The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Luke D. on March 11, 2014, 12:38:46 PM
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HI everyone, my front brakes squeal when I use them, has anyone else had this problem? I have cleaned both the rotors and the pads, pads are still good, a few times but they still squeak. Any help is appreciated. Thanks
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Are the pistons retracting properly as tested by an absence of drag when you rotate the wheel by hand ? Dragging pads tend to glaze up and squeal.
If the pads are dragging then a caliper overhaul may be needed or you could just try exercising the pistons. Remove the wheel or caliper (doesn't matter which) and compress each piston with a G cramp and then carefully push them out again with the brake lever. Not a bad idea to put something the same thickness as the disc in between the pads so you don't risk pushing them out too far. Also beware one piston is likely to move before the other and may need to be restrained with the G cramp. Exercising the pistons like this a few times may free them up enough that they retract on the seals properly.
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Thanks Barry for getting back so quick. My bike is hibernating for the winter but I will take note of your suggestion and try that once winter is done.
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When I first got my bike the the front pads were new and squealed a lot. After asking around someone suggested just using them hard a few times to break them in. I put them on as hard as I dared on an empty road at a good speed a few times and the squeal is gone and has not come back.
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Alright, thanks David, I will try that one as well once all of the white crap is off the ground.
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Replace those squeakers with organic EBC pads and ride happy n' noise free.
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IF you do replace the pads, do go with the organic pads if you are using the stock stainless steel rotors. Sintered/metallic pads are totally incompatible with themf and you'll ruin them in short order if you do.
Once new pads are installed, it is preferable to be able to find some paved back road with little/no traffic on it so you can do bed the pads in properly by accelerating to ~30-40 MPH and then applying the brakes hard. As soon as the bike is just about to stop, release and accelerate again. Repeat 8-10 times. You don't want to give them a long time to cool off in between braking sessions. This helps the pads to settle into their positions and not glaze with gentle application of the brakes when they are new.
You could also do this if you have plenty of meat on your existing pads, and just take them off and scuff off any glaze they may have on their surface with some 80 grit sandpaper - then do the rapid stop thing as with new pads. If none of this solves it, you can try the spray goop (some even just use outdoor paint) to paint the BACK of the pads to help dampen vibrations/reduce squeal.
Make sure that you don't have a traffic cop on the road when you are wearing in the brake pads ;)
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Replace those squeakers with organic EBC pads and ride happy n' noise free.
Are they available for the pre-81 bikes? bmw2valve.com just seems to have them for the later bikes.
http://www.bmw2valve.com/motorcycle/B-7/7871098.html
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The pads shown in the picture, are for Brembo calipers .
I think EBC pads for the ATE calipers, are FA57 .
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Make sure you have no radial cracks on you rotor/s. Between the holes. That will make the brakes 'sing'. If you find any at all ditch the rotor.
Cheers
Rev Light
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I'm using the FA57 EBC pads on Ate calipers and have no squeaks except at very slow speeds when wet.
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Thanks all for the help. I think I still have the original pads on there since the bike has few miles on it. I remember buying new pads because I thought they needed replacing but there is still good meat on them. My rotors are still in great shape(no warping, cracking). Once I get my bike out of storage I will try these options and if all else fails I will just get new pads.
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Cleaning the pins and anti rattle springs up wouldn't hurt either. A little brake caliper grease on the backs of the pads could help the noise, but that doesn't "fix" the underlying problem. My brakes still squeal with EBC organics... perhaps I need to do a good deglazing of the rotors.
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... I think I still have the original pads on there since the bike has few miles on it...
"Thinking"...thirty-two year old OEM brake pads? The OEMs were never anything to write home about. Unless the calipers have been serviced, I'd bet the caliper pistons are also fouled with watery, gunked up hydraulic fluid. From a safety-of-flight issue, your brake system issues should be a Priority One. Not sometime later.
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My bike still had the original 28 year old pads when I got it but someone had kindly soaked the whole bike including the pads in some sort of rust proofing fluid so I had no choice but to change them.
Old pads could have deteriorated in other ways too. I once had the brake pad material shear off the backing plate when I was 200 miles from home - on a Sunday. Using only the rear brake all the way home was fun.
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...on a Sunday. Using only the rear brake all the way home was fun.
;D Kinda takes me back to the vintage Brit bike days trying to "whoa up" my '53 T100C.
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Regarding Front Brakes:
If I find my front brakes to be "soft", could this be a pad issue, or a caliper issue?
Last year, or was it two years ago (egad, I have been off the bike too long), I made a major change to the front brakes. I successfully transferred the dual front brakes of an '82 R65LS to my standard '81 R65. I also replace the Master Cylinder. I forget right now, but I did upgrade the cylinder size. I did NOT get the increase in braking I hoped for.
When I brake, it's still softer than I would like. So I am now thinking it's the caliper themselves. The question is, do they require simply pad replacement, a rebuild, or both.
Opinions? Thank you.
Dell
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Dell,
With the brake line connections for the two caliper setup, there's a few additional spots that may have a little air still trapped. It may take some close examinations and, perhaps, even removing a connector block or sumthin' to get the air to move on up the line.
There's been some similar brake bleed comments on another thread just recently. And what size master cylinder did you fit with the 2-disc conversion?
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If the brake lever is soft a good test is will the lever pump up. If it will that would suggest there is still some air in the system. If it still feels soft after pumping then there is probably some other cause.
A few years back I had a bizarre situation where a soft lever had resulted from inadvertently putting the pads back on the wrong side of the caliper. Because the pads had not been worn exactly parallel the disc was bending slightly on application of the brakes and then on release the pistons were being pushed back a little too far meaning they had further to travel on the next application of the brake and hence more travel on the lever. Does no harm to check by getting down close and watching exactly what happens to the pads when the brake is applied. It only takes a few extra thou of piston retraction to produce excess lever travel.
As for bleeding brakes if there is one trick to get all the air out it's pull the brake lever very very slowly and crack the bleed nipple only enough to get the fluid flowing. Maybe I have it easy with only one caliper but I can usually change the fluid at the annual service and achieve a firm lever without any drama and have a functional brake straight off. I still tie the lever back over night just to make sure.
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Actually, the lever is quite stiff. The bike just doesn't "stop on a dime". This is why I suspect caliper issues over line issues.
Sorry I used the term "soft". I understand how that caused confusions as to my problem. Issue is stopping speed and power. I don't have a problem with the brake lever or MC.
Thanks!
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You may want to deglaze the pads, scuff them up with sandpaper .
Try to do the same to the rotors if you can .
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That's certainly easy enough to try. Thanks!
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Thanks to everyone who has commented and given advice. Unfortunately winter does not want to loosen its grips on the upper midwest and we have been thrown back in. One day after the "first of spring" and we got about 9inches of snow and now after a week of "spring" we are getting 3-6 more today and tomorrow and maybe more next week. :'( Eventually I will be able to get my bike and then try these suggestions out. Thanks again.