OEM replacement brake pad thickness

[dinodanny]

Does anyone know if the OEM replacement brake pads are thicker than the originals? I just changed mine for the first time and didn't notice that the new pads had raised the brake fluid above the upper level mark. As a result the master cylinder puked up some brake fluid onto the black upper fairing panel and marred it up. Since I can't stand to have my baby looking less than perfect I guess I'll be shopping for a new panel.

[Rhino]

You typically have to spread them wider than original to get them on the rotor. Not sure how its done at the factory but that's my guess as to why it displaces some fluid.

[B.D.F.]

I believe they are the same size. In fact, it would be really odd for any vehicle mfg. to use different pad sizes on new vehicles than they sell as parts for that vehicle.

What happens a lot of the time is that as the pads wear, people 'top off' the brake fluid in the reservoir. Then of course there is too much fluid in the system for the new, full- thickness pads and some of the fluid goes 'overboard'. Unfortunately this happens a lot and brake fluid is just plain old' aggressive, nasty stuff on plastics and paint.

Brian

Does anyone know if the OEM replacement brake pads are thicker than the originals? I just changed mine for the first time and didn't notice that the new pads had raised the brake fluid above the upper level mark. As a result the master cylinder puked up some brake fluid onto the black upper fairing panel and marred it up. Since I can't stand to have my baby looking less than perfect I guess I'll be shopping for a new panel.

[dinodanny]

What happens a lot of the time is that as the pads wear, people 'top off' the brake fluid in the reservoir.

No, I'm the original owner and the fluid has never been topped off. I figured OEM pads would displace the same amount of fluid as the originals so I didn't even check the level after I finished the pad install.

[B.D.F.]

Then the problem is what the other poster mentioned- pushing the pistons back further than they were when they would be when up against the pads. It is almost inevitable that that would happen though.

Brian

No, I'm the original owner and the fluid has never been topped off. I figured OEM pads would displace the same amount of fluid as the originals so I didn't even check the level after I finished the pad install.

[dinodanny]

Then the problem is what the other poster mentioned- pushing the pistons back further than they were when they would be when up against the pads. It is almost inevitable that that would happen though.

It wasn't till I went for a ride that the master puked up the fluid. After I did the pad install I pumped the brakes and checked several times for leakage and there was none. I had heard somewhere that Kawasaki had changed the pad compound. Maybe they increased the thickness too. The new pads seem to grab a lot better than I remember the originals doing.

[B.D.F.]

Well, I freely admit- you got me on this one. If the system held all the fluid for the install, the only thing I can think of that could possibly cause the fluid to expand afterward would be heating it. But if that happened, I would think the front brakes would have grabbed the rotors (without any input from the rider) and you would have noticed.... the bike stopping.

Besides all that, the entire brake system is sealed so I am not even sure where brake fluid could have escaped the master cylinder or reservoir.

I am going to have to chalk this one up to the unpredictable but whimsical gods of motorcycling- they must have been bored with throttle recalibration.... :-)

Brian

It wasn't till I went for a ride that the master puked up the fluid. After I did the pad install I pumped the brakes and checked several times for leakage and there was none. I had heard somewhere that Kawasaki had changed the pad compound. Maybe they increased the thickness too. The new pads seem to grab a lot better than I remember the originals doing.

[VirginiaJim]

After my previous escapade, I always check the master cylinder for either overfill or underfill.

[Conrad]

I just change my brake pads, front and rear, and replaced the OEMs with EBCs. After cleaning the brake pistons off I kept an eye on the master cylinders while I pushed them back into the calipers. After replacing the left front I noticed that the fluid level was getting close to the upper level so I pumped the front brakes up, thus lowering the level again, before I did the right front. Once the right side was done the level was near perfect after pumping them back up.

The rear needed to have a lil bit of fluid removed after I pumped them back up.

As for the thickness. I don't know about the total thickness of the pad assembly but I know for sure that the backing plates of the EBCs are thinner than the OEMs. 

[tomp]

FWIW, brake fluid does expand when heated, and that expansion has to go back into the reservoir. I thought the system was sealed, not vented, so I'm confused why it puked out, unless the cap screws or bleader were open/lose.   

 Sorry about the finish, but brake fluid hates some plastics and paint, and does its best to do evil upon them...

[Rhino]

FWIW, brake fluid does expand when heated, and that expansion has to go back into the reservoir. I thought the system was sealed, not vented, so I'm confused why it puked out, unless the cap screws or bleader were open/lose.   

 Sorry about the finish, but brake fluid hates some plastics and paint, and does its best to do evil upon them...

It's definitely vented because it has to allow for the pistons to move without creating a vacuum. That said, there is the rubber diaphragm that should seal the fluid from the air vent. So yes either the screws were loose or the diaphragm is compromised.

[B.D.F.]

Right- what you said in the second sentence: the system is sealed. The bellows allow the volume above the fluid to stay the same but the brake fluid is completely sealed inside the brake system.

By the way, every time I open a master cylinder, there is a lot of 'fluid' on top of the bellows, under the cover, etc. But that fluid is water that entered during rain, not brake fluid.

But back to the OP's post: nope, I have no idea what happened there either. The system should NOT spill brake fluid under any circumstances assuming it is working / sealed as it should be.

Brian

It's definitely vented because it has to allow for the pistons to move without creating a vacuum. That said, there is the rubber diaphragm that should seal the fluid from the air vent. So yes either the screws were loose or the diaphragm is compromised.

[VirginiaJim]

That cover gasket can get sideways really easily.  I've had that happen to me before.  You have to be careful and make sure it gets back in (easy boys) to seal correctly.

[Rhino]

Right- what you said in the second sentence: the system is sealed. The bellows allow the volume above the fluid to stay the same but the brake fluid is completely sealed inside the brake system.

By the way, every time I open a master cylinder, there is a lot of 'fluid' on top of the bellows, under the cover, etc. But that fluid is water that entered during rain, not brake fluid.

But back to the OP's post: nope, I have no idea what happened there either. The system should NOT spill brake fluid under any circumstances assuming it is working / sealed as it should be.

Brian

"bellows" was the word I was looking for instead of diaphragm. I've never had water on top of the bellows but until this year I lived in a dry climate and always parked in a garage. I haven't had the cover off since the move to TX. Now I'm going to have to check that out on both the front brake and the clutch.

[12menzer]

How many miles are you guys getting on your brake pads? 

[tomp]

How many miles are you guys getting on your brake pads?

The dealer where I bought my 08, changed pads all around, at purchase.  Bike had 20K miles on it.  I's sure the pads had to be worn out or they wouldn't have spent the money changing them. 

[12menzer]

ok, thanks.  I have 18K on my current pads.  I will check them.

[dinodanny]

How many miles are you guys getting on your brake pads?

At 17,500 miles a couple of my pads were down past the wear indicator grooves.

[h2smokin]

I did the rear pads today. 28k on the originals, I ride all highway for the most part though. Still have original fronts in