Rear brakes!

[Valleyboy]

Not again everyone says!

I have not long ago replaced the SMC, full replacement not re-build. Also re-built rear caliper with new pistons and seals and new rubber boots for caliper/sliders.
This fixed my issues with rear brake.
However, slowly the issue has returned — I have a sticking rear brake.

I took the pads out, and rear wheel spins nicely.
I then tried moving the caliper on the sliding pins.
It feels like metal to metal contact and notchy when trying to slide the caliper - which it was not before.
after the last lot of work I made sure things moved nicely as they had new rubber boots and used silicone grease on sliders.
Im now stumped as to whats happened.
I cant take rear apart at mo as my torque wrench and large sockets are off elsewhere - so before I get to take rear wheel off, trying to think ***** has happened now!?
Do I potentially have a crooked rear bracket?
Previous owner had issues with rear as noted on it’s previous MOT of binding rear.

 

[Obo]

As I recall @Igofar had posted a photo of a rear caliper that had fluted grooves in where one of the bolts runs though. The solution was a new caliper.

Unfortunately there's lots of places for our brakes to break. (well at least not all the time.)

 

[SMSW]

I think what @Obo is talking about is the rear caliper stopper bolt. Did you follow the shop manual's procedure for reinstalling the rear caliper? The bolts have to be tightened in sequence, iirc. I'd also assume you did a full system brake flush with the new SMC - not just bleed, but pump two or three reservoirs of new brake fluid through each caliper.

Did you flush the clutch as well?

 

[Valleyboy]

Everything’s been flushed, clutch, front and rear - probably used about 3/4 litre going through the rear on its own. Will try another flush through incase.


caliper sliders themselves weren’t undone - pulled bracket off bike and taken off sliders.
Caliper halve bolts re-torqued after re assembly.

aware that previous owner may have shortcutted to get things done, so when I eventually get all my tools together will inspect for any damage/marks.

as an update, during lunch - took the pads off and had a closer look, they are aftermarket pads (I have an OEM set ready to install, but rather fix any issues first) - while pads were out had another go at sliding the caliper. If i tilt it ever so slightly it moves smoothly - it’s only notchy if in its resting position and trying to move it.
Who knows, the pads may be the issue?!
Put back together and stomped on rear pedal a bit, pushed round car park grabbing front brake - rears a bit better for now.
Cheers

 

[Mellow]

Yes, some have ok experience w/aftermarket pads but most go with OEM. I would try that first since it's the easiest thing to try.

 

[core-aggie]

took the pads off and had a closer look, they are aftermarket pads (I have an OEM set ready to install, but rather fix any issues first)

I, myself, consider aftermarket pads an issue.

I bought EBC pads[1] at the very first pad change, thinking I'll save a bit of ca$h, but I was absolutely rwong. I ended up spending MORE ca$h, because after 1,000 miles or so, I swapped the EBC for Mother Honda pads.

Guess what - all the pad issues disappeared. Have continued to use Honda pads since.

And if I remember correctly, the EBC didn't package the proper pad backings.

[1] I used EBC pads on my way-back-in-the-old-days 'Busa, and didn't have issues, so I thought, "why not". Doesn't apply to the ST13.

[Sidenote] I also used Honda pads on other Hondas I've had.

 

[Valleyboy]

Been trying to ascertain which manufacturers pads are on back at the mo….
They are using the oem heatshields, but those could have been taken off original pads.
They arent EBC’s,
Look like SBS pads but with the oem heatshield applied.

they are made up of 4 blocks on each side, but not individual as oem - looks like 1 big bit of material with the gaps cut into it to make up 4 bits.

anyway, will try fitting the OEM pads on weekend, hopefully these dont get damaged and fix the issue. Fingers crossed!
cheers!

 

[Igofar]

Can you post a couple pictures of your rear pads for us, I may be able to identify them for you.
IF someone tried to place the Honda OEM head guard on the back of a NON-OEM pad, it may throw the fitment out the window.
I would strongly recommend NOT mix and matching parts that could cause a very serious safety issue.
I'm concerned that I'm not understanding some of your statements, and just want to get a clear understanding of what you have done so far.
Please explain this comment:
"caliper sliders themselves weren’t undone - pulled bracket off bike and taken off sliders.
Caliper halve bolts re-torqued after re assembly."
Did you at any time, remove the three bolts that hold the back of the caliper together?
If so, there are torque specs in the manual that have been found incorrect in several different versions of the manuals.
When/If folks torqued these fasteners down with too much torque, it caused the STEEL bolts to swage into the soft ALUMINUM housing, and could cause the caliper to not sit square etc.
Too much grease on the sliders can also cause issues with too much suction, and not allow the caliper to release etc.
The clip in the roof of the housing, can also be tilted and not seated square causing the tab to drag (metal sounds) on the pistons etc.
(I'll try and post a picture of this damage after I post this reply)
If you post a picture of your rear caliper mounting bracket from the right side of the bike, looking through the wheel, to see wear/damage on the bracket itself.
When the SMC dies, it usually takes out this bracket as well.
If the front clip (silver one that the pad foot rests in) wears down the aluminum on the lower edge, it allows the pads to shift around, and puts a bind on the rear pistons etc.
Again, if you provide a picture for us, of the stopper plug hole, and the right rear side of the caliper bracket (front) I can tell you if its damaged or not.
Folks mistakenly rebuild the rear caliper, instead of replacing the caliper bracket that has been damaged, and the problem comes back.

 

[Igofar]

Clip damage pictures

 

[Valleyboy]

Thanks very much for photos,
I’ll try take some and post when I have them.
I did split the caliper, can’t remember if I went on haynes manual or the 2003/2004 service manual which is 32Nm for the 3 bolts joining caliper together.
i also installed a new pad retaining pin and new o-ring.
Cheers

 

[Valleyboy]

Got this one from right side of bike looking at back of caliper, will take more and get pads out, might take heatshield off to see if manufacturer named? Also look like adsl pads…. Which doesn’t fill me with joy might be tomorrow by time I get more photos.
Cheers again!

 

[Valleyboy]

Struggling to get photos at moment, my 1 year old boy wont go to sleep - by the time he eventually does it’s getting dark
Anyway, quickly managed to get rear pads off to take photo.
Tiny sign of heat to the pads!
I took the backing plate off and there’s some raised writing (very small) but it’s illegible and as it’s bloody raised potentially something messing up the backing/heatshield! Only a fraction of a mm high, but shouldn’t be there imo!

 

[Igofar]

That's some serious signs of heat.
Glad you caught it before you damaged your very expensive rear rotor, and/or brake lines.
Keep us posted as you can.

 

[etalors]

I think what @Obo is talking about is the rear caliper stopper bolt. Did you follow the shop manual's procedure for reinstalling the rear caliper? The bolts have to be tightened in sequence, iirc. I'd also assume you did a full system brake flush with the new SMC - not just bleed, but pump two or three reservoirs of new brake fluid through each caliper.

Did you flush the clutch as well?

What is the correct procedure for reinstalling the rear caliper. Can you quote the page in the manual. Thanks.

 

[Valleyboy]

Right…
Tools gathered, took opportunity to put on the oem pads. Bracket and caliper removed, caliper slid off bracket and cleaned pistons. Pistons pushed back into caliper with bleed valves opened.
on checking the bracket I did notice the pad retainer has some slight movement on the inner side and can see the bracket has been worn slightly, not sure if it’s world ending though yet - everything else checked out.

new pads installed, greased etc and re- assembled.
An additional bleed of rear caliper undertaken (minus pcv). Things are a lot smoother on the rear, however only a few rides and time will tell.
if issue persists then potentially new bracket required to sort out the play on pad retainer.

we shall see.

 

[Willsmotorcycle]

Having had a few back brake issues myself, I was curious about the order of installation. @Igofar has instructed me multiple times on setting the caliper then tightening the axle. Is your axle bolt torqued while you are doing all this? If previous owner had it slightly off you may need to loosen the axle, then set the caliper. Or maybe I need another cup of coffee.

 

[Valleyboy]

This is only the second time I’ve had caliper off, I pumped rear brakes up before torquing rear axle this time. Still think the bracket may be a potential long term issue as the right hand side of the retaining slider can move up and down slightly - so think damage has been done already.
With the new oem pads we shall see how it goes

 

[SMSW]

What is the correct procedure for reinstalling the rear caliper. Can you quote the page in the manual. Thanks.

The brake section is 17. The rear caliper installation is 17-52. I was talking about the need to tighten the stopper bolt first before tightening and torquing up the axle. Note my manual is for '03-'11 with slightly different instructions for before and after the '08 changes. The manual calls for a new bolt every time it is removed, I just clean it and apply blue loctite. I also use my torque wrench when a torque spec is provided. A lot of guys use their wrist to determine torque, but mine falls out of calibration without regular use.

 

[Igofar]

You’ve done a couple things wrong here.
Pumping up the brakes before torquing stuff can/will misalign the caliper and cause it’s own issues.
You cannot bleed just the rear section (minus the PCV) and get a correct bleed.
This alone could be much of your issues.
The bike needs to be bled in the correct sequence with all 7 bleeders.
The clip that is loose, is epoxied in place, as well as crimped from the factory, and should not move at all.
The wear you see is allowing the pads to tilt, not keeping the pistons square on the pads/rotors etc.
The stopper plug MUST be tightened BEFORE the axle nut.
I would suggest that you replace the rear caliper mounting bracket, install everything in the correct order, and flush the complete system in the correct sequence.

 

[Valleyboy]

No worries, not been out on it yet. Will partial dissemble and re-do once mini me eventually goes to sleep
The system has been fully bled previously, including pcv, this today was just to run a bit more fluid through. When Im allowed a day to work on bike will do another full bleed inc pcv.
will order a new bracket, but sadly need bike in meantime as it’s my only form of transport for work.

how come they are so expensive over here?! Sub £100 in some places abroad!