big race next sunday and this HAS to be fixed by then be it buying a completely new set of brakes.

obviously i'm going to call the shop tomorrow to inform them of what happened. they tried to tell me it was the alcohol on the pads and rotors and it needed to be burned off. I use alcohol every day where i work cleaning sterile hoods at the end of the day and know how fast it evaporates so i dont see where 'burning it off' even comes into play.

should i demand new pads only? pads and rotors?
 

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Registered
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938 Posts
Can't help you about the noise, but...

If the rear lever feels squishy, then it sounds to me that you've got air in the line. That may be the sole reason for the lack of power back there too, not contamination. Although I suppose it's possible you have a bum seal on one of the rear pistons (which let in air), and oil has leaked out onto the rotor and pads. If contamination is a problem, you should certainly be able to clean the rotors. I'd try taking the pads into work and soaking them in hexanes or toluene or whatever hydrocarbon solvent you've got lying around. That should remove any mineral oil (assuming it doesn't damage the pad or delaminate it :eek: ). Or you can try the blowtorch method. Personally, I'd use a bit of solvent.
 

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Do It Yourself
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5,720 Posts
That sucks!

You can try burning the contaminants off but best bet is new pads. If the shop was the one that contaminated the pads, they should be buying you some new ones! Rotor can just be cleaned off with alcohol or whatever solvent you have handy. Just make sure to use enough to clean out all the crevices and wipe clean. This might take a couple passes to get all the holes and all.
 

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zeebot
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1,125 Posts
Discussion Starter · #4 ·
Homebrew said:
You can try burning the contaminants off but best bet is new pads. If the shop was the one that contaminated the pads, they should be buying you some new ones! Rotor can just be cleaned off with alcohol or whatever solvent you have handy. Just make sure to use enough to clean out all the crevices and wipe clean. This might take a couple passes to get all the holes and all.
I actually have new information today that I should pass on. I called magura before calling the bike shop so i knew exactly what i would need to ask for and to confirm that was probably the reason my brakes had turned to crap. Lonnie told me with marta's when you put them on a new bike the pads will be hitting the rotor in a different place most likely causing the problems. He also asked me if i faced the tabs. my old frame i didnt face the tabs and i hadnt faced the fork either. i had both faced during installation this time. apparently this will also cause the problems i had so couple the facing with the new frame and i was bound to have issues.

so, i ordered new pads myself today and will just clean the rotors with alcohol to be sure tomorrow when i get the pads.
 

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just along for the ride
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3,033 Posts
Get a .99 cent can of spray brake cleaner should get the oil off the caliper/pads but sounds like your rear brake will definately need to be rebled if the lever is spongy or not returning to the stops after use. Could be air in the lines if the air is in the caliper you will be getting vapor locking when your pads heat up. I'd take it back to the shop first if they did the work.
 
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