My bike has been parked for about a week, pending receipt of the Haynes manual I ordered so that I could do a much needed replacement of the rear pads.
I got the new pads a few days ago, got the manual today, and went to town.
Here's the problem:
I got the old pads out after taking out the springs and pins, and they were VERY tight in there. It took some serious muscle to get them pulled out of the caliper.
Looking at them, there is no pad whatsoever on them...they are pure metal. :dunno_white:
The new pads that I got have a metal backing that is the same dimensions all around as the old ones...but there is pad on them.
So, of course, they are no where CLOSE to fitting into the caliper in place of the old pads.
My question is this:
Since I know I have the right pads (they were specifically listed for a GS500 and the profile is identical), is my caliper adjusted wrong? It really looks like someone may have tightened things up in there in order to make the bike stop on completely worn out pads (I bought it used about 2 months ago). If so, how the heck do I adjust it back to where it's supposed to be so that I can install pads that will actually do their job?
Here's a pic. The one on the left is what I just took out of my bike; the one on the right is the new pad.
That CAN'T be what a brake pad is supposed to look like...can it? I mean, that thing's had nothing but metal grinding on metal stopping this bike for God knows how long.
But the new one is nowhere close to fitting in the space that held the old one REALLY tight.
(http://i16.photobucket.com/albums/b42/Murf425/Picture.jpg)
Just did mine, were in basically the same shape. You have to get the pistons pushed back into the bores to be able to fit the new pats in. It can be a bear, but be careful not to scratch the pistons/bores/housing. I padded a set of channel locks w/ fuel line around the jaws, and used the old pad to push the pistons back. You have to push them back evenly all around, and they will slide right back. If the pistons get cocked or pinched/pressured all one one side, they won't go back into the bores.
new to bikes but on cars i use a C clamp with the old pad to push it back...sounds easier then going all the way around little by little.
I used some bar stock I had lying around, maybe 1/8th inch thick and about 1 1/2" wide. Probably 4 feet long. I bent it using my bare hands at a 45 degree angle, to clear the seat plastic.
Then I just used it as a lever against the brake rotor, making sure that the bar was pressing somewhere near the center of the piston. It helps if you loosen the bleeder valve, so you're not fighting the hydraulic pressure. What I did there is put a piece of hose on the bleeder valve and gave it a single pump, so maybe 2" worth of brake fluid came out, then left the valve cracked 1/8th inch: Just enough for fluid to come out, but not enough to suck air in.
The rear rotor flexed A LOT, which worried me, but eventually those pistons went back in. Everything's back together and I've ridden 200 miles, no problems. It's funny how much you stress about the project you're doing.... your bike feels broken. Then you go for a ride and in an instant, you no longer care about those goobered up threads, or that overtightened bolt :)
I wonder if your rotor is any good. Have you measured it?
Measured?
Sorry for the ignorance. This is my first bike.
There is a minimum thickness for rotors. For the rear it is 5.5mm
Since there is quite a bit of metal missing from the old pads, you can assume there is quite a bit of metal missing from the rotor as well. If you can get your hands on a micrometer, measure the rotor thickness. If you can't get a micrometer, take the rotor off and bring it into an auto parts store. They will have one.
U may as well bleed the breaks if u haven't in awhile when doing this.. it will make the pad change a lot easier.. my front pad looked like your bare metal one too, lol.
I've had the bike about two months, and from the looks of this project and the oil change I did last night, the previous owner never did ANY maintenance to it.
Quote from: murf425 on October 08, 2008, 07:12:34 PM(http://i16.photobucket.com/albums/b42/Murf425/Picture.jpg)
Holy shnikey...!
I'd be surprised if the rear rotor is any good after that.
Prying against the rotor or the brake arm is a bad idea. They weren't meant to be pried against, and while everything may look fine, there may be stress cracks. You don't want stress cracks on anytihng, especially a part of the braking system. ;)
Howto do it ? Here:
Remove the pins that hold in the brake pads, place em in a pie tin. You just ate that pie, and it was deeeeeeeliciouse , so you can afford expending a few calories on fixing your fooken brakes, right ? Cool.
Remove the cotter pin (you bess have on there !) on the brake arm that holds the nut snug and the caliper from falling off.
Gently pry the brake line holder away from the swing arm just enough to clear the brake line. GENTLY you behemoths !
Remove the two bolts that hold the brake caliper to the swing arm/axle/doo-hickey.
Gently pull up on the caliper, watch as your old crusty pads fall out, crap all over the place. Yeah !
Put a C clamp where those old crappy pads were, and gently push the piston back into the caliper's bore.
GET YOUR EYES OFF MY BISCUITS ! Them biscuits are for MY eating, not yer eyefulls ! You just had a whole damned pie ! Sheesh !
clean that mess up with a dry paintbrush. no need to spray it with anything. thanks.
put the mess back together, don't leave out the cotter pin in the brake arm assembly.
If you can't work a c- clamp, get yer neighbor's 8 year old and he'll figure it out for ya, but laugh at you every time you leave the house.
torque it all to spec, use some BLUE loctite, and enjoy the ride. take it easy till the pads conform to your FOOKED rear roter's ridges from those FOOKED old crusty pads you let run down past their sell-by date.
done. (assuming you know you should bleed your brake lines, both front and back anytime you do this)
Quote from: ohgood on October 09, 2008, 01:41:03 PMPut a C clamp where those old crappy pads were, and gently push the piston back into the caliper's bore.
I retract the pistons with the old pad in place; I find they're easier to get a grip on. YMMV. :)
OMG its the Wiki!!!
:icon_mrgreen:
http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/BrakePads
To replace the rear brake pads.....I can do it with the rear caliper staying attached as well as the rear wheel..correct?
That is how it's shown in the GS500 Wiki.....http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/BrakePads (but the rear wheel is off)
I do not want to take off the caliper for sure....the job is simple enough as it is with the caliper in place. I'm waiting for the new brake pads to come in.
2. It's a 2007 and I'm changing the pads on it... :dunno_white:....the problem.....I can see the rotor disc is really worked...the pads were rubbing against it constantly and eventually wore out. Is it possible the piston is stuck? Will I be able to move it back for sure?..to make more room for the new pads...
With the bike on the centerstand and rotate the rear wheel freely...I can hear the contact of pads and disc.....no major warps in the disc though
I'm just going to change the pads, push the caliper back and put the cover back on....should I look out for anything else regarding my problem?
bummmp pls helpp...duno why the brakes were constantly rubbing the disc causing the brake pads to wear outtt...its an 07! takes much longer than that to change brake pads, thr front are more than fine
Quote from: vorBH on March 07, 2009, 10:10:36 AM
To replace the rear brake pads.....I can do it with the rear caliper staying attached as well as the rear wheel..correct?
That is how it's shown in the GS500 Wiki.....http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/BrakePads (but the rear wheel is off)
I do not want to take off the caliper for sure....the job is simple enough as it is with the caliper in place. I'm waiting for the new brake pads to come in.
2. It's a 2007 and I'm changing the pads on it... :dunno_white:....the problem.....I can see the rotor disc is really worked...the pads were rubbing against it constantly and eventually wore out. Is it possible the piston is stuck? Will I be able to move it back for sure?..to make more room for the new pads...
With the bike on the centerstand and rotate the rear wheel freely...I can hear the contact of pads and disc.....no major warps in the disc though
I'm just going to change the pads, push the caliper back and put the cover back on....should I look out for anything else regarding my problem?
Take your caliper off the bike and have a look. It is really not that hard to take it off and just flip it to the outside of the bike without taking the brake line off... Check to make sure your caliper isn't sticking. Also, if your brakes really are rubbing all the time, check to make sure your rotor is still good. If it rubs all the time, it could overheat and warp, or get grooves in it. If you put new pads on the bike with a grooved rotor, they will get grooves right away and when you finally do replace the rotor, you'll also have to replace the pads again or the grooved ones will squeal like freakin' crazy and drive you insane.
Thanks for your reply! Phew, good, I didn't want to take off the brake line....Ok so if it is sticking, I need to lube the piston at least right?
I found a product at Walmart...a Brake Cleaner, like $4.44 CDN...says it is applicable to all parts of the brakes and caliper etc..can I use this to make a piston smooth?
Also, the rotor is pretty worked up rough from all the rubbing....should I have it machined at the mechanic?...but this requires taking off the rear wheel etc...a headache....but a must do??
There are minor warps in the rotor..you can hear contact.....but it rotates freely....possibly because there is no padding left..I think when I put in the new pads it won't rotate as freely because it'll be contact actual brake pad...any suggestions??
My rear brakes squeak quite a bit anytime i step them. is this something I should be worried about or should I just let it go? would changing the pads help any? could it be possible that at one point the pads were down with the wheel being a lil crooked and now with it straight its squeaking? I've felt the rotor, i havent felt any grooves.
our bike is known for brake squeeking
when i hear people's brakes squeaking on their cars, i kinda judge them in my head that they're lazy and just don't care about their car. I can't but think that other people who hear me are doing the same thing about me. I dont like to be perceived the wrong way, even by people who i'll never see again. but i suppose i can live with it. I was just hoping that there was some sort of quick fix.
Minor sqweeks are okay my neighbor mechanic said....I have a practically new 07 cbr125.....the brakes still touched a bit and it was new....but when it prevents rotation of the wheel etc that's a problem.
Anyways, I checked my rear rotor...the area where the pads press against it is eaten away maybe 1mm?? There's no padding left on the pads...is the piston seized? I pushed apart the pads but it made it worse because it pushed from the top of the pads, causing the bottom of the pads to invert inwards on the rotor...BUT the purpose was to see if the piston would move...and its moving
I realigned the wheel, its much better now...BUT the rotor is ruined and I need to have it machined
Heres the concern...I'm going to get the new brake pads...so I'll take out the worn ones and try to push the piston back to put in the new pads....when it's all setup again though and I pump the brake again to push the pads in closer to the rotor....will the pads get killed again because of the condition of the rotor both through use and non-use?
Really need some help, thanks guys
There is a simple test that will determine if you have sticking piston. Place a thin feeler gauge between each pad and the disc. Then stamp hard on the brake pedal and try and pull the feeler out, if to does come out the piston is sticking, if it doesnt the piston is free.
As for your disc.....Suzuki quote a service limit thickness of 5.5mm, not much when a new one is about 6.1mm and if you have lost 1mm off each side you are well outside tolerance even before getting it skimmed.
Oh ok...well it's not 1mm I've lost, just an estimate...I'd say .4 of a mm I don't really know.........all I knwo is that I am probably going to be machining the rotors (both sides) to get it back to a normal smooth surface
Quote from: vorBH on March 08, 2009, 04:06:41 PM
Oh ok...well it's not 1mm I've lost, just an estimate...I'd say .4 of a mm I don't really know.........all I knwo is that I am probably going to be machining the rotors (both sides) to get it back to a normal smooth surface
Good luck with that. From what I've seen though, as soon as the rotor isn't smooth anymore, it is worn too thin to be machined back in to place. Even if you could barely squeak by and machine it just inside of tolerance, you'd just have to replace it anyways in a short time... Sounds like time to go rotor shopping to me. Changing the rotor isn't that bad, the hardest part is getting the wheel aligned and the chain tension right when you're done, but if you do the chain slack adjustments when you should, you'll already be able to do this...
Ok cool, thanks for the info...I guess I'll measure the rotor thickness (5.5mm minimum), and see where it's at.
In the meantime...where can the rotor for cheap price?
Do I have to get the same one? Or will something else thats cheaper fit? (a 4 bolt pattern)
heres prolly the cheapest youll find unless you go with someone elses gs take off
http://gstwins.com/gsboard/index.php?topic=46773.0
Thanks! I sent him a PM
ok thats prolly the best deal youll find on that rotor.
Quote from: John0 on March 08, 2009, 10:03:31 AM
My rear brakes squeak quite a bit anytime i step them. is this something I should be worried about or should I just let it go? would changing the pads help any? could it be possible that at one point the pads were down with the wheel being a lil crooked and now with it straight its squeaking? I've felt the rotor, i havent felt any grooves.
Do you still have braking response? (dose it take alot of effort for the brake to stop the bike)
If your not getting much stopping power than it think it is time for a change. I just changed my back one after they were squeaking when i applied them at low speeds. i had next to no pad left on them and couldn't stop with the back brake very well at all.
So as described before....my 2007 gs500F....rear rotor is all rubbed down by the pads, no pads left...right down to the metal plate of the brake pads....is the caliper seized?
What should I do to fix it? Open the caliper....lube everything in there (piston)?....and then go ahead and install the new pads?
Which brake/caliper lube should I use?
ALSO, may it be the case that the rotor is not straight, ie. running on an angle....but if the chain tension indicators on both sides are equal then the wheel must be straight along with the rotor....
When I spin the wheel...at half the spin there is no resistance.....the other half the rotor resists and rubs the pads...
Quote from: vorBH on March 26, 2009, 12:17:09 PM
So as described before....my 2007 gs500F....rear rotor is all rubbed down by the pads, no pads left...right down to the metal plate of the brake pads....is the caliper seized?
What should I do to fix it? Open the caliper....lube everything in there (piston)?....and then go ahead and install the new pads?
Which brake/caliper lube should I use?
ALSO, may it be the case that the rotor is not straight, ie. running on an angle....but if the chain tension indicators on both sides are equal then the wheel must be straight along with the rotor....
When I spin the wheel...at half the spin there is no resistance.....the other half the rotor resists and rubs the pads...
Hmm, that sounds like all kinds of not good. If your rotor is rubbing things while the wheel is straight, I'd first suspect that it is warped. If you have a seized caliper, it is not at all difficult to imagine that riding around with the brakes rubbing all the time warped the heck out of the rotor by overheating it. If the rotor is mounted wrong, I guess it could be wobbly without being warped, but if it has been on there long enough to eat through all of a brake pad, it is probably toast no matter what the root cause of the problem was. If I were you, I'd probably replace the rotor, get new pads and rebuild the caliper. When you install the new rotor, make sure the mating surface on the wheel is very clean and flat and doesn't have anything there that would cause your rotor to not seat correctly.
I just rebuilt my front caliper on Tuesday and I can tell you with confidence that it isn't hard. You will probably need a source of compressed air to remove the pistons (heed the warnings in the service manual, they really do shoot out quite violently!) but no other special tools are needed. It did take me a few hours of scraping and an entire can of brake cleaner to get all of the corrosion and dirt out of the seal grooves that caused my seals to go bad in the first place, but that was more tedious than it was hard. Once you've cleaned the cylinders and pistons and convinced yourself they're not worn beyond spec, just stick new seals in and reinstall the pistons. For lubrication, you just use clean brake fluid. Also, if you don't have stainless brake lines and haven't changed your brake lines in the last couple of years, now would be a really good time...
Fred, I'm amazed how many folks are having such problems with almost new bikes.
I would strongly guess the root cause here is he has been adjusting his chain tension incorrectly, leaving his rear axle crooked, causing his back brakes to wear-out prematurely and f$$king-up his rotor in the process.
People, when you adjust your chain, leave a little slack in it, and MAKE SURE THE AXLE IS ALIGNED EVENLY ON BOTH SIDES.
Yeah, it could be a poorly aligned wheel, but if he's confident the alignment is right on, the next likely candidate is a stuck caliper. A stuck caliper is probably a pretty easy problem to end up with if the bike sits for a very long time and the fluid and lines aren't changed often enough... It is weird that people have problems with new bikes though. My '94 with about 88,000 miles on it doesn't have such problems. I wonder what's going on. I guess it could be any one of a few things: quality could be decreasing, all the bikes that were built wrong in the 90's have long since died horrible deaths just like these new ones, or perhaps this kind of thing happens all the time to GSs that sit, but only people with newer bikes complain while the guys with older bikes just chock it up to old age and fix it. I don't know...
QuoteI would strongly guess the root cause here is he has been adjusting his chain tension incorrectly, leaving his rear axle crooked, causing his back brakes to wear-out prematurely and f$$king-up his rotor in the process.
This is wrong...I bought the bike in November..put it away until March (now)....(its an 07)..when I bought it the chain had too much slack in it...in early March I tightened the chain to have ~1.2 inches slack....and both ticks on the chain adjuster to align the wheel are even.
SO, the previous owner f%&ked it up, I don't WHAT the f**k she did and it kinda pisses me off....anyways.....I'm going to take it to a mechanic, have the rotor machined, and open the caliper and re-grease it etc...and then re-install everything with the new brake pads.
I opened the rear brake resevoir and the fluid is clear and clean.
What do you mean by "For lubrication, you just use clean brake fluid"...you mean actual DOT brake fluid to lube all the parts in the caliper?
Yes, you use DOT brake fluid to lubricate the inside of the caliper. You don't want anything in there that isn't brake fluid. Also, you can't machine motorcycle rotors. They aren't thick enough. The difference between a new rotor and a worn rotor is .7mm max! By the time you've got a problem, you've already worn the rotor beyond limits. Time to just get a new rotor.
Hmm Out of curiousity...what happens if I don't get a new rotor?
So I would just open the caliper, get it unstuck, replace the pads, make sure the wheel is definitely straight........if the rotor is below recommended thickness, will it warp, or? whats the problem with it being under a certain thickness?....I'm thinking to just leave it since I rarely use the rear brake....
Will the current rough surface of the rotor (currently it is very rough on the inside of the rotor) ruin the new brake pads??
Quote from: vorBH on March 27, 2009, 03:00:44 AM
....I'm thinking to just leave it since I rarely use the rear brake...
You have been given answers to this issue by several people but are ignoring them and instead looking for justification for not doing what is being recommended :dunno_black: With this in mind I am not too surprised to read the above comment...........If you dont use the rear brake why not take the whole thing off, junk it and solve the problem that way???!
Your pads are worn, there is no friction material left...replace them.
Your disc is worn and is below what Suzuki says is a safe limit, it could warp even shatter in use and the damaged surface will rapidly wear out new pads. If you carry on using it and you are putting yourself and more importantly OTHERS at unnecessary risk....replace it.
Something could be out of alignment or your caliper could be seized or the pads could be hung up on the pins, no-one knows for certain because no-one has actually seen it and from your description its impossible to say with certainty. Your pads could simply have had a hard life from new and died a natural death. It will become obvious if something is siezed when an attempt is made to replace them and at the same time alignments and chain tension can be setup and checked.
OR........you can carry on asking the same questions and ignoring the facts/advice until some Numpty comes along and gives you the answer you WANT to hear.
You Numpty obviously don't understand the simple concept of a Forum...a place to ask questions and discuss things...we're all at different knowledge levels
With your attititude, go take a hike
You have asked for advice, you have been given it by several people, and you are ignoring it.
Your bike, your life, your choice Pal.....get on with it :D
Quote from: vorBH on March 27, 2009, 03:00:44 AM
Hmm Out of curiousity...what happens if I don't get a new rotor?
So I would just open the caliper, get it unstuck, replace the pads, make sure the wheel is definitely straight........if the rotor is below recommended thickness, will it warp, or? whats the problem with it being under a certain thickness?....I'm thinking to just leave it since I rarely use the rear brake....
Will the current rough surface of the rotor (currently it is very rough on the inside of the rotor) ruin the new brake pads??
You probably don't want to do that. Of all the things on your bike, tires and brakes are the two things you absolutely cannot cut corners with. You need to guarantee that your brakes do what you need every time you go for them. With a below spec rotor, you will not get full braking and if it is in any way warped or grooved, you will quickly destroy new pads. On a motorcycle you have so little room for error you just can't afford to let things like this go unattended. If you want a concrete example of why you need your back brake working at all times, here's a personal experience from a couple of weeks ago: I pulled out of the parking lot on the way home from work a couple of weeks ago and when I grabbed the front brake, there was nothing. The lever went to the handlebars without even slowing the bike down. I had good back brakes, so I could stop, but if they weren't up to snuff I could have been in even worse trouble. Turns out the front caliper had corroded too much and the seals weren't effective anymore. This kind of random failure is exactly why you need to make sure you have a good backup. Also, if you never use your back brake, when you replace the rotor and pads and make sure everything is running right, you'll have a back brake and it wont' wear out. The $200 in parts you need to fix this right will be much much cheaper than the consequences of even the most minor brake failure. You have to make sure that your next panic stop ends with you stopped, not you finding out that your second set of brakes has failed and you cannot avoid hitting whatever it is that made you panic in the first place.
Thanks for the info, that was very helpful. For sure, Tires and Brakes #1 at most.
I bleed out the rear brake fluid today, pushed back the pistons, put in the new pads...but theres no pressure in the system yet because I need to put brake fluid back in/refill.
Only the inner brak pad was severely worn in PAST the metal plate too!!!...almost as if the wheel was running angled or something...the previous owner did not tighten the chain...the chain was so loose when I got it...like if no 2inches or more of play
I just put in the new pads to go get the safety certificate and transfer the licence plate and get that over with so I can ride legally.....after I will re-open the caliper and lube it up and also go to the mechanic to figure out the deal with the rotor....keep you posted, and really appreciate the help, thanks guys!
Pads in most cases will not wear even, 1 pad will wear more than the other one or at least that has been the case on all my bikes.
If the pad wears uneven EG the pad wears on an angle then this is a good indication that the piston needs a clean and lube up to make it move evenly and without effort. OR the pad has not been fitted correctly.
:thumb:
Oh by the way....You may want to learn HOW to use your rear brake as well or one day you will end up down the road rag doll style. M/cycles have a rear brake to help you pull up and stop. The rear brake also keeps the rear end of the bike in line under heavy braking. Not a smart idea to not use the rear brake.
Quote from: sledge on March 27, 2009, 04:13:13 AM
Quote from: vorBH on March 27, 2009, 03:00:44 AM
....I'm thinking to just leave it since I rarely use the rear brake...
You have been given answers to this issue by several people but are ignoring them and instead looking for justification for not doing what is being recommended :dunno_black: With this in mind I am not too surprised to read the above comment...........If you dont use the rear brake why not take the whole thing off, junk it and solve the problem that way???!
Your pads are worn, there is no friction material left...replace them.
Your disc is worn and is below what Suzuki says is a safe limit, it could warp even shatter in use and the damaged surface will rapidly wear out new pads. If you carry on using it and you are putting yourself and more importantly OTHERS at unnecessary risk....replace it.
Something could be out of alignment or your caliper could be seized or the pads could be hung up on the pins, no-one knows for certain because no-one has actually seen it and from your description its impossible to say with certainty. Your pads could simply have had a hard life from new and died a natural death. It will become obvious if something is siezed when an attempt is made to replace them and at the same time alignments and chain tension can be setup and checked.
OR........you can carry on asking the same questions and ignoring the facts/advice until some Numpty comes along and gives you the answer you WANT to hear.
That is a bit harsh, i think he is asking very valid questions. I don't think he would be ignorant enough to leave the brake as it is. I like to know the repercussions of my actions before i actually do it. A smart man learns from his mistakes, a wise man learns from others.
QuoteThat is a bit harsh, i think he is asking very valid questions. I don't think he would be ignorant enough to leave the brake as it is. I like to know the repercussions of my actions before i actually do it. A smart man learns from his mistakes, a wise man learns from others.
Thanks man, thats what I was doing, just shooting at what-if situations to see it from every angle and to really know what I left with...
Just like the other day in class, the Tuturial leader for a class presented us with her own summary sheet of some info...we showed it to the Prof and he said whats this?..and why are you using it to guide urself's'?...we said "because the Tut leader gave it to us"....Prof says "so what, doesn't mean you just walk off with that, you have to make your own resource and approach the material differently etc"..........long enough example...but point im trying to make......the major and important brake component of the bike, I didn't want to post one time, get an answer and vwallah done with....nope, sorry, I had to ask some more questions and learn......and much thanks to those who helped in my brake problem
2nd riding season, and realized tires and brakes REALLY important in terms of maintenance!