varying pad wear

[Catmandu2]

Just checking over my brake pads this evening,,, and noted that all 3 sets had different amounts of wear. There was only 1/16 left on the rears,,, which do wear much faster than the fronts,,, and I consider that normal due to the linked braking. But what surprised me was that the left front pads had 3/16 left on them,,, while the right front pads only had an 1/8 left. I am wondering why,, and if that frontal difference is normal. There is a delay valve on the RH side,,, yes ??? My brakes function very well. The front wheel spins freely,,, and the discs on both sides do not heat up from dragging. Any opinions explaining the variations ?? Cheers,,, Cat'

 

[ToddC]

They never wear 100% balanced....you are lucky yours are that balanced. Even in cars they wear un balanced.... extreme unbalanced is a sign of something is wrong........
Just my casual observation.........

 

[Al Gully]

I've had my 2005 since 2009 and never took the calipers apart to lube up the slider pins and thinking that is the cause of my left inner pad to wear a bit faster than the othe 3 front pads. What I've done in the past is take the left inner pad when it"s down to say 3/32" and move it over to the right outer pad. Gets me a few thousand extra miles when I change out the front pads.
I can wear them all down to a 1/16" if I do this swap.

 

[ST1100Y]

IMHO two contributing factors:
Due parking on kickstand the RHS rotor corrodes, increasing abrasion.
Neglected calipers causing it to stuck/delay in release.

... transmitted from a CAT S60 thing ...

 

[EA6BMECH]

They might need to be rebuilt. PITA to a point, but if the orings get dirty and the piston gets gummed up, it will affect it. But if they seem to brake ok and the pistons will push in somewhat easy, might just live with it, but I see you have an '04. IMO, I'd say rebuild them and make sure you use a caliper grease on the new orings and clean up the pistons with some used skotch brite. My 2 cents.

 

[dduelin]

Closing on 180,000 miles on my '05 and note nothing unusual with that kind of wear.

 

[Catmandu2]

Thanks for the replies, guys. You know,, I really should not post after midnight. I see that I mixed up the wear rates. Remaining pad thickness is 3/16 on the right hand pads,,, the side with the delay valve. The 1/8 remaining thickness is on the left side,,, the side with the smc. Yes,, the cause could be sticky pistons on the right, and/or the delay valve could be bringing in pressure to that side later in each braking cycle (as it is supposed too). I am not worried about it,,, as the braking is very positive. I just thought it was noteworthy and interesting. I use OEM pads,, btw.

On another related question,,, did braking get even better at one model year,,, when caliper sizes increased ?? Cheers,, Cat'

 

[SMSW]

Just cleaned, bled and otherwise serviced my brakes as part of winter layup (just had another snow squall). Front pads were almost exactly half worn, and within a millimeter of each other. Wear was about the same side to side and inner vs. outer. Rears were also about half worn. When I say half worn, I measured the pad thickness (up from the backing plate) when new, and used an old toothbrush to clean out dust and debris from the worn pads, then measured the pad material left. I must admit I was surprised how evenly worn the pads were.

 

[Igofar]

I guess I'll weigh in and make a couple comments on this topic....
Pads should wear evenly, or very close to it, on both sides. When the right side is wearing more than the other side, it could be indicating that the sliding pin is dry or dragging, the piston(s) may be dirty, the clips are dragging etc.
When (if) your front brakes are wearing differently, it could also mean that your rear brakes are dragging due to this (linked system) this could be why your rear brakes are wearing more.
If anything in the brake system is out of sync, I would flush & bleed the system to eliminate that from the problem, clean all (3) calipers, lube all (3) alignment dowels, clean the hanger pins and place a small amount of lube on them, make sure the metal backing cage is lined up perfectly with the eyelet the hanger pin goes through (so they don't scrape and drag on hanger pin while brakes are applied), and make sure the pistons/seals are clean and lubricated.
I would then inspect the SMC pivot point needle bearings and make sure the spacer is polished and bearings are packed with waterproof grease, also lubricate the head of the lower pivot point bolt, as it works as a bearing surface and can cause binding.
I would also inspect the SMC and test it to see if that was a contributing factor.
I (WOULD NOT) recommend using any kind of Scotchbrite on the pistons, as it could wear through the finish and create scratches that would gather and collect dirt faster. I find a piece of Paracord (with the inner white strands removed) will lay flat, is slightly abrasive, and will polish the pistons nicely when used with new brake fluid or simple green etc. You can loop it around the piston and saw it back and forth for a quick clean without scratching anything, a flat sneaker shoe lace will also work.
One last thing I would recommend, is something I have not heard anyone else mention....once a month, take a compressor, or canned air, and blow out all the dust from the calipers (roof area), this will assist the pads in lasting longer, as all the brake dust packed in there can cause wear too.
Ok, I'm tired, time to go lay back down...
Ride safe everyone.
Igofar

 

[nt650hawk]

Stiction of the piston dragging on the rubber seal because of grime contribute to additional pad wear. Every othe rpad change i pop outthe pistons an polish then with a wheel. This removes any grime on the pistons. I rub the seal in with my finger nails to remove any grime. The reassemble.

the pistons now have much less stiction and the draw of the master cylinder along with the kiss of the rotor on the pads produces less pressures of the piston pressing the pads into the rotor. therefore, less uneven wear

 

[jfheath]

I assume that the pads taken from one caliper are worn down by the same amount ??? You don't state that specifically.

How much do you use your rear brake pedal when riding ? The delay valve only acts on the right hand centre piston when the rear brake is applied, and then only as the brake pressure is increased. The delay valve has no effect when the front brakes are applied - both are applied equally. If you just use the rear brake mainly to steady the bike in slow manoeuvres, then maybe it is just not enough to apply the front right.

ST1100AY commented on the possibility of the right disc rotor being more corroded after a wet ride, and grinding the pads down the first few times the brakes are applied before they clean off the rusty surface. I can't say I have noticed that effect, but it is possible.

on Larry's suggestions.


I'll add to that the possibility that the spring clip in the roof of the caliper is at fault. In the 1300 2004 model (and all models up to 2007), it is possible to install the clip the wrong way round. The wider strip fits closest to the pistons. If it is the wrong way round, the pistons will eventually push the pads off the narrow strip, and this will the pads from releasing properly - at least until they wear down a bit more.

Also, the narrower strip has a little tag on it which should keep the pad that is furthest from the pistons held in its correct place. This tag can prevent the caliper from moving correctly if pads have not been inserted correctly at some time - as the tag may have been bent.

The 1300 from 2008 onwards has a similar tag arrangement, but it is impossible to fit the clip in the wrong way round on the newer front calipers.

 

[Igofar]

I assume that the pads taken from one caliper are worn down by the same amount ??? You don't state that specifically.

How much do you use your rear brake pedal when riding ? The delay valve only acts on the right hand centre piston when the rear brake is applied, and then only as the brake pressure is increased. The delay valve has no effect when the front brakes are applied - both are applied equally. If you just use the rear brake mainly to steady the bike in slow manoeuvres, then maybe it is just not enough to apply the front right.

ST1100AY commented on the possibility of the right disc rotor being more corroded after a wet ride, and grinding the pads down the first few times the brakes are applied before they clean off the rusty surface. I can't say I have noticed that effect, but it is possible.

on Larry's suggestions.


I'll add to that the possibility that the spring clip in the roof of the caliper is at fault. In the 1300 2004 model (and all models up to 2007), it is possible to install the clip the wrong way round. The wider strip fits closest to the pistons. If it is the wrong way round, the pistons will eventually push the pads off the narrow strip, and this will the pads from releasing properly - at least until they wear down a bit more.

Also, the narrower strip has a little tag on it which should keep the pad that is furthest from the pistons held in its correct place. This tag can prevent the caliper from moving correctly if pads have not been inserted correctly at some time - as the tag may have been bent.

The 1300 from 2008 onwards has a similar tag arrangement, but it is impossible to fit the clip in the wrong way round on the newer front calipers.

Morning John, Quiz time....
Go out and put your bike on the center stand, spin the front wheel, then apply the foot brake...if working correctly, the front wheel will abruptly stop! Linked system mate.
You can't use your rear brake pedal to steady the bike for slow stuff without applying the front brake as well.
Hope all is well with you.
Larry

 

[jfheath]

You can't use your rear brake pedal to steady the bike for slow stuff without applying the front brake as well.

Hi Larry - good to see you back on here !

I thought you knew me better than that by now - That was exactly my point - the fact that when using the back brake pedal, the front caliper centre pistons are applied - but not simultaneously - the left caliper centre piston is applied first. Which may means that if Catmandou is using the pedal a lot for low speed control, then it may explain the slightly greater wear on the left side. I believe the delay valve is a pressure related delay so as the pressure increases, the front right centre piston is brought into play. That's what I understand from what I have read and from Anna's Dad's excellent cross sectional diagram of the delay valve.

Not that I have put any of this to the test, nor do I know how much extra pressure is required to activate the front right centre piston as well. Maybe a future experiment. Or not !

 

[Igofar]

Hi Larry - good to see you back on here !

I thought you knew me better than that by now - That was exactly my point - the fact that when using the back brake pedal, the front caliper centre pistons are applied - but not simultaneously - the left caliper centre piston is applied first. Which may means that if Catmandou is using the pedal a lot for low speed control, then it may explain the slightly greater wear on the left side. I believe the delay valve is a pressure related delay so as the pressure increases, the front right centre piston is brought into play. That's what I understand from what I have read and from Anna's Dad's excellent cross sectional diagram of the delay valve.

Not that I have put any of this to the test, nor do I know how much extra pressure is required to activate the front right centre piston as well. Maybe a future experiment. Or not !

I know I was just having some fun with you, since you probably have forgotten more than I know.
I'm on the mend...just very slowly.
Happy belated birthday my friend.

 

[dduelin]

You can use the rear brake to steady the bike in corner entry. We do it all the time trail braking with rear pedal. During trail braking into the corner rear brake pressure is progressively bleeding off and the amount of front brake applied is very little with light pedal pressure acting on just 2 of the 6 pistons up front.

The SMC test with the bike on the center stand only has to stop the mass of just a wheel/tire assembly with only hand pressure rotating it. It's different when the kinetic energy of 900+ moving lbs is applied to the front contact patch. Honda made this LBS very transparent, in use it's almost like it is not there.

 

[Igofar]

You can use the rear brake to steady the bike in corner entry. We do it all the time trail braking with rear pedal. During trail braking into the corner rear brake pressure is progressively bleeding off and the amount of front brake applied is very little with light pedal pressure acting on just 2 of the 6 pistons up front.

The SMC test with the bike on the center stand only has to stop the mass of just a wheel/tire assembly with only hand pressure rotating it. It’s different when the kinetic energy of 900+ moving lbs is applied to the front contact patch. Honda made this LBS very transparent, in use it’s almost like it is not there.

I have no dog in this fight, but we'll have to disagree once again, many of us mere mortals don't have the super human ability to press on the rear pedal and be able to keep the front brakes from working (linked braking system).
With many years of racing under my old Bates leathers, I do understand what trail braking is, how it is used, and what its limitations are...however, I also know that when you have a linked system, you cannot use just your rear pedal gently in an attempt to keep the LBS from doing its job.
:BDH:

 

[dduelin]

Another illustration of just how little front brake is applied from light pedal pressure is the ability of the ST to make tight low speed turns dragging rear brake against throttle. Every experienced rider knows you can’t use much front brake in full lock circles but it’s a breeze with this version of linked brakes.

https://www.youtube.com/watch?v=jtQcmBE8xtE

 

[Igofar]

Another illustration of just how little front brake is applied from light pedal pressure is the ability of the ST to make tight low speed turns dragging rear brake against throttle. Every experienced rider knows you can’t use much front brake in full lock circles but it’s a breeze with this version of linked brakes.

Maybe this explains the 8 tip overs you have listed

 

[dduelin]

Yup. And 7 of them over 10 years ago when I was learning to handle the ST like this, heck this video is over 10 years old.

The ST takes slow speed drops like a champ. I replaced a few tip over wing covers but never scratched any plastic or stainless steel.

Glad to see you back to your old self.

 

[Igofar]

I was unable to get the video to work
I dropped 1 ST1100 about 15 years ago...my co-worker thought it would be funny to put a disc brake lock on my front wheel without telling me.
They do go down fast don't they!
Like you, I got lucky and only had a scratched tip over cover.
The 1100's fall better than the 1300's. I've seen 1300's Roll Over onto the tank on a off camber road when attempting to stop.