Mouse
Registered user
Last night I decided to clean my brakes and change the rear pads, which were pretty much worn out after about 5000 miles. I think this early death is partly due to the linked brakes and also my riding style, so I'm not particularly bothered about it. But don't rely on your pads lasting the full service interval!
While I was at it I removed the front calipers, cleaned the pistons and applied a bit of copper grease to the back of the pads and the pin that holds them in. I'll see if this cures the slight brake squeal I've been having.
By the way, all this is based on my experience with previous bikes, but if I've made a GS-specific mistake, please feel free to point it out!
Here's the front caliper, you can see the pads have loads of life left.
Before starting on the rear caliper, remove the silly rear mudguard thingy.
First step in removing the rear pads is to remove the small R clip that's through the pin, and then gently tap the pin loose with a drift and hammer. Tap from the offside, but don't fully remove it yet.
Next remove the caliper by undoing the two large torx bolts. The caliper and silver coloured slider can then be removed. The caliper mounts on the slider with two large pins with rubber seals round them. Slide the caliper free as shown in the photo. Clean the slider up a bit and put a small amount of fresh grease on the pins.
Next, remove the pad locating pin and the pads. Clean the caliper and pistons gently (I use a stiff nylon brush, never use a wire brush or abrasive paper on the pistons as they are made of nylon), and then GENTLY push the pistons back into the caliper. I was told by a BMW tech person that it's ok to gently push them back with your fingers, but don't push too fast or you bugger up the ABS pump.
Here you can see how much friction material was left on my pads, compared to the new pads.
Smear a small amount of copper grease on the back on the new pads, and on the pin. Push the slider pins back into the caliper and then fit the new pads. This part is a bit fiddly and hard to describe in detail - it may help if you have three hands
The pads can only be fitted one way round - note that the pad on the piston side is thicker. Don't attempt to push the pin all the way back into the caliper at this point, just put it in sufficiently to hold the pads in place.
Mount the caliper back on the bike, and then, using a hammer and drift, gently tap the pin all the way into place. You'll have to work through the rear wheel for this. You'll know when the pin is correct as you'll be able to see the small hole in it that the R clip goes through. Push the R clip through the pin, and then tighten the caliper mounting bolts to the correct torque (or if you're shabby like me, just tighten them )
Finally, turn on the ignition and apply the rear brake, to push the pistons and pads into position. Remember when riding that new pads take a while to bed in, so you won't have full braking power for 10-20 miles or so.
I didn't bother refitting the rear mud guard thingy, I'm going to experiment whether the bike gets less spray with it removed. So, just to annoy people, I put a nasty old screw in the mounting hole on the rear drive housing, to stop it getting full of dirt
I also habitually put a smear of copper grease on all bolts as I refit them - opinion may differ on this but I never have trouble with seized bolts.
So there you go. It was no different to changing the pads on any other bike really. And just as a point of interest, I noticed that the rear caliper is pretty much identical to the front one on my old Honda CB500! I hope this info is useful to some people, but remember, the brakes are a safety critical item, so don't mess with them unless you know what you are doing!
While I was at it I removed the front calipers, cleaned the pistons and applied a bit of copper grease to the back of the pads and the pin that holds them in. I'll see if this cures the slight brake squeal I've been having.
By the way, all this is based on my experience with previous bikes, but if I've made a GS-specific mistake, please feel free to point it out!
Here's the front caliper, you can see the pads have loads of life left.
Before starting on the rear caliper, remove the silly rear mudguard thingy.
First step in removing the rear pads is to remove the small R clip that's through the pin, and then gently tap the pin loose with a drift and hammer. Tap from the offside, but don't fully remove it yet.
Next remove the caliper by undoing the two large torx bolts. The caliper and silver coloured slider can then be removed. The caliper mounts on the slider with two large pins with rubber seals round them. Slide the caliper free as shown in the photo. Clean the slider up a bit and put a small amount of fresh grease on the pins.
Next, remove the pad locating pin and the pads. Clean the caliper and pistons gently (I use a stiff nylon brush, never use a wire brush or abrasive paper on the pistons as they are made of nylon), and then GENTLY push the pistons back into the caliper. I was told by a BMW tech person that it's ok to gently push them back with your fingers, but don't push too fast or you bugger up the ABS pump.
Here you can see how much friction material was left on my pads, compared to the new pads.
Smear a small amount of copper grease on the back on the new pads, and on the pin. Push the slider pins back into the caliper and then fit the new pads. This part is a bit fiddly and hard to describe in detail - it may help if you have three hands
The pads can only be fitted one way round - note that the pad on the piston side is thicker. Don't attempt to push the pin all the way back into the caliper at this point, just put it in sufficiently to hold the pads in place.
Mount the caliper back on the bike, and then, using a hammer and drift, gently tap the pin all the way into place. You'll have to work through the rear wheel for this. You'll know when the pin is correct as you'll be able to see the small hole in it that the R clip goes through. Push the R clip through the pin, and then tighten the caliper mounting bolts to the correct torque (or if you're shabby like me, just tighten them
)Finally, turn on the ignition and apply the rear brake, to push the pistons and pads into position. Remember when riding that new pads take a while to bed in, so you won't have full braking power for 10-20 miles or so.
I didn't bother refitting the rear mud guard thingy, I'm going to experiment whether the bike gets less spray with it removed. So, just to annoy people, I put a nasty old screw in the mounting hole on the rear drive housing, to stop it getting full of dirt
I also habitually put a smear of copper grease on all bolts as I refit them - opinion may differ on this but I never have trouble with seized bolts.
So there you go. It was no different to changing the pads on any other bike really. And just as a point of interest, I noticed that the rear caliper is pretty much identical to the front one on my old Honda CB500! I hope this info is useful to some people, but remember, the brakes are a safety critical item, so don't mess with them unless you know what you are doing!
