Deep Clean YOUR Calipers!!

[Kruse08]

I just wanted to inform everyone how vital it is to deep clean your calipers every so often. The wiki page has a DIY on this and it really is not difficult. The reason I am posting this is because the previous owner of my bike only did basic maintenance and when I say basic I mean basic. My bike only has 13k miles on it but the pistons in side the calipers are rusty and pitted. If they were not pitted I would be able to sand them down and reuse them. So the rebuild is expensive if you have to go through with replacing pistons. You can avoid all of this if you deep clean and lubricate every once in awhile. I want to thank Crazymadbastard for having low mileage replacement calipers that I was able to buy to replace mine. I will be deep cleaning my old ones just to have an extra set lying around for parts or if someone is in need of a set (per the warning that the pistons do have some pitting). So please deep clean your calipers as your brakes are vital to your safety and others. Do not neglect them as the previous owner did. Also, there were freaking cobwebs within the calipers, cobwebs!

Picture is large due to Photobucket running into an error when I tried to re-size.

[agentbad]

I put some permatex on my piston after the last rebuild. Seems to be keeping things moving smoothly.

[adouglas]

Just popped over to the wiki and didn't see anything that looked like caliper maintenance. Gotta link?

[Ghostt]

Something like this look familiar,

For those of you whom are scratching their heads, here you go,*


Front Caliper Service (also rear as well)

Many folks have posted here with a Varity of front brake problems.*

*Many of which are attributable to the lack of proper maintenance.

*Here’s how you can always have a brake like when your bike was new.

A short list of the problems and the causes.

Soft lever or lever goes to the bar.

The usual cause is the pistons are pushed too far back into the caliper by a flexing a warped, coned, disc.*

*Using up too much piston travel before the disc is pinched.

Juddering in sync with wheel rotation.

The disc is worn, and its thickness varies. *This causes the caliper to “sink” into the thin part and when the thick part comes around, it gets wedged into a smaller space causing a tightening of the brake. Then the tight spot passes through and it like the brake is released. Then repeat, repeat.

Cupped, coned, or warped disc.

Unfortunately this is a common problem with EX’s the cause is the disc is stretched in the center due to being rigidly bolted to the wheel. *The huge force of braking is transmitted to the wheel through the webbed center of the disc which gets stretched and becomes larger than the space it occupies in the center of the disc. This causes the center to push to the side trying to find room for itself.*

*Resulting is a cone shaped disc.

Soft lever 2

The caliper has pistons only on one side, so as the pads wear the caliper must shift sideways apply even pressure on both sides of the disc.*

*To allow this the caliper floats on two pins. *If these pins get dry (no grease) dirty or bent. The caliper won’t center itself and bends the disc to wherever it is.

*This take up lever travel and when released pushes the pistons further back than necessary.

**If not fixed will eventually destroy the disc (warp it).


Ok how to prevent all of the above.

When new pad time comes around, resist the temptation to just pop in new one and go.

*Every time you must do these things.

Remove caliper disassemble and clean it.

Clean and re grease the sliding pins.

Polish the caliper pistons to remove dirt. If you just push the pistons back into the caliper leaks will result. Or binding.

Tools required:*
12 mm socket
8mm open end wrench
3” or bigger C clamp
a supply of new bake fluid.*
wire brush and or steel wool.

Remove the caliper from the fork leg but leave the brake line on.

Remove the old pads and the mounting frame (the sliding pins)

Remove the cover from the Master Cylinder on the Handel bar.

Attach the C clamp to one of the pistons but don’t squeeze it. *Pump the lever on the bar slowly to push out the other piston almost all the way. *Put the C clamp on that piston and push out the other one.

Remove both pistons by hand.

Remove all the rubber part from the caliper, the seals are in the grooves in the caliper and dull pointed thingy will get them out easy.

Disconnect the caliper from the brake line.

Soak all the rubber parts in new clean brake fluid * ONLY!!!!! * Rub them with you fingers till as clean as new.

The caliper can be cleaned with a wire brush or even a Moto tool for the internal grooves, NOW’s the time to paint it if you wish.

Polish the pistons till they are smooth and shinny. They are chrome plated. If any of the plating is chipped or damaged below the dust cap groove. *Replace it.

The master cylinder is the subject of another write up and we’ll assume it in good working order here.

If you suspect your disc is bad, your bets bet is to replace it with an after market one fro EBC or Galpher.

*Don’t remove the disc unless you intend to replace it. *It will assume a new shape if it is * stressed and will not be flat again. You can try to check its condition by placing a straight edge across the face of the pad swept area looking for any distortion.

Re assembly

Take the nice clean rubber seals and install them into the caliper then the Dust covers.
Wet all the rubber with new clean brake fluid and partially fill the caliper with new fluid.

Push the pistons though the dust seals and into the caliper body until the dust covers snap into the grooves.

Fill the MC with new fluid and pump the lever while holding the Line above the MC till clean fluid flows.

Connect the line to the caliper while holding it above the MC.

Pump the lever with the bleeder valve open till fluid flow from the bleeder.

**Hold the caliper so that the bleeder is the highest point.

Close the bleeder and pump more fluid into the caliper but don’t push the pistons all the way out.

Then squeeze the pistons all the way back in and install the new pads.

Re grease the slider pins and assemble the dust seals and re mount the caliper on the forks but leave the bolts loose.

Now clamp the caliper to the disc with the brake lever.

Look at the space between the fork lugs and the caliper, clamp and release a few times as you tighten the bolts by hand. It one lug touches much before the other the odds are you mounting bracket is bent. You can straighten it.*

*After you get it the best you can. Some shim washers made from alum can stock can be fitted to the loose side.*

** *What we are doing here is trying to minimize the bedd in time and gets the best pad life.


Ok with everything tight you should be through, Notice we don’t need to bleed the brakes, but if you screwed up in any of the above steps, you might do that here.

Be careful to Bedd in the new pads gently.

**Too much pressure too soon will burn the pad material as only a small area will be gripping at first. You also won’t have full braking power till the pads are fully familiar with the disc

[Motofool]

Originally Posted by Ghostt

Something like this look familiar,

How do you use to "clean and re grease the sliding pins"?

Do you replace the internal seals every two years as recommended by Kawasaki?
Any particular installation orientation for those seals?

[Kruse08]

Here are some links:

http://faq.ninja250.org/wiki/Brake_caliper_rebuild
http://faq.ninja250.org/wiki/How_do_..._brake_pads%3F

Just look through that website and it is full of information you need.

[Qomomoko]

pitting...

mine have like external deposits, like rust... I will try and sand...

is pitting the opposite of external deposits and more like little dents??

I'll post pics when get home...

[Motofool]

Originally Posted by Qomomoko

pitting...

mine have like external deposits, like rust... I will try and sand...

is pitting the opposite of external deposits and more like little dents??

I'll post pics when get home...

http://en.wikipedia.org/wiki/Pitting_corrosion

[Qomomoko]

Originally Posted by Motofool

http://en.wikipedia.org/wiki/Pitting_corrosion

sweet, mine are the little mountain like, so I should be able to sand them off

[Ghostt]

All the answers you seek are in my write-up, it's very clear about condition of the pistons.

Ask yourselves what your your safety and possibly life is worth? Mine is worth more than a new piston and/or seals.

Brakes are one of the things you NEVER skimp on.

[Kruse08]

Do you think the pistons can be saved within the calipers I have?

[Ghostt]

Originally Posted by Kruse08

Do you think the pistons can be saved within the calipers I have?

Once again follow my guide and see how they clean up.

In the end it's your judgement call.

[CZroe]

Mine looked worse than the OP the first time I ever replaced the pads. The DIYs only said to use brake cleaner, which did absolutely nothing. Why would I have to rebuild them on the first brake job? What can I do to keep it from happening again? Is that what hi-temp brake lube is for?

[Ghostt]

Originally Posted by CZroe

Mine looked worse than the OP the first time I ever replaced the pads. The DIYs only said to use brake cleaner, which did absolutely nothing. Why would I have to rebuild them on the first brake job? What can I do to keep it from happening again? Is that what hi-temp brake lube is for?

Hi temperature lube is for the slider pins only.


Okay one more time,

For those of you whom are scratching their heads, here you go,*


Front Caliper Service (also rear as well)

Many folks have posted here with a Varity of front brake problems.

*Many of which are attributable to the lack of proper maintenance.

*Here’s how you can always have a brake like when your bike was new.

A short list of the problems and the causes.

Soft lever or lever goes to the bar.

The usual cause is the pistons are pushed too far back into the caliper by a flexing a warped, coned, disc.

*Using up too much piston travel before the disc is pinched.

Juddering in sync with wheel rotation.

The disc is worn, and its thickness varies. *This causes the caliper to “sink” into the thin part and when the thick part comes around, it gets wedged into a smaller space causing a tightening of the brake. Then the tight spot passes through and it like the brake is released. Then repeat, repeat.

Cupped, coned, or warped disc.

Unfortunately this is a common problem with EX’s the cause is the disc is stretched in the center due to being rigidly bolted to the wheel. *The huge force of braking is transmitted to the wheel through the webbed center of the disc which gets stretched and becomes larger than the space it occupies in the center of the disc. This causes the center to push to the side trying to find room for itself.

*Resulting is a cone shaped disc.

Soft lever 2

The caliper has pistons only on one side, so as the pads wear the caliper must shift sideways apply even pressure on both sides of the disc.

*To allow this the caliper floats on two pins. *If these pins get dry (no grease) dirty or bent. The caliper won’t center itself and bends the disc to wherever it is.

This take up lever travel and when released pushes the pistons further back than necessary.

*If not fixed will eventually destroy the disc (warp it).


Ok how to prevent all of the above.

When new pad time comes around, resist the temptation to just pop in new one and go.

*Every time you must do these things.

Remove caliper disassemble and clean it.

Clean and re grease the sliding pins.

Polish the caliper pistons to remove dirt. If you just push the pistons back into the caliper leaks will result. Or binding.

Tools required:
12 mm socket
8mm open end wrench
3” or bigger C clamp
a supply of new bake fluid.
wire brush and or steel wool.

Remove the caliper from the fork leg but leave the brake line on.

Remove the old pads and the mounting frame (the sliding pins)

Remove the cover from the Master Cylinder on the Handel bar.

Attach the C clamp to one of the pistons but don’t squeeze it. *Pump the lever on the bar slowly to push out the other piston almost all the way. *Put the C clamp on that piston and push out the other one.

Remove both pistons by hand.

Remove all the rubber part from the caliper, the seals are in the grooves in the caliper and dull pointed thingy will get them out easy.

Disconnect the caliper from the brake line.

Soak all the rubber parts in new clean brake fluid * ONLY!!!!! * Rub them with you fingers till as clean as new.

The caliper can be cleaned with a wire brush or even a Moto tool for the internal grooves, NOW’s the time to paint it if you wish.

Polish the pistons till they are smooth and shinny. They are chrome plated. If any of the plating is chipped or damaged below the dust cap groove. *Replace it.

The master cylinder is the subject of another write up and we’ll assume it in good working order here.

If you suspect your disc is bad, your bets bet is to replace it with an after market one fro EBC or Galpher.

*Don’t remove the disc unless you intend to replace it. *It will assume a new shape if it is * stressed and will not be flat again. You can try to check its condition by placing a straight edge across the face of the pad swept area looking for any distortion.

Re assembly

Take the nice clean rubber seals and install them into the caliper then the Dust covers.
Wet all the rubber with new clean brake fluid and partially fill the caliper with new fluid.

Push the pistons though the dust seals and into the caliper body until the dust covers snap into the grooves.

Fill the MC with new fluid and pump the lever while holding the Line above the MC till clean fluid flows.

Connect the line to the caliper while holding it above the MC.

Pump the lever with the bleeder valve open till fluid flow from the bleeder.

*Hold the caliper so that the bleeder is the highest point.

Close the bleeder and pump more fluid into the caliper but don’t push the pistons all the way out.

Then squeeze the pistons all the way back in and install the new pads.

Re grease the slider pins and assemble the dust seals and re mount the caliper on the forks but leave the bolts loose.

Now clamp the caliper to the disc with the brake lever.

Look at the space between the fork lugs and the caliper, clamp and release a few times as you tighten the bolts by hand. It one lug touches much before the other the odds are you mounting bracket is bent. You can straighten it.

*After you get it the best you can. Some shim washers made from alum can stock can be fitted to the loose side.*

** *What we are doing here is trying to minimize the bedd in time and gets the best pad life.


Ok with everything tight you should be through, Notice we don’t need to bleed the brakes, but if you screwed up in any of the above steps, you might do that here.

Be careful to Bedd in the new pads gently.

*Too much pressure too soon will burn the pad material as only a small area will be gripping at first. You also won’t have full braking power till the pads are fully familiar with the disc

[rubber side down]

A good cleaning once and awhile never hurts the pistons. Most of the time that I have seen stuck pistons in the caliper has been due to leaking fork seal/s, more so that brake dust or anything else. The oil catches all the dust and dirt and the piston makes a nice collecting area.

[Ghostt]

Calipers should be serviced every time when changing pad, at the very least.

[CZroe]

Originally Posted by Ghostt

Hi temperature lube is for the slider pins only.


Okay one more time,

Thanks, but I don't see anything there that tells me what to do between services if it's already too far gone when it's time to be serviced. Even if I change my pads earlier just to service the caliper/pistons, it just says "polish." With what? Rubbing compound? Chrome polish? A drill attachment? Is there anything protective I can add between services to keep it from accumulating deposits and getting pitted?

Originally Posted by rubber side down

A good cleaning once and awhile never hurts the pistons. Most of the time that I have seen stuck pistons in the caliper has been due to leaking fork seal/s, more so that brake dust or anything else. The oil catches all the dust and dirt and the piston makes a nice collecting area.

A good cleaning with what? Brake cleaner did absolutely nothing for me. My pistons were still covered with rocky crap that I could not wipe off after I used an entire can.

Originally Posted by Ghostt

Calipers should be serviced every time when changing pad, at the very least.

That's what I'm saying: They were already trashed when it came time to service them, so what can I do before then? How do I keep my pistons from getting pitted and corroded between brake pad changes?

[crazymadbastard]

Originally Posted by CZroe

A good cleaning with what? Brake cleaner did absolutely nothing for me. My pistons were still covered with rocky crap that I could not wipe off after I used an entire can.

Use a brass brush, not steel as it can damage the finish.

[Somchai]

I remember times when even after 200000 km there was absolute NO service for the brake calipers necessary...

[Qomomoko]

Originally Posted by CZroe

Thanks, but I don't see anything there that tells me what to do between services if it's already too far gone when it's time to be serviced. Even if I change my pads earlier just to service the caliper/pistons, it just says "polish." With what? Rubbing compound? Chrome polish? A drill attachment? Is there anything protective I can add between services to keep it from accumulating deposits and getting pitted?



A good cleaning with what? Brake cleaner did absolutely nothing for me. My pistons were still covered with rocky crap that I could not wipe off after I used an entire can.



That's what I'm saying: They were already trashed when it came time to service them, so what can I do before then? How do I keep my pistons from getting pitted and corroded between brake pad changes?

my plan is to keep try and keep my bike inside...
also to get stainless steel pistons...

but good questions you have.

[CZroe]

Now that I think about it, a dealer installed the first set of pads so it had to be the second set of pads that I first installed myself (that's when I discovered the poor condition of the pistons).

My bike was a daily driver for 3 years (didn't own a car) and was almost always outside and uncovered, rain or shine. I expected it to take it as well as a car treated the same way. The only additional precautions for rain I recall from the manual were to clean and lube the chain after every rain ride and to re-oil the air cleaner element after cleaning with solvent. As a result, I did this more frequently than most, but at least it was San Diego so it didn't rain very often.

Can I dip a toothbrush in brake fluid and brush the exposed part of the pistons every now and then? If it is safe to put the same hi-temp grease on them as the sliding pins, would that at least prevent dust and stuff from caking/solidifying on the pistons?

[Ghostt]

Calipers get dirty, it's a fact of life.

The only way to keep them working properly is proper maintenance, service, and knowing when to replace consumable items, like seals part# 43049, A,B,&C, also 49006A just to name a few.

[ninjunk]

One thing that i've noticed with vintage bikes, once the brake pad gets worn down signficantly, there is more exposed piston area (to be hit with corrosion) and more brake dust that is blowing around. This exacerbates the problem. Brake dust is the trifecta of corrosion: sticky, abrasive, and chemically reactive.

For me this is one of those 'do as i say, not as i do' kinda things because i'm super attentive to brakes and brake feel, but when i work on customers' bikes I expect them to be a bit more... how shall i say... oblivious. My own brakes i usually run them down to the metal and I don't rebuld them until something fails.

First of all, water sinks to the bottom of brake juice. That means any moisture that your MC picks up from sitting outside or what have you, ends up pooled in the bottom of your caliper rotting away. This means change your fluid more often if your bike sits outside or if you ride it in the rain. It costs exactly .45 cents to drain and refill your entire front brake system, I do it at least twice a year on a daily driver bike, if not more often. I'm racking up a lot of hard miles on the ninja and will probably at least check fluid condition in the next month or so. The ninja is small enough that you can pop a hose on your lower bleeder, turn the wrench, and pump the lever at the same time. If you know what you're doing you can bleed the entire system in about 10 minutes by just pinching the hose and letting the pressure push past your pinched fingers.

Back to the pads/pistons and 'outside' of the hydraulic system. You can clean the deposits or even rust pits off the pistons with #000 steel wool. They are pretty hard metal and won't scratch. You can also use a fine scotch brite pad, 800 grit sandpaper, etc, but both of those can scratch the metal as they use grit/abrasives which are harder than the steel.

If you get the brake dust deposits off and there are pits underneath, don't freak. You can re-install them with new seals and give it a shot. If they are weeping after that, they are done for, but hey at least ya tried. Just keep an eye on them. In several years of fixing some real basket case motos, i can only think of 1 or 2 times that the pistons were totally un-salvage-able. The combination of neglect and letting the pads wear down too far is the real killer. Most of the time even if they are pitted, it is only in the outer region outside of where the seal seals.



So yeah, to answer the question what to do between brake pad service:

1) Keep dust off the calipers, wheels, etc. (good rule for everything, really)
2) change your brake fluid at the end of every riding season or every 1000-2000 miles depending on how aggressive you are.
3) replace your pads before they are totally 100% gone and the pistons are hanging way out there.

[Qomomoko]

great thread .. great information for such an important topic

[CZroe]

Originally Posted by ninjunk

One thing that i've noticed with vintage bikes, once the brake pad gets worn down signficantly, there is more exposed piston area (to be hit with corrosion) and more brake dust that is blowing around. This exacerbates the problem. Brake dust is the trifecta of corrosion: sticky, abrasive, and chemically reactive.

For me this is one of those 'do as i say, not as i do' kinda things because i'm super attentive to brakes and brake feel, but when i work on customers' bikes I expect them to be a bit more... how shall i say... oblivious. My own brakes i usually run them down to the metal and I don't rebuld them until something fails.

First of all, water sinks to the bottom of brake juice. That means any moisture that your MC picks up from sitting outside or what have you, ends up pooled in the bottom of your caliper rotting away. This means change your fluid more often if your bike sits outside or if you ride it in the rain. It costs exactly .45 cents to drain and refill your entire front brake system, I do it at least twice a year on a daily driver bike, if not more often. I'm racking up a lot of hard miles on the ninja and will probably at least check fluid condition in the next month or so. The ninja is small enough that you can pop a hose on your lower bleeder, turn the wrench, and pump the lever at the same time. If you know what you're doing you can bleed the entire system in about 10 minutes by just pinching the hose and letting the pressure push past your pinched fingers.

Back to the pads/pistons and 'outside' of the hydraulic system. You can clean the deposits or even rust pits off the pistons with #000 steel wool. They are pretty hard metal and won't scratch. You can also use a fine scotch brite pad, 800 grit sandpaper, etc, but both of those can scratch the metal as they use grit/abrasives which are harder than the steel.

If you get the brake dust deposits off and there are pits underneath, don't freak. You can re-install them with new seals and give it a shot. If they are weeping after that, they are done for, but hey at least ya tried. Just keep an eye on them. In several years of fixing some real basket case motos, i can only think of 1 or 2 times that the pistons were totally un-salvage-able. The combination of neglect and letting the pads wear down too far is the real killer. Most of the time even if they are pitted, it is only in the outer region outside of where the seal seals.



So yeah, to answer the question what to do between brake pad service:

1) Keep dust off the calipers, wheels, etc. (good rule for everything, really)
2) change your brake fluid at the end of every riding season or every 1000-2000 miles depending on how aggressive you are.
3) replace your pads before they are totally 100% gone and the pistons are hanging way out there.

Thanks! Lots of great advice. Think I'll pick up some pipe cleaners to deal with the dust every time I lube my chain.