Told the brake pads are shot, how do I tell?

[HondaInTheSun]

Hi ST owners!

I recently learned that my brake pads need replacing, more context on that here if you’re interested:

Test rode a BMW K1600 and K1200 today... | BMW

A quiet Friday at work had me curious...are those big BMW bikes I see on the highway as amazing as I suspect they might be? I swung by our local BMW dealership and had an absolutely wonderful, hassle free, test ride experience. I was interested in looking at the K1600, within 10 minutes of...

www.st-owners.com

How do I verify this for myself? They were clearly able to without taking the calipers off.

I’ve tried to attach pics here, but not sure if I’m capturing the right thing.

Thanks in advance for any help!

 

[motofisch]

Your photos (esp. the second) show the pistons extended well out of the caliper bores. As the pads wear the pistons extend to take up the place of the lost pad material. It seems you picked a great time to take a test ride and have someone take a look at your brakes. Catching this in time saved you a good deal of money.

 

[HondaInTheSun]

Your photos (esp. the second) show the pistons extended well out of the caliper bores. As the pads wear the pistons extend to take up the place of the lost pad material. It seems you picked a great time to take a test ride and have someone take a look at your brakes. Catching this in time saved you a good deal of money.

Super helpful! So basically I can tell by looking at the piston extension removing the need to be able to see the pads. Makes complete sense. Thank you!

Now to research if this is something I’m capable of tackling myself...

 

[docw1]

Here's a pic of used and new pads. It's from a CTX, but practically the same:
https://flic.kr/p/H9Zizy

 

[Rob20111]

Agreed, photo 2 shows best. You're all but done. Change them before they destroy your discs (rotors) too, or else it's a lot more $$$.
If someone else is doing the work for you ask them to save you the old pads then compare to new. You'll see right away.

 

[Al st1100]

They are not shot,, you can get at least another 5 miles or 5 minutes( which ever comes first)

 

[HondaInTheSun]

They are not shot,, you can get at least another 5 miles or 5 minutes( which ever comes first)

Not going to lie, that made me laugh out loud.

 

[ReSTored]

...........So basically I can tell by looking at the piston extension removing the need to be able to see the pads.

No, that's not really what he meant. The pistons being extended so much is a general indicator the pads are worn, but looking at a new pad shows how much pad material there was new and your picture shows that probably 90%+ of the pad thickness is gone and the backer plate is very close to the disk. So, yes, the pads are worn out and they need to be replaced before they touch the disk and destroy it.

 

[Larry Fine]

Remember to push the pistons back in together (slowly), using the old pads, or one will likely pop out.

 

[HondaInTheSun]

Remember to push the pistons back in together (slowly), using the old pads, or one will likely pop out.

Great tip. Thank you Larry!

 

[Mellow]

They are not shot,, you can get at least another 5 miles or 5 minutes( which ever comes first)

Ok, now they're shot.

 

[Andrew Shadow]

How do I verify this for myself?

See the attached page from the ST1300 owner's manual.
The cutouts referenced on that page can easily be seen in the picture attached to post # 4 above.

Remember to push the pistons back in together (slowly), using the old pads, or one will likely pop out.

Clean the pistons before you push them back in to the calipers.
Have a look at this article- ST1300 - Rear Brake Piston Cleaning

 

[dduelin]

These need replacing but to answer your original question, the pads have small rectangular wear indicators molded into the end of the pad. In Bill's post (#4) you can clearly see the dark rectangle on the end of the friction material, next to the metal back plate. To view front wheel pad wear I use a 2.5 inch square mirror and kneel down next to the bike with a flashlight. Held under the end of the caliper and using the flashlight to illuminate the pads, the mirror clearly shows how much pad is remaining to the wear indicator. The wear indicator is 1 mm high and since it is not unusual for pads to wear slightly cock-eyed (sometimes the leading edge of the pad wears more or less than the trailing edge), when about 2 mm of pad is remaining I pull out the pad retaining pad to check the pads out of the caliper. This picture shows the orientation of the mirror to look up into the caliper and view the pads. The flash of the camera does not illuminate the end of the pad like a flashlight will. This is a Goldwing but the mirror works just the same for the ST1300 front calipers. TO check the rear pads just peer in there with the flashlight to illuminate the end of the pads.

 

[Mcreviver]

Remember to push the pistons back in together (slowly), using the old pads, or one will likely pop out.

Clean them before you push them back in, or you are asking for a leak later. Better yet, consider new seals inside and fresh fluid.

 

[SMSW]

Tim, I've never seen that little wear indicator Dave mentioned in post 13. After a few miles, the pads are dirty and the caliper is covered with brake dust. This is a good reason to get in there annually with a toothbrush and clean things out, but it is not required by the Service Manual. Once you do one pad change you will know exactly what you are seeing when you look through the window at the edge of the brake pads. You can see the disk, the pad material, and the backing plate and it only takes about 3 seconds w/ a flashlight to ascertain roughly how far from the disk the backing plate is and therefore how much pad material is left. Larry does a complete bike inspection whenever someone brings him a bike; you have the disadvantage of living in a location where you can ride year round - there is no winter lay-up when us freezing guys service our bikes at our leisure. You might consider scheduling a once-a-year inspection/preventative maintenance time and change pads (and tires, etc) when it suits your schedule and not necessarily the bike's. As I said in another thread, I prefer to change things when I want to (winter) and not when the bike decides they have to be done. The latter is usually at an inconvenient time right before a long trip.

 

[Igofar]

Do NOT ride your bike any further until you sort your brake issues out!
To replace the rear pads, you should remove the rear wheel, so you have access to properly cleaning the caliper, pistons, clips, and greasing the guide pin.
I would also do the front set(s) at the same time, along with a proper brake bleed/flush.
The 1st thing I would check is the function of the SMC to make sure its working, if it is dying or dead, this could be what destroyed your pads so quickly.
And yes, there are several things you will need to know/learn to remove and install the rear wheel assembly correctly.
Standing by the white courtesy phone if needed.

 

[HondaInTheSun]

It never ceases to amaze me the help I get from this forum, truly an amazing group of human beings.

THANK YOU everyone for all the help and advice. I’ve never been mechanically inclined but with the help of this forum have found myself attempting things I never would have dreamed of touching. In the case of brakes, which feel like are a fairly critical safety component of the bike, this job may be outside my time and comfort level, but the feeling of support is amazing nonetheless.

Igofar has spoken, so I’ll be in my cage for the commute tomorrow...adding an additional hour to my workday...no lane splitting in the cage. The good news is, I have a strong incentive to get this sorted out.

Thank you all again!!

 

[rjs987]

Here's a pic of used and new pads. It's from a CTX, but practically the same:
https://flic.kr/p/H9Zizy

Thank Bill,
Them's be my pads one of the times I changed them on my (former) CTX1300 and posted the photo for others to see what a worn pad vs new looks like.. They are the same as for the ST1300. You can see the notch in the new pad where the pad material meets the backing plate. You can also see the same notch in the worn pad if you zoom in really close and look real hard. It's there, and shows that there is barely a sliver of brake pad left before getting into the notch. Not all pads have this notch, but most do. It's located so that you should be able to see it using a mirror and flashlight as Dave shows (@dduelin ) and would normally be visible from the same angle as in photo 2 that @HondaInTheSun posted. The main thing to note is the difference in thickness of the actual pad material. Those of the OP are definitely needing to be replaced.

BTW- After changing the oil and filter, replacing the brake pads was my next DIY project I ever attempted on a bike long ago. Well, not including my first bike anyway with which I removed the engine and had the cylinders re-bored and rebuilt the oil injector on my Harley (just HAD to have the total experience of owning one). But replacing pads is one of the rather easier jobs to do without messing up. Should be plenty of help to be found on this site for step by step doing that.

 

[Whooshka]

Remember to push the pistons back in together (slowly), using the old pads, or one will likely pop out.

But first clean those pistons with a tooth brush or shoe string soaked in brake fluid.

 

[mortenk]

When I read your BMW story I thought that the dealer was just trying to make an extra buck by suggesting new pads. Well - the pics show they were right for sure! But it's an easy job. As far as the leaking fork seals go, visibly check your forks first: if they are dry it indicates that seals are OK. If you see any oil around the forks, it's a sure sign that seals need replacement...