motorcycle disc brakes binding

Step 4: Un-sticking the pistonsShow All Items« PreviousNext »View All Steps DownloadBecause it could save your life. Most routine services don’t include cleaning and servicing the calipers unless the brake pads need changing or there happens to be a problem with them such as a partially sticking piston, or worse, a totally seized one. It pays to look after not only the shiny bits the eye can see, but also the not-so-shiny bits you can’t. A very simple piece of hydraulic equipment. Other than the obvious concerns over safety, provided you’ve got a decent tool kit and at least a modicum of common sense you should be more than equipped for the job. Don’t think about it if… You’re not bothered about having efficient brakes or possess zero common sense… A paddock stand is handy but not actually essential, a decent socket set (8-19mm minimum), a torque wrench, a slotted screwdriver, a set of combination spanners (8-19mm), a good quality set of Allen keys (4-10mm), a tin of brake cleaner, a tin of WD-40 or other penetrating oil, a washing-up bowl, some fine-grade 800 grit and 1500 grit ‘wet-or-dry’ emery paper

The biggest skill we all need for safe home spannering is patience.
motorcycle accident salem nh 1. Gently squeeze the brake pads against the pistons (eg away from the disc) by gripping them with the water- pump pliers against the caliper then remove the retaining pin(s) that are holding the pads in place. 2. Be careful as you withdraw the pin(s) that the spring-loaded ‘anti-rattle’ shim doesn’t fly off into the deepest, darkest corner of your garage. Use a parts tray or an old baking tin to store small parts and to catch dust and cleaning agent from the caliper. 3. Undo the caliper retaining bolts. On a conventional caliper they thread into the fork leg from the side of the caliper. Radial calipers mount through the back of the caliper. Lift the caliper clear of the disc being careful not to damage the mudguard (you could put an old T-shirt between the caliper and the wheel to prevent possible damage).

4. Inspect the caliper for obvious signs of damage. Spray brake cleaner directly at the pistons and agitate any stubborn dirt with an old toothbrush or washing-up brush. Do not use a wire brush – you can quite easily score the pistons and damage the seals if you are careless. 5. Gently pump the brake lever (without pulling it right back to the bar) while watching the action of the pistons. They should come out then return very slightly. If they don’t return, or you can’t push them back, the piston may be partially seized. Don’t panic, in 99% of cases, we can deal with this easily. 6. Clean the pistons with very fine wet-or-dry paper and WD-40. You can use 1200 grit, but 1500 grit is better (though harder to find). Unless your bike is brand new, there will be a coating of corrosion at the edge of the piston where it is exposed to brake dust and, in winter, road salt. 7. Make sure you clean around the whole outer surface of each piston by rotating the piston if necessary then easing the piston back in.

If it is too stiff to do by hand, gently use the water-pump pliers to push the piston back in. Work on one piston at a time until it returns easily. Repeat until totally free. 8. With the caliper now cleaner than it’s been for years, refit it to the fork leg. Apply a little copper grease to the bolt threads, do them up finger-tight, then fully tighten to the manufacturer’s recommended torque setting using a torque wrench. Now it’s time to inspect the brake pads in more detail. 9. Now we know the caliper is working to its full potential, let’s take a closer look at those pads. There is plenty of friction material left on them, but are they glazed? If the surface of the pad looks shiny, gently rub it with some clean, dry 800 grit emery paper (don’t whatever you do use oil this time) to take off the ‘sheen’ or ‘glaze’. 10. Clean the retaining pins, the backs and – just as importantly – the sides of the pads. The caliper should be clean already, but it won’t hurt to give the pad ‘seats’ a wipe.

Apply a little copper grease to the pins and the back of the pads – just don’t go mad with it – you don’t want it ending up on the pads' friction material or on the brake discs. 11. Reassemble the pads, pin(s) and anti-rattle shim(s) making sure it all goes back in the exact reverse order of dismantling. If you don’t have a workshop manual, refer to the pics you took with your camera/phone if you’re unsure of anything. You did take some pics, didn’t you? 12. Gently pump the brake lever to pressurise the braking circuit and to return the pads to their original position. On the road treat the brakes as if they are new and allow them to bed in for a good few miles. Marvel at how much better your brakes are, ‘accidentally’ pull a big stoppie and buy yourself a beer. You’ve just saved at least a hundred quid. Sign up or log in to customize your list. Here's how it works: Anybody can ask a question The best answers are voted up and rise to the top

The title says it all really. I've taken the front wheel off my mountain bike to get it in my car. When I get it out and try and put the front wheel back on the space between the brake pads isn't wide enough for the rotor. I must have pulled the front brake. How can I separate the the pads without damaging them? I have hydraulic disc brakes mountain-bike wheels disc-brake brake-pads As mentioned try a blunt bladed instrument (A large flat blade screwdriver will do) to pry the pads back in. Just put the screwdriver between the pads and lever the pads apart evenly! Just be carful though as sometimes the pistons that push the pads out can come out too far resulting in the pistons being slighly out of line, however if the pads have plenty of material left on them you should be fine to just lever them back in with the screwdriver, ther will be some resistance as you will also be pushing against the pistons and fluid pressure. I've used a (clean) drywall putty knife.

The blade is wider than a screwdriver, so there's less chance of gouging the pads. Slide the knife in between the pads, twist and pry a bit, and they open right up. I just had to look this up for a friend, who accidentally completely closed them. The recommended way, taken from "Zinn and the art of Mountain Bike Maintenance" is as follows. "Sometimes the pads in hydraulic disc brakes can rub because the pistons get pushed out too far, especially if the lever is applied without a rotor or spacer between the pads. You will have to push the pistons back in, usually by removing the pads and pushing the pistons back in with a plastic tire lever. On Hayes, the only thing pulling the pistons back in is the reversal of the twist the pistons apply to square-cross-section o-ring seals surrounding the waist of each piston, so the pistons tend to stay out too far once there. Pull out the pads, carefully push the pistons back in with the box end of a 10mm wrench(avoid pressing on the pin sticking out of the piston, which hooks the wire catch on the back of the pad), and replace the pad"