Author Topic: Caliper Piston...Replace ? Pic  (Read 8768 times)

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Offline Bill K

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Caliper Piston...Replace ? Pic
« on: January 03, 2009, 10:43:56 AM »
Brakes squeeking...going through caliper clean, new seal. Should I replace this piston ? Pits to bad ? Thanks

Offline bert96

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Re: Caliper Piston...Replace ? Pic
« Reply #1 on: January 03, 2009, 10:50:54 AM »

 Replace it with phenolic piston.
QA50 1969,ST-90 1974,mb5 1982,rz350 1983,shadow 1100 1985,vf1000f 1985,BMW K1 1990,shadow tourer 1100 2001,vfr 750 1994,vtr250 199?

Offline Kemp

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Re: Caliper Piston...Replace ? Pic
« Reply #2 on: January 03, 2009, 10:56:41 AM »
Pray tell, what is a phenolic piston, why is it better and who would carry this item?

Offline Bill K

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Re: Caliper Piston...Replace ? Pic
« Reply #3 on: January 03, 2009, 10:59:49 AM »
 yea, go ahead with it..      NICE AVATAR !

Offline bert96

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Re: Caliper Piston...Replace ? Pic
« Reply #4 on: January 03, 2009, 11:07:41 AM »

 I bought two for my bike from Kevin Hunter.They are made by Ford for their Lincoln.They will never rust(it's not plastic but it's look like it) much lighter than the OEM piston.
QA50 1969,ST-90 1974,mb5 1982,rz350 1983,shadow 1100 1985,vf1000f 1985,BMW K1 1990,shadow tourer 1100 2001,vfr 750 1994,vtr250 199?

Offline bert96

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Re: Caliper Piston...Replace ? Pic
« Reply #5 on: January 03, 2009, 11:09:31 AM »

I still have his email,pm me if you want more information from him.
QA50 1969,ST-90 1974,mb5 1982,rz350 1983,shadow 1100 1985,vf1000f 1985,BMW K1 1990,shadow tourer 1100 2001,vfr 750 1994,vtr250 199?

Offline TwoTired

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Re: Caliper Piston...Replace ? Pic
« Reply #6 on: January 03, 2009, 11:14:25 AM »
That piston is reusable.


Sealing isn't and issue.  However, when the pits do eventually get deep enough, they interfere with piston retraction and cause brake drag.  I doubt yours is to that point though.

Make sure you use the correct chemicals and lubes for reassembly, and it should serve another 10 years.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
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Offline Bill K

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Re: Caliper Piston...Replace ? Pic
« Reply #7 on: January 03, 2009, 11:33:26 AM »
 Thanks TT, thats what I wanted to hear ! Silicon grease right ? One of my manuals says no "brake grease". Sorry, I read this in detail in a previous thread, been searchn, cant find it.

Offline TwoTired

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Re: Caliper Piston...Replace ? Pic
« Reply #8 on: January 03, 2009, 11:59:08 AM »
I wrote a caliper rebuild walk through many years ago.  This was placed in the brake FAQ.

The brake assembly lube is kind of hard to find these days, as the popularity of reconditioning brake components has given way to the rebuilt offerings in the automotive arena.

Beware, the silicon grease offering, too.  There should be NO petroleum content in the silicone grease.  Dow Corning High vacuum grease is the only offering I know about that is pure silicone grease and won't melt or creep into the brake pads.    It's only function is to keep water from contacting the metal bits behind the brake pucks.  Since it doesn't mix with anything, it is ideally suited for this task, and a thin coating is all that is needed to keep water and other contaminants from corroding those parts.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
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Offline Artfrombama

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Re: Caliper Piston...Replace ? Pic
« Reply #9 on: January 03, 2009, 01:54:27 PM »
Call me a redneck/shadetree/backyard engineer but my piston was pitted much worse than that.
I bead-blasted the pits then filled them with JB Weld and sanded smooth.

No leaks so far.
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Offline Ace

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Re: Caliper Piston...Replace ? Pic
« Reply #10 on: January 03, 2009, 02:15:46 PM »
I filled my pits up with epoxy and sanded it smooth.  Works well, no leaks or dragging.
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Offline Bill K

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Re: Caliper Piston...Replace ? Pic
« Reply #11 on: January 03, 2009, 04:35:04 PM »
 If the pits were any worse, Id definitely go with the fill and sand idea. I'm all about the fix it, use it and save a buck !

Offline bert96

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Re: Caliper Piston...Replace ? Pic
« Reply #12 on: January 04, 2009, 08:27:31 AM »

 I refuse to have parts like that on bike,for me it's always an excuse to change parts, and in the same time update with better quality ::)
QA50 1969,ST-90 1974,mb5 1982,rz350 1983,shadow 1100 1985,vf1000f 1985,BMW K1 1990,shadow tourer 1100 2001,vfr 750 1994,vtr250 199?

Offline voxonda

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Re: Caliper Piston...Replace ? Pic
« Reply #13 on: January 04, 2009, 08:32:07 AM »
If ever there comes a time I had to use these kind of brakeparts, I quit riding. We are talking brakes(!) here, never ever save a buck here!
Better sorry for failing then for the lack of trying.

Offline bert96

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Re: Caliper Piston...Replace ? Pic
« Reply #14 on: January 04, 2009, 08:58:34 AM »

 I should say  upgrade and not update! ;)
QA50 1969,ST-90 1974,mb5 1982,rz350 1983,shadow 1100 1985,vf1000f 1985,BMW K1 1990,shadow tourer 1100 2001,vfr 750 1994,vtr250 199?

Offline HavocTurbo

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Re: Caliper Piston...Replace ? Pic
« Reply #15 on: January 04, 2009, 09:00:21 AM »
I don't think it's a question of saving a buck here will DECREASE the quality of braking. I think it's a question of...

Do I want to go out and spend $$ in this economic climate? Or can I recondition my existing parts for less than the cost of a new one and still be able to perform at stock levels?

That would be how I would look at it.
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Offline Artfrombama

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Re: Caliper Piston...Replace ? Pic
« Reply #16 on: January 04, 2009, 09:26:32 AM »
I don't think it's a question of saving a buck here will DECREASE the quality of braking. I think it's a question of...

Do I want to go out and spend $$ in this economic climate? Or can I recondition my existing parts for less than the cost of a new one and still be able to perform at stock levels?

That would be how I would look at it.
What was my determining factor, did I want to wait another 1-1.5 weeks for a replacement or do a quick repair and ride?
« Last Edit: January 04, 2009, 01:44:51 PM by Artfrombama »
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Offline TwoTired

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Re: Caliper Piston...Replace ? Pic
« Reply #17 on: January 04, 2009, 10:42:57 AM »
On my first front caliper rebuild, I took a piston in worse shape than pictured to my Honda dealer.  After the counterman told me the price of a new one, and watched all the blood drain from my face, he called the mechanic to the parts counter to have a look.  One glance at it, and he said. "It looks brand new, reuse it!"  (Lawyers might drool over potential liability suits.  But, I think all they would gain is a dry mouth.)

Anyway, I did reuse it, and that was well over 15 years ago.  The front brake caliper has never leaked, and after I switched to S.S. braided hydraulic lines, will squall the front tire if you squeeze the brake lever hard enough.  It's a 550 with a big Jammer fairing on it.

I can't see any compromise in brake performance by reusing the old caliper piston in the condition posted.

Having said that.  I already bought 5 of those Phenolic pistons from Kevin for eventual use in my fleet, as I have a couple pistons corroded beyond service life (determined by the amount of seal distortion in large corrosion pits).  The bad ones don't leak, but they do drag because they won't retract properly. I haven't actually need to install any Phenolics yet.  But, I see no reason why they wouldn't give a lasting benefit due to their anti corrosion characteristics. And, they were cheaper than any other replacement I could find.  I do NOT expect them to improve brake performance.  Only brake durability with time.  So, they may be better brakes in the long term, but probably not in the next 5-10 years.

The high brow argument of spending max money on brakes because it is "safer", is a hollow argument without any reasonable fact to back it up, in this case.  Spend your money where you wish, if it makes you feel good.  If laying a guilt trip on someone else is your thing, I don't see a real benefit to either giver or recipient.

If spending money is the only criteria, then those SUV drivers must be better than the econo drivers in commute traffic too, right?  Perhaps that's an ideal shared by Harley drivers?  More money = a better bike?

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
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Offline HavocTurbo

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Re: Caliper Piston...Replace ? Pic
« Reply #18 on: January 04, 2009, 12:30:57 PM »

If spending money is the only criteria, then those SUV drivers must be better than the econo drivers in commute traffic too, right?  Perhaps that's an ideal shared by Harley drivers?  More money = a better bike?

Cheers,

My stepfather just bout an 08 Ultra Classic II.... Says anything with the bar and shield on it is an extra Hundred Dollars = HD

Good thing he has more money than god. I'll stick to my "off brands" thank you.  ;D
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Offline voxonda

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Re: Caliper Piston...Replace ? Pic
« Reply #19 on: January 04, 2009, 01:04:23 PM »
...
1)I can't see any compromise in brake performance by reusing the old caliper piston in the condition posted.
...
2)The high brow argument of spending max money on brakes because it is "safer", is a hollow argument without any reasonable fact to back it up, in this case.  Spend your money where you wish, if it makes you feel good.
3)If laying a guilt trip on someone else is your thing, I don't see a real benefit to either giver or recipient.


@1) I(!) think that is one of the few things that makes sence.
@2) Who mentioned that, and where?
@3) What the ... >:( are you suggesting?
Better sorry for failing then for the lack of trying.

Offline HavocTurbo

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Re: Caliper Piston...Replace ? Pic
« Reply #20 on: January 04, 2009, 01:07:40 PM »
LOL and it starts.....  ;D
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Offline Steve F

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Re: Caliper Piston...Replace ? Pic
« Reply #21 on: January 04, 2009, 01:50:53 PM »
I've used pistons in worse shape than that one in the photo and have not had a single problem.  The main point is to be sure that the seal will cover any pits, or in other words the pits won't span the width of the seal, and leak past.
What I see in the last few posts are arguments going toward the idea that the brakes are your life, which in fact they are, and that there is "no way you should skimp" on replacement parts.  My take on all of this is if you want to spend, spend, spend, then by all means, spend away.  I also see the points that are "not everything NEEDS" to be factory perfect to perform and BE SAFE as the brand new factory bike.  For instance, the things that you shouldn't compromise would be the brake lines, which if they were to fail, that would be considered a catrostophic failure, and something that could put your life in immediate danger.  A pitted piston, worst case scenario would be a leak of fluid, and most likely would be noticed if the owner would clean and inspect his bike on a regular interval.  There ARE priorities, and there are NON-priorities, and a pitted piston just doesn't make the priority list.

Offline TwoTired

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Re: Caliper Piston...Replace ? Pic
« Reply #22 on: January 04, 2009, 01:56:17 PM »
LOL and it starts.....  ;D
...and ends ... gets recycled... ad nauseam. 

 ::)

 ;D ;D
Lloyd... (SOHC4 #11 Original Mail List)
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Offline Artfrombama

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Re: Caliper Piston...Replace ? Pic
« Reply #23 on: January 04, 2009, 01:57:45 PM »
Just being the devil's advocate here, not trying to get in anybody's #$%*; ;)

But when does being a mechanic end and being a parts replacement tech begin?

When I see a drop of brake fluid hanging from the caliper, I'll order the new piston and replacement seal.
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Offline voxonda

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Re: Caliper Piston...Replace ? Pic
« Reply #24 on: January 04, 2009, 02:08:48 PM »
...and ends. 

[/quote]

Think that is the best thing to do.

Better sorry for failing then for the lack of trying.