Brake calipers, all years, but especially the early years

Technical information and Q&A applicable to all years and models of Goldwings
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Posts: 8
Joined: Sat Aug 08, 2009 9:30 am
Location: Langley, BC
Motorcycle: Gl1000/75, 78, GL1100/81/82, GL1200/84/86, GL1500/95SE, Valkyrie CT /99, GL1800PS/07

Brake calipers, all years, but especially the early years

Post by StraightWings »

Recently (ie the past three weeks straight) I have been doing a task I have put off for many years: cleaning up, assessing, and preparing a multitude of Goldwing brake calipers for sale, for years from 1975 through 2000. I have an excellent supply of new calipers for Gl1800’s, the rears new, the fronts gone through. I wanted to see how people were proposing to sell them, so did a few hours on various sites.

In reviewing the market place and seeing what is going on out there, and the scary crap being offered by sellers, I thought it would be a good idea to put the resulting considerations on paper.

Notes on buying calipers: Aspects of note:

The pivot pin: is the caliper-thread for the pivot in good condition? It is the number 1 cause of vintage calipers being replaced: cross-threaded and/or stripped threads. Either in the caliper or the stay. Is the pivot sleeve in good order, and the caliper itself where the pivot sleeve rides in good order or worn out? Are ALL threaded points in good condition?
The bores: The bores in a caliper are merely ‘sliders’: lubricated by the brake fluid contained in the piston-chamber. They can be stained without problems. They can NOT be over-bored or worn outside spec, otherwise they will risk binding by various causes.
So: are they good? That means are they pitted, or are they clean? If honed, are they bored out past, or nearly past, Honda specs?
You only get 1 decent hone and 1 “clean-up” (removal of stains), or 2 light-medium hones out of these caliper bores, there’s not a lot of ‘meat’ to work with before you are out of specification.
If not pitted, not bored out, and show stain, that is fine: stains don’t bother the slider-effect if the walls are smooth, and you can and should check for pits under the staining with some fine emery cloth.
Moral of the story: You HAVE TO KNOW that the person you are buying from has disassembled, cleaned the bore and the seal-grooves to verify their condition, and checked the caliper-bore with micrometers, or you could be buying a useless piece even if the exterior looks good.
The seal grooves: inverted ridges: are they clean and true? It is the major reason that caliper get ‘sticky’ and won’t return properly: fluid crystalizes with age under the seals, pushes the seals out into to the piston, restricting and binding it, and often rotting the caliper under the seal, effectively reducing the value of the seal itself to zero. The buildup under the seals invariably happens, and ALWAYS happens with time combined with lack of maintenance.
Are the parts, if any, that come with the calipers in good condition, and what is with the caliper itself. Special attention to:
Pad-pins: they get beat up due to lack of maintenance: frozen to the caliper, and get deformed punching them out with a drift. Depending on the caliper, they can be really hard to source when needed, and are about $12 each (as an example they don’t even show 1982 GL1100 pad-pins on fiches any more, hence, they are unavailable).
Pad springs: usually available, but sometimes they are oddities, and totally unavailable. OFTEN they are bent by piss-poor mechanics installing them badly. Check that they are straight.
Lock-plates for the pins: as with springs, but they are a common part to almost all the early Goldwings, so not a major concern.
The travel area of the piston in a caliper is that portion of the piston that would come in contact with the seals in the caliper. If pistons are lightly pitted in the exposed areas, but not close to the seal-area, they can often be polished to check for ‘hidden’ pitting, and if clean can be saved and reused. Experience: Pistons: out of over 200 calipers disassembled (and that would be well over 300 pistons checked) less than 25 pistons were still good. So: count on replacing the pistons on any caliper that has not been fully disassembled and checked. Mars on pistons areas exposed to moisture and road mung, outside the “travel area”, you can live with, and many bikes on the road have pits on the exposed areas. If the piston has ANY mars or pits in or close to the travel area (that is any section of the piston that might touch the seal with new pads installed and the pistons pushed into the caliper), they are useless. Hence: generally speaking, if the pitting extends more than three to four millimeters from the end of the piston, they are useless.
Brakes pads if included: a good 50% of them with have fork-oil, brake fluid, or other contaminants. If lightly contaminated, they perhaps can be soaked in brake-cleaner and recovered (but never fully recovered, just usable in a pinch). If heavily covered: write them off, it is a waste of time installing them. The point: you may be seeing pads attached to calipers for sale, but are they any good?
Seal Grooves: the reason poorly serviced calipers have dragging brakes and slow-returning pistons is that the groves are filling with crystalized brake fluid and aluminum oxidization buildup. They have to be clean, and you can’t just get in there and grind away: you have to keep those grooves in the configuration that they are in stock: same depth, same width, and must be clean to allow brake fluid to ‘float’ them properly. I have yet to find a knurling tool for cleaning them that doesn’t take out metal unless you are very careful. It comes down to using, typically, hand work using orthodontic dental picks, and I use three different ones to clean the grooves out properly, for every groove. It is a real treat to see the grooves clean in a caliper when disassembled, and it is very rare on older ones to see that, or on any calipers that haven’t seen servicing regularly. They say change your brake fluid every 3 years, and that is a good habit. But, at least every second fluid change, you should remove, disassemble, and clean those calipers, and that is solely to keep the seal-grooves cleaned. More often if your bike is in a damp climate or your are a 'burner' like me: heat-cooling-heat creates condensation).
Really look at and think about the information given by the seller. In 22 years I have yet to spend less than 45 minutes, and it is usually closer to 1.5 hours, on a vintage caliper, or one that has not been serviced within the past 3-4 years: from it being on the bike to being ready for sale. My time is $65 per hour, and as a specialist that is inexpensive.
How can someone sell a purportedly good caliper (if they have checked it properly), for $50, 60, 70? They giving a good caliper away? Or just hoping that it IS a good caliper? This is YOUR ass they are putting brakes under? In a nutshell: they are not interested in really getting into the caliper, because it is too time intensive. For me, I’m 'retired' into nothing but Goldwings, and the work helps winter-boredom, but in no way do I ever recover the time I spend on a caliper together with the caliper itself and the parts contained therein. A bit silly of me, now that I put it in that light. I just hate waste.

If you can answer all three of the above major (first three) questions, the caliper is possibly good. If you, or a responsible and credible seller can’t answer the points in at least the first 4 questions, don’t even think about buying it: you have about a 65% chance of buying a bummer, and about a 95% chance you’ll be doing 2-3 hours work and spending a bit (read as a lot) of money to put them in proper condition to install, IF you have the specialized tools and equipment to do so. A waste of cost + shipping, so beware the advert that says “may need to be rebuilt”: because they don’t know what the condition of the bore, pistons or any other part of the caliper is like. Beware of ANY caliper for sale that doesn’t have a proper assessment of its condition by an experienced individual that would himself risk riding on it.

It breaks down like this, on a two-piston caliper:

Disassembling, cleaning the caliper, checking, cleaning seal-grooves, perhaps a light hone or cleanup by hand with emery cloth: $45-50 in time.
Pistons: average about $35 each = $70 per dual caliper, $40 each for older single-piston systems.
Pad spring: $10
Pad pins: $25
Assembly: 5 minutes for a newer caliper, 10 minutes for a 75 to 77 GL1000: $6-$12
IF the caliper is good, that caliper is worth $85 to $120 as a used NAKED (stripped) caliper, especially for those no longer available at Honda, and that's most of them up to GL1500, and many of those are now in that league.
Pads: $55
Total of the above: Closer to $300 than $250. I sell a good, complete caliper for about $135US. How stupid am I? Duh.

The averages: Just on GL1000, GL1100, GL1200: I parted out over 350 bikes, discarded more than 200 calipers, saved the remainder, that looked good, for review. When dismantled and checked, out of the nearly 650 calipers saved, I found over 250 of them to be useless, and they turned into scrap metal. Many of the others, about 225 over the years, were reviewed and sold upon request, and then many were assessed and listed to keep an inventory available and sold off my site and to current clients.
That left, after 20 years, nearly 175 saved calipers in bins, not reviewed. Out of that 175, 75 were good calipers when ‘opened’. Out of that 75 as above, 17 pistons were usable, the rest were pitted into the travel area. (When the caliper is no good, due to pitted bores or bores past specification, the pistons are invariably no good.)

Regardless: Probabilities based on experience and what I have seen for sale out there: you WILL need to buy need rebuild kits (seals and grommets), almost certainly pistons and perhaps pad-pins, unless specified otherwise by the seller.

NOTE: If the mechanical side of the caliper are good, the esthetics don’t matter a damn: you can repaint more than three calipers with one rattle-can of caliper-paint and 25 cents worth of masking tape. Don’t worry about the outside, concentrate on the mechanical issues.

Much of the above may not apply to calipers after about 1994, as they started using a coating that prevents a lot of bore-pitting (and that isn’t saying it doesn’t happen, but it is lessened): but doesn’t (and can’t) address the piston-rot factor.

[A tip: over the years I have used EZ lube, an extremely fine super-turbine lube I had designed for my national dental-instrument repair entity (Canada Handpiece, a company I built then sold when I ‘retired’ a few years back), by getting access to the exposed portions of the pistons in the fall and again in mid-summer, and putting two to three drops on top of each piston. That weather-proofs them: a couple or three drops of that incredible lubricant is enough to work around each piston without contaminating brake pads, and keeps the exposed portion of the pistons from rusting.]

As a road-racer in my youth I’m what they term a ‘canyon burner’. I cut foot-pegs off my bikes each season in the corners (although with Traxxion Dynamics on my favorite 1800 I’m getting almost two seasons out of a set now). I say that, because in a nutshell: if I sell a caliper, the quality is only and strictly based on the credo: “will this go under my butt to save it going into a hot corner, consistently and reliably?” If the question is not easily and positively answered, that caliper is scrap metal.

I have never, and repeat: never: sold a caliper that I haven’t pulled apart and checked thoroughly. If any single part of the ‘build’ is even remotely questionable, it goes into the garbage bin.

It makes me shudder to think of the ‘crap-attitude’ of people who will put something out for sale that is so critical to the well-being of the buyer as are brake parts, without assuring themselves that with diligence by the buyer to CHECK THE CALIPERS THEMSELVES, the buyer should be safe.

>>>>>>That means that regardless where you buy it, and who from, a used caliper should be dissembled and checked by the buyer themselves.<<<<<<<

[It is easy enough to do: disconnect the easiest-to-bleed line, place the line onto the ‘new’ caliper, and pump out the pistons. Even easier: have an old brake line with a spare banjo-fitting available, disconnect the front master cylinder, place the ‘new’ caliper in-line, and pump the pistons out from there. If you are careful with the bike-brake line when you remove from the caliper, and tie it above the height of the master, you’ll get very little air in the system, and can usually ‘bleed off’ that small amount by gently but rapidly squeezing the brake lever without actually compressing the fluid more than a tiny amount: the air often bleeds back up through the master. I prefer to do it at a wheel, because if you need a new caliper, you always should flush the caliper and the lines anyway.]
{A tip: when pumping out pistons hydraulically, and air will most times not do the job, have a pair of matched wedges with a good long shank: put them in from two directions in the throat of the caliper (in the case of a dual-or-more-piston caliper), and as you pump the pistons out, move the wedges out as well, to keep the pistons coming out equally until you can pull them out by hand (DO NOT USE METAL TOOLS ON PISTONS). You’ll be able to tell when they are out far enough when you see them start to ‘kick’ a bit as they come past the seals} <<<<<<<

It is a 15 minute job to disassemble, check and reassemble a good caliper. It is the cleaning, checking and/or renovation of them that takes the time.

I’m not a mechanic: I’m a multi-tasking multi-trained business-man paper-pusher who has been doing his own wrenching for over 56 years: the period of time I have been riding. There are all kinds of ‘Wingers’ who are excellent ‘wrenches’, and I dare say far more knowledgeable about brakes than I, but there is a dearth of information available to the average ‘Joe’ in one place.

If you want to see how the assessment of a caliper should look like, check my site at, and search for ‘caliper’, or “caliper 1000” or “caliper 1100”, etc.

I hope this helps someone to not get caught in the laissez-faire attitude seeming prevalent out there of those uncaring people just wanting to make a buck at your risk.

Ride safe.
Andy “StraightWings” Shanklin E&OE

A man who finds a job he loves will never work again.

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Re: Brake calipers, all years, but especially the early years

Post by joecoolsuncle »

what a great post! integrity is a lost trait in most of the world today. what you said about people selling junk while telling you it is the best on the market is also true in the new parts and accessories market.
Old Fogey
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1979 GL1000

Re: Brake calipers, all years, but especially the early years

Post by Old Fogey »

That article is truly special. You have covered EVERY single point that anyone refurbing their brakes MUST take note of. Well done, my hat's off to you, Sir!!
'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!

( Seriously, you haven't read all 115 pages of my website ?? :shock: )
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Re: Brake calipers, all years, but especially the early years

Post by JulianR »

Thank you for posting this very helpful information.
Old Fogey
Posts: 884
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Motorcycle: 1976 GL1000
1979 GL1000

Re: Brake calipers, all years, but especially the early years

Post by Old Fogey »

Blatent plug coming up!
You can find stainless pistons for all Wing models up to the 1500 on my site.
All four cylinders here:
1500 and many other Honda models here: ... sssteelbra

'Impossible' is just a level of difficulty! The only stupid question is the one you didn't ask first!

( Seriously, you haven't read all 115 pages of my website ?? :shock: )
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