Rear Brake paed disintegrated

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CJDMOON

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My wife and I had ridden about 100 mile with no problems. We stopped for lunch and were going about 80 on a California Freeway for 20 miles when I felt the bike lose some power. My bike was smoking as the rear brake pad on the right side was in pieces and wedged in the smoking disc. Brake fluid was leaking as well. Luckily I was able to remove the pieces and make it home as the fluid stopped leaking. Is this problem unique. We were lucky because we were about 5 miles from our twisty road turn off. Whew! Should I get replacement parts or change the whole thing? Thanks

 
I think the rear brake lever probably hung up, a pretty common event on this bike. It will cause the rear brake to drag and cause severe overheating. When mine did it it caused the rotor to warp so I had to replace it. Since then it's an annual drill to take it apart and lube it.

 
I would replace the caliper seals as well. That much heat probably damaged the seal.

Just to recap the parts checklist...

Brake pads

Brake rotor

Rotor screws (they are not typically re-useable)

Caliper Seals

The rotor screws must be heated to be removed. They are installed with Red Loctite. Be sure to use Red Loctite when you replace them.

It goes without saying, but a complete flush of the rear brake system is required. And of course, you'll need to remove, clean and re-grease the brake pedal/arm. That's where all your problems began.

:(

 
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I would replace the caliper seals as well. That much heat probably damaged the seal.
Just to recap the parts checklist...

Brake pads

Brake rotor

Rotor screws (they are not typically re-useable)

Caliper Seals

The rotor screws must be heated to be removed. They are installed with Red Loctite. Be sure to use Red Loctite when you replace them.

It goes without saying, but a complete flush of the rear brake system is required. And of course, you'll need to remove, clean and re-grease the brake pedal/arm. That's where all your problems began.

:(
Thank you for the great advice. What pads do you recommend?

Sorry I couldn't spell pads!

The system was so hot that initially I had very little front brake, is that because the system is linked? The strange thing is that I had hardly touched the rear brake as I was only on the Freeways, must of used it "Just Enough" lol

 
The rear and front brakes share a lot of common hardware, such as the ABS pump and one front caliper. Boiling the rear brake fluid probably did some serious heat damage to the front fluid as well. I'd definitely recommend a fluid flush of both systems.

I'm an EBC HH Sintered pad man myself. The EBC pads wear faster than the OEM, but they seem to do less rotor damage (because the pad wears instead of the rotor), and the best thing about EBC HH for me is that they don't "grab" on the initial contact as harsh as OEM. It's a smoother braking action IMO.

When it comes to brakes, I take NO chances. I'd replace anything rubber that was directly exposed to boiling fluid, and I would inspect every single piece of both systems carefully. The FJR's 100 mph to zero in roughly 4.3 seconds, is the single best statistic it possesses.

You can only go as fast as you can stop. Keep those brakes pristine.

 
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The rear and front brakes share a lot of common hardware, such as the ABS pump and one front caliper. Boiling the rear brake fluid probably did some serious heat damage to the front fluid as well. I'd definitely recommend a fluid flush of both systems.
I'm an EBC HH Sintered pad man myself. The EBC pads wear faster than the OEM, but they seem to do less rotor damage (because the pad wears instead of the rotor), and the best thing about EBC HH for me is that they don't "grab" on the initial contact as harsh as OEM. It's a smoother braking action IMO.

When it comes to brakes, I take NO chances. I'd replace anything rubber that was directly exposed to boiling fluid, and I would inspect every single piece of both systems carefully. The FJR's 100 mph to zero in roughly 4.3 seconds, is the single best statistic it possesses.

You can only go as fast as you can stop. Keep those brakes pristine.
Would an EBC be a good rotor choice in your opinion? Thanks again !

 
Would an EBC be a good rotor choice in your opinion? Thanks again !
I can't say. I have two sets of wheels for my '07, with over 100,000 miles on the pair. Haven't replaced a rotor on them yet. Which is another reason I speak so highly of the EBC pads.

I've done rotors on other people's bikes, but not my own FJRs. Unless there is a HUGE price break for aftermarket, I'd stick with OEM. IMO, it's a lot of labor involved to be experimenting.

Somebody like Niehart who likes purdy stuff on his bikes, probably is much better to ask about aftermarket rotors. Heck, he may even have a stock rotor for you.

 
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I have Galfer Wave Rotors on my 06. Like the looks but don't really think they helped with braking. I bought the rotors at the international bike show.
You can see them here:

https://www.bikeeffects.com/proddetail.asp?prod=DF000%2D04

I still have the stock rotors but I going to keep them.

Thanks I was considering the Galfer rotors. So you helped me make my decision to go slightly cheaper,EBC. I see the Galfer's are pricey on the front but if they worked better I would save up for them eventually. Hope for an update. Thanks

 
I agree with the advice that brakes are critical and you should take no chances.

I went through a similar problem on a non-ABS Yamaha, and in the end it turned out that the cause was a small pressure relief valve in the bottom of the front brake's master cylinder and the internal pathways that appear to have gotten blocked (through neglect of the previous owner). I tried cleaning and changing fluid, etc. After two failed attempts to get the problem totally solved by rebuilding parts, I took it to the dealer, who also cleaned and replaced fluid. Seemed to be fixed for about a day. Then I was right back with the same problem. Tired of the aggravation, I replaced the caliper, pads, hose, and master cylinder. After that it worked as it had when new (as it should since all the parts in the front hydraulic circuit were now new). Lucky for me it hadn't been asked to do enough to warp the disk, or that would have had to go too.

Be careful, especially when you're riding for two.

 
On a post back in August I described how my brake pads had disintegrated. Now after working on my other bikes I have gotten back to the FJR. It appears that the parts melted to the hard parts. I have pictures if I only understood how to show them! Question, should I file off the melted metal or go to a new braking system. I already have the pads, piston and new rotor? Thanks

 
Parts melted to hard parts isn't really descriptive. Which parts to which parts, and what's a hard part? :)

The forum doesn't host pics for itself, you have to set up on a site like Photobucket and link to the pics here. Photobucket is tremendously easy to use.

 
I'm real curious here. Never seen brakes or metal melt on a street bike from braking. Please post pix and go into some extreme detail for us.

Here is a pic this is not lower where shiny but higher
BeyondtheRotors002.jpg


https://i749.photobucket.com/albums/xx133/C...heRotors001.jpg
BeyondtheRotors001.jpg
BeyondtheRotors2002.jpg
BeyondtheRotors2001.jpg


I t looks like some of my bad welds back in the day! Thanks for the help with the pics!

 
Looks like when Skooterg forgot to torque his bolts and lost them as he was going down the road. He figured out the caliper likes to migrate to the forks and rotor then likes to dig into the caliper. You or the previous owner end up investing in a second pair of missing caliper bolts in the past?

 
Looks like when Skooterg forgot to torque his bolts and lost them as he was going down the road. He figured out the caliper likes to migrate to the forks and rotor then likes to dig into the caliper. You or the previous owner end up investing in a second pair of missing caliper bolts in the past?

Everything is or was original. A good rider would have stopped with the loss of power instead of more throttle. I appreciate all the help and advise in it not happening again.

 
That looks like a caliper that's been used with no pads in it. The "melted" gunk on the one side is rotor metal, I'm betting. The scrape marks on the piston are another clue.

Another member reported the pads falling out of his rear caliper some time ago, but I can't find that thread. I think the consensus was that one of the ears had broken on the backplate of a pad, giving it enough slop to slip out of the caliper. Once that one went, the other could rattle out by itslef within a few minutes of riding.

 
That looks like a caliper that's been used with no pads in it. The "melted" gunk on the one side is rotor metal, I'm betting. The scrape marks on the piston are another clue.
Another member reported the pads falling out of his rear caliper some time ago, but I can't find that thread. I think the consensus was that one of the ears had broken on the backplate of a pad, giving it enough slop to slip out of the caliper. Once that one went, the other could rattle out by itslef within a few minutes of riding.
Gunny Now that I see it, your caliper and piston were your brake pads. What happened to the pads?
Scenario one: More than likely the pins/clips that hold the pads on fell out, maybe the little clip was never reinstalled? Could happen but once the pads fell out or one at first you should have really had to pump a few times the lever to make up for the amount of travel the piston would travel to make up for the missing pad.

Scenario two: Never changed the pads, got down to metal and then went away, highly unlikely though, scenario one make more sense to me.

Are you the original owner? Who took off the rear wheel last, or did brakes or caliper stuff, maybe even swing arm?

Although our very own SFD (figure it out) had the stealer install his pads backwards, metal to rotor, pad to piston and caliper. Amazingly, he had no damage to rotors etc. He got new pads, finished.

 
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BTW, that caliper cylinder needs to be thoroughly cleaned, and new seals installed, before reassembly.

I don't know if I'd go with new piston, seals, pads, and clips, or just chunk it all and do a whole caliper assembly.

Rotor needs to be measured every which way from Sunday, too! Thickness, runout, warpage . . . . .

I posted this pic in that other thread I couldn't find a while ago. . . This is the back side of the rear caliper, showing the clips (seen end-on) that should be at the ends of the pads. Without those, the pads have an awful lot of rattle/wiggle room, maybe enough to eventually eject one. If one goes, the other won't be there very long, as the caliper will have lots of room to slide back and forth.

rearbrake.jpg


EDIT:::: It occurs to me, now some 180 minutes later, that skipping one little step in pad replacement could lead to the disappearing pad scenario: Forgetting to pump the pedal to squeeze the new pads against the rotor. With the piston pushed all the way in, new pads installed, caliper reinstalled, all seems well, except the pad may still have room to slide out under vibration if the piston hasn't ben pushed out by hydraulic pressure to remove the installation slack.

 
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