About to start crying

Well, thought I'd prepare my bike (1999 zx6r) for its MOT. The main
problem was the brakes, the pads were completely worn, the pistons
seemingly frozen, and the brake fluid pretty gunky.

I bought some new pads, some brake dust cleaner and some brake fluid.
Bearing in mind that Ive never done this sort of thing, I thought Id
take the calipers off the forks because I reckoned it would be easier
cleaning them unattached. Got them fairly clean. So far so good.

I attached them back on and changed the bike fluid, so that I could
then force the pistons out of the casing and finish off the cleaning.
Again, seemed to go without a hitch, all the air bubbles were out, both
sides done.

I was just finishing this little job by fastening the final bleeding
screw back, and all of a sudden it seemed very easy to turn. I hadnt
unscrewed it very far, so i turned it just a little bit more, and a bit
more, until it went incredibly easy to turn - the case surrounding this
little screw had just come off completely - snapped! Hardly any
pressure whatsoever!

Oh my, I've just had a quick look on the t'internet at prices for this
front right caliper, and they all seem to be about £500 (UK). I cant
afford these sort of prices! Please someone tell me theres another way
of recovering my situation other than forking out for a new pair of
calipers.

Yours Desparately

Steve

 

Don't get depressed. Get busy fixing the problem so you can go on to
better things.

Start checking ebay, and call up all the breakers in the country to see
what you can buy used.

An alternative would be to take the caliper to a really good
trustworthy machinist and have him rework the damaged caliper. This
might involve welding the original hole shut and redrilling and tapping
the bleeder screw hole, unless you can find oversized bleeder screws.

When it comes right down to the nitty gritty, you do not need those
bleeder screws anyway, after you get the caliper full of brake fluid.

If you unbolt the calipers and let them hang straight down, you can put
a piece of 1/4 inch steel plate between the pads to keep them from
blowing out as you pump the lever, all the air bubbles will rise up the
hoses to the master cylinder reservoir.

That's how I bleed brakes.

Or, if you can find a trustworthy welder, just have the damaged bleeder
hole welded shut and install a bleeder style banjo bolt where the brake
hose attaches to the caliper.

Google for "bleeder banjo"...

I think Galfer or some manufacturer of steel braided aftermarket brake
hoses makes banjo bleeders for about $15 USD.

The main idea for the banjo bleeder is to install it up at the master
cylinder so you can bleed out the air bubble that accumulate in that
critical area.

Air bubbles right there cause the front brake lever to feel spongy and
riders keep trying to bleed the air out down at the caliper and have no
success getting the air out.

For some reason, riders don't seem to understand that air bubbles rise
and brake fluid goes to the lowest point in the system.

If you find metric banjo bleeders, they will probably come in 10 and 12
millimeter diameters with two or three different thread pitches. You
must get the correct thread pitch or you'll just cross thread the
damned things. Thread pitches are typically
0.75 mm, 1.0mm, 1.25mm and 1.5mm, with the most common used being 1.0mm
between threads.

 

Have you checked used prices? I've seen complete front brake systems go
for $1-200 on eBay in the past. People sell them when they crash the
bike or when they put on aftermarket brakes.

Even if you get a dirty set, you can strip and clean them, replacing all
seals, any corroded pistons, etc. This would be a good time to consider
adding speed-bleeders (http://www.speedbleeder.com/) if that seems
worthwhile. Some people really like them, I just haven't bothered since
I've get access to a MightyVac setup (pump the fluid in from the bottom
of the system, slowly, and bleeding is usually not necessary, IME).
You'll want the workshop manual for the disassembly, and people here can
walk you through the process too, most likely. fwiw, BIKE had a sidebar
or article about doing this procedure on a CBR900RR late last year. I
could look up the article if you wanted to try and track it down.

As for the desperation, take three deep breaths, assess the situation,
and make a plan. If you get frustrated, take some time off. I've found
that no matter how important or time-sensitive a project is, I'm better
off taking some time off rather than working while upset. I forget less,
I break less, I hurt myself less. I guess I'm trying to say that I've
been there too.

Finally, this example really makes the case for regular brake caliper
cleaning and fluid change. I change my fluid every year or two and clean
and lubricate the calipers at least once per year. I've decided that
cleaning the pistons and lubricating the slide-pins (yeah, yeah,
2-piston sliding calipers on the VFR...bite me) makes more difference to
my braking feel than adding the braided SS lines (not that I'm sorry to
have done that, mind).

HTH, and good luck with it.

--
Later,
John



'indiana' is a 'nolnn' and 'hoosier' is a 'solkk'. Indiana doesn't solkk.

 

<snip>

I was just finishing this little job by fastening the final bleeding
screw back, and all of a sudden it seemed very easy to turn. I hadnt
unscrewed it very far, so i turned it just a little bit more, and a bit
more, until it went incredibly easy to turn - the case surrounding this
little screw had just come off completely - snapped! Hardly any
pressure whatsoever!

<snip>

Sounds like a simple Helicoil job. Go to a good mechanic
(really good - you already found out brake callipers are
expensive) and there is a very good chance he'll make
the threads better than new (at a reasonable cost).

 

My friends & I have installed oversize bleed screws in more than a few
calipers (it's always fun to discover you need two or three different size
wrenches -- in a mix of English & metric -- to do a brake bleeding job). A
good tap&die set can cure a world of problems, especially when you're
dealing with threads cut into aluminum, or in places where you're frequently
loosening & re-tightening -- like bleed screws.... (We eventually stopped
allowing one guy to put in bolts & screws in delicate places because he had
big hands & no sense of when a bolt was already stretching...)
Whenever I've bought an old used vehicle, one of the initial maintenance
jobs I do or have done is draining the entire brake system & refilling with
fresh fluid. Brake fluid is hygroscopic and that moisture will, over time,
rot out any brake system. I just love it when mechanics look at me fisheyed
when I tell them to do this drain&refill&bleed on a vehicle with sludgey 10+
year old brake fluid in its system...
With the cost of new parts, eBay becomes your friend. If you don't find what
you need at a good enough price, just keep doing the same search week in &
week out, and eventually almost everything shows up at one price or another

Don't get depressed. Get busy fixing the problem so you can go on to
better things.

Start checking ebay, and call up all the breakers in the country to see
what you can buy used.

An alternative would be to take the caliper to a really good
trustworthy machinist and have him rework the damaged caliper. This
might involve welding the original hole shut and redrilling and tapping
the bleeder screw hole, unless you can find oversized bleeder screws.

When it comes right down to the nitty gritty, you do not need those
bleeder screws anyway, after you get the caliper full of brake fluid.

If you unbolt the calipers and let them hang straight down, you can put
a piece of 1/4 inch steel plate between the pads to keep them from
blowing out as you pump the lever, all the air bubbles will rise up the
hoses to the master cylinder reservoir.

That's how I bleed brakes.

Or, if you can find a trustworthy welder, just have the damaged bleeder
hole welded shut and install a bleeder style banjo bolt where the brake
hose attaches to the caliper.

Google for "bleeder banjo"...

I think Galfer or some manufacturer of steel braided aftermarket brake
hoses makes banjo bleeders for about $15 USD.

The main idea for the banjo bleeder is to install it up at the master
cylinder so you can bleed out the air bubble that accumulate in that
critical area.

Air bubbles right there cause the front brake lever to feel spongy and
riders keep trying to bleed the air out down at the caliper and have no
success getting the air out.

For some reason, riders don't seem to understand that air bubbles rise
and brake fluid goes to the lowest point in the system.

If you find metric banjo bleeders, they will probably come in 10 and 12
millimeter diameters with two or three different thread pitches. You
must get the correct thread pitch or you'll just cross thread the
damned things. Thread pitches are typically
0.75 mm, 1.0mm, 1.25mm and 1.5mm, with the most common used being 1.0mm
between threads.

 

Well, thought I'd prepare my bike (1999 zx6r) for its MOT. The main
problem was the brakes, the pads were completely worn, the pistons
seemingly frozen, and the brake fluid pretty gunky.

I bought some new pads, some brake dust cleaner and some brake fluid.
Bearing in mind that Ive never done this sort of thing, I thought Id
take the calipers off the forks because I reckoned it would be easier
cleaning them unattached. Got them fairly clean. So far so good.

I attached them back on and changed the bike fluid, so that I could
then force the pistons out of the casing and finish off the cleaning.
Again, seemed to go without a hitch, all the air bubbles were out, both
sides done.

I was just finishing this little job by fastening the final bleeding
screw back, and all of a sudden it seemed very easy to turn. I hadnt
unscrewed it very far, so i turned it just a little bit more, and a bit
more, until it went incredibly easy to turn - the case surrounding this
little screw had just come off completely - snapped! Hardly any
pressure whatsoever!

Oh my, I've just had a quick look on the t'internet at prices for this
front right caliper, and they all seem to be about £500 (UK). I cant
afford these sort of prices! Please someone tell me theres another way
of recovering my situation other than forking out for a new pair of
calipers.

Yours Desparately

Steve
been there did that ! Get yourself a good quality tap & die set, some
larger diameter bleeders and its a piece of cake, the aluminum takes threads
very nicely.

Tom B