rear brake problems

[gamorg02]

I'm ready to kill someone with all the problems i've had with my damn rear rim. aside from some damper issues and others, this is just the brake problems i'm having....

looking to rant/advice, whatever people wanna throw out there..

background:

put 400 miles on vmax then put her away for the winter. got the rims powdercoated. brought the rims to a shop, they disassembled and brought to p/c and re-assembled.
this summer i got a galfer rear rotor as i hate the stock one. when i went to put it on, one of the holes was stripped bad so the bolt went in sideways and the ledge that bolt went into was about 0.005" lower than the rest. machine shop verified, put a helicoil in and lowered the other ledges to match.

brought the rim home, put it on the bike, worked great. squeaked for a few miles and then it was good. until the weather got colder:bang head::bang head:

now:

in the past couple weeks as the weather got cold, the rear brake would start squeaking. sometimes constant, other times like as certain parts of the rotor went through the caliper/pads. Seemed whenever i tried to stop as the noise was just coming on (to see where on the rotor the issue lied) the valve stem was at the bottom of the tire (ish) . ALso should note this only happens with medium pressure on the pedal and under 10 mph. putting the bike on the center stand and rotating the wheel forward without brake doesn't reproduce. At certain points it would squeak, with no pressure and i had to turn the wheel backwards.

talked to galfer, got a dial indicator on the rotor @ the machine shop that did the original bolt hole/ledge work, it had 7 thousands ish of runout on the rotor. that's over twice what is in galfers' acceptable limit. They said to send it for inspection. Before I did that mike (on the forum) let me use his old rotor and pads off of his bike that had 65k miles on 'em. not the best but better than nothing (thanks again man)...

put them on last night and last night and today until about 10 miles from getting home everything was great. thought i just had a warped galfer rotor. then the squeaking comes back. same slow speed, medium or more pressure. it also seems that when i try to see what part of the rotor is making the noise the valve stem is back on the bottom!(pointing at the wheel being the culprit here) also put the wheel on the CS again and there are spots where its squeaking when rotating backwards. i can't be sure if its at the same spots, as i'm a moron and didn't mark which parts on the rotor (still has the high and low marker marks on it) went to which holes on the wheel.

so i also ordered a spare ebc rotor and pads incase i needed them, as if galfer gave me a new rotor iw as probably going to switch to EBC.

plan:
so my plan as of now is to try to go back to the machine shop and get the runout on the new (old stock rotor) measured along with making sure the wheel & ledges are true. if the wheel is off or something i guess i have my answer. maybe one of the ledges wasn't machined down properly. i'm not sure. i'm hoping its something obvious and easy to fix.


one last note, when i was putting the rotor/pads from mike on the rear, the pistons on the claipers were hard to push in. cleaned them thoroughly before i tried but it took me a while.
i'd say its possible they're not returning right but theres no drag and if they weren't returning right i gotta imagine it wouldn't be a rotational noise but more constant.

i also have some oem anti-squak backing metal things i could try but ran out of time.

anyways thanks for listening. any advice, thoughts, let me know....:bang head::bang head:

 

[one2dmax]

The pistons may not be retracting when you let off the brake if they were hard to push in. Sounds like you may want to take it apart and clean the pistons up and reassemble. I even polish the pistons when I do that.

Sean

 

[dannymax]

+1 If you're getting the same noise with a different rotor & pads it sounds like the only component unchanged is the caliper. There is a OEM rebuild kit available, hone out the clyinders, as Sean said, polish the pistons and install with new fluid.
Is there any chance there is a bit of water or old fluid hanging out in the bottom of the caliper?

http://www.ronayers.com/browseparts.cfm?SearchString=31A-W0047-00-00&adv=5&kw=fiche.ronayers.com

 

[one2dmax]

May not actually need the kit. Just take it apart and clean the heck out of it.

Sean

 

[gamorg02]

i was wondering if i needed the kit...

way to work this morning, no squeaking. ugh. except one certain spot.

let me run this by you guys though, it always seems to squeak, when turning the wheel, in specific spots, doesn't that kind of point to the rotor though?

previous rotor had more runnout that galfer wanted to see, so the rotor was acting up (at least on the wheel) as well.

Sean, just use a bunch of brake cleaner on all the parts?

 

[dannymax]

i was wondering if i needed the kit...

way to work this morning, no squeaking. ugh. except one certain spot.

let me run this by you guys though, it always seems to squeak, when turning the wheel, in specific spots, doesn't that kind of point to the rotor though?

previous rotor had more runnout that galfer wanted to see, so the rotor was acting up (at least on the wheel) as well.

Sean, just use a bunch of brake cleaner on all the parts?

It could, but if Mike didn't have a squeal with this rotor it really leaves only the caliper as the offending part. It's easy enough to rule out with a good cleaning and if you chose...the seal kit.

Unless the shoulders the rotor sits on weren't machined properly....which is kinda unlikely.

 

[gamorg02]

It could, but if Mike didn't have a squeal with this rotor it really leaves only the caliper as the offending part. It's easy enough to rule out with a good cleaning and if you chose...the seal kit.

Unless the shoulders the rotor sits on weren't machined properly....which is kinda unlikely.

before i did all that i was gonna see if i could swing up to the shop and see if the High/Low pattern matched the other rotor and make sure the wheel is true.

unfortunately i have no idea whats acceptable for runout on a wheel

 

[one2dmax]

Just use brake cleaner and or soap and water in the house. Then polish the pistons. You can use some scotchbrite or fine grit paper to clean the core of the housing (with the seals removed) and that will be fine in there (the piston does not rub on those areas so it's not as critical as the piston itself.

Sean

 

[gamorg02]

how do u polish the piston?

 

[[email protected]]

how do u polish the piston?

Aww c'mon! You're making it all too easy for us to make fun of you Garrett, LOL!!

 

[gamorg02]

Aww c'mon! You're making it all too easy for us to make fun of you Garrett, LOL!!

it coulda been worse! i know i know.
ok, rewrite.

if someone took the piston out of their brake caliper how do you polish it up?

 

[zippo6]

it coulda been worse! i know i know.
ok, rewrite.

if someone took the piston out of their brake caliper how do you polish it up?

*snicker*

 

[one2dmax]

Just like you would on the scoops but you don't need to sand it first. Just get the polishing wheel and the compound and buff it shiney. You don't need to clean the inside bore of the piston, just the outside that the seals ride against.

Sean

 

[gamorg02]

ok thanks guys.

i actually have a new plan. going to buy a dial indicator from harbor freight tonight. $20 with the clamp mount. i'm going to check the rotor myself. if i'm seeing like 6/7 thousandths of runnout i don't think its the caliper. still doesn't mean that wouldn't help

anyone know what lateral runnout is considered ok? i mean obviously 1/4" would be atrocious and cause all sorts of problems but where is the lin.

 

[jedi-]

I'll bet your Galfer rotor is fine as is the stock one as you're getting runout at the same position each time in relation to the wheel.
The Bozo's who machined your wheel haven't machined it flat.
Run the dial indicator on the rotor mount face with the rotor off and there will be the problem. Another check is to clock (dial indicator) with the rotor on and mark the high spot on the rotor, rotate it a couple of bolt positions and clock it again.
If it was warped , the high spots would always be on the same spot on the rotor.
But because I believe your wheel is the culprit, the high spot will now be in a different place on the rotor as you have rotated it.

 

[dannymax]

Jedi...What would be acceptable variance in the rotor face mounting shoulders?

 

[gamorg02]

I'll bet your Galfer rotor is fine as is the stock one as you're getting runout at the same position each time in relation to the wheel.
The Bozo's who machined your wheel haven't machined it flat.
Run the dial indicator on the rotor mount face with the rotor off and there will be the problem. Another check is to clock (dial indicator) with the rotor on and mark the high spot on the rotor, rotate it a couple of bolt positions and clock it again.
If it was warped , the high spots would always be on the same spot on the rotor.
But because I believe your wheel is the culprit, the high spot will now be in a different place on the rotor as you have rotated it.

i would tend to agree but:

the squeak has stopped, no idea how or why but its gone. had the bike up on the center stand yesterday and there was a tiny squeak when rotating backwards but it was in a different spot now.

picked up the dial indicator, worked great, about 3 mils variance on the rotor, not much more. what i need to do is test it once it squeaks again (if it does)

jedi, if i was to test the rotor mounting ledges, how would i do that? with pressure on the dial indicator it would bounce in and when it tried to go back onto the ledge for the next one it would surely moveit a bit. do i set it so the needle poitn of the indicator is barely resting on the ledge, so maybe it could push down another 10 mils or so? i'm thinking thats the only real way to test.

but if the squeaks still don't happen or move to where they were (opposite valve stem) then maybe the old rotor/pads needed time to meet.

i also have no reason to doubt these guys, they are a motorcycle machine shop, and have done a few things for me which have all been done right, and they caught one of the original issues themselves. not to say people dont make mistakes, but i'll have to see if the squeak comes back first eh?

 

[dannymax]

i would tend to agree but:

the squeak has stopped, no idea how or why but its gone. had the bike up on the center stand yesterday and there was a tiny squeak when rotating backwards but it was in a different spot now.

picked up the dial indicator, worked great, about 3 mils variance on the rotor, not much more. what i need to do is test it once it squeaks again (if it does)

jedi, if i was to test the rotor mounting ledges, how would i do that? with pressure on the dial indicator it would bounce in and when it tried to go back onto the ledge for the next one it would surely moveit a bit. do i set it so the needle poitn of the indicator is barely resting on the ledge, so maybe it could push down another 10 mils or so? i'm thinking thats the only real way to test.

but if the squeaks still don't happen or move to where they were (opposite valve stem) then maybe the old rotor/pads needed time to meet.

i also have no reason to doubt these guys, they are a motorcycle machine shop, and have done a few things for me which have all been done right, and they caught one of the original issues themselves. not to say people dont make mistakes, but i'll have to see if the squeak comes back first eh?

If it's only out 3 mills you're good to go!! You've already checked the mounting shoulders by clocking the rotor as the rotor is torqued to the shoulders....no need to go any further!

You can check the mounting shoulders by pushing the needle indicator in as it approaches the next shoulder, the gauge must be stationary for this.

The fact that the squeal position moved seems to go back to the caliper/pad being the source tho.

danny

 

[gamorg02]

If it's only out 3 mills you're good to go!! You've already checked the mounting shoulders by clocking the rotor as the rotor is torqued to the shoulders....no need to go any further!

You can check the mounting shoulders by pushing the needle indicator in as it approaches the next shoulder, the gauge must be stationary for this.

The fact that the squeal position moved seems to go back to the caliper/pad being the source tho.

danny

what if one was off tho danny, wouldn't the 5 being torqued down probably overrule that, or ya think it would bend at that point anyways? i know the galfer definitely would but i'm not convinced the stock one would.

i think with an indicator tho, just the force of pushing it is enough to throw off the reading from one to the next. when we're talking about 2x the thickness of a sheet of paper, those little forces translate. i can try tho.

well as of right now too, no squeal so i can't make any determination. hah.

 

[dannymax]

what if one was off tho danny, wouldn't the 5 being torqued down probably overrule that, or ya think it would bend at that point anyways? i know the galfer definitely would but i'm not convinced the stock one would.

i think with an indicator tho, just the force of pushing it is enough to throw off the reading from one to the next. when we're talking about 2x the thickness of a sheet of paper, those little forces translate. i can try tho.

well as of right now too, no squeal so i can't make any determination. hah.

The mounting surfaces are cut as the wheel is turned, so if the wheel wasn't chucked up straight the shoulders would be slightly higher on one side tapering down to slightly lower on the other, and any rotor mounted on them would be flat in relation to the shoulders, but tilted in relation to the wheel. You wouldn't get just one shoulder being lower than the others.