Replacing Brake Pads Difficult, Don't Think So
<img width="200" height="174" class="floatleft" src="motorcycle.in.th/images/articles/Replace_Motorcycle_Brake_Pads_Difficult_1.jpg" alt="" />When it comes to safety, efficient brakes are right at the top of the list so keeping them in tip-top condition should be high on your list of priorities. Working on your brakes can be a little daunting but so long as you take your time and follow the following steps-by-step guide, you'll be on your way to arm wrenching stopping power in no time.Here we have an everyday, common or garden brake caliper. The one we look at is a radially mounted but if you own a bike with conventional calipers, fear not as all the steps are exactly the same. Note the amount of grime around the calipers: although pads are asbestos free now-a-day, it's still a very good idea to ear gloves when working on brakes.
Before you remove the caliper from the fork leg, it's a good idea to loosen the brake pad retaining pins, particularly if they're the threaded type. Even if they're not, removing things like R clips and Clevis pins with the caliper held in place is a lot easier than wrestling with a loose caliper and risking damage to the fork leg.
The next stage is to remove the caliper from the fork leg. Make sure you use the right size socket for this, as it's very easy to cause damage to caliper bolts. If, like the motorcycle we’re working on here, it comes with Allen bolts, then rather than risk rounding the head off with a cheap Allen key, invest in a quality Allen socket - it will make your life a whole lot easier.
Remove the brake pad retaining pins and anti-rattle shims from the caliper, being sure to support its weight - never let it hang from the hoses as this is likely to cause damage that could lead to a fluid leak and ultimately, brake failure. Take care when removing the shims and note any markings that denote which way they fit. A good tip here is to take a few pictures with your digital camera or mobile phone - that way you can always check back and compare.
When you have the new brake pad on the left, and the worn one on the right compare it completely. Also check if the old brake pad dissipated heat efficiently. Also inspect the surface of the old brake pad.
It's possible that the surface of the old brake pad has become glazed. This is a common occurrence often caused by the on and off action of riding in traffic or just through infrequent use. It can be easily remedied by the light application of 800-grit glass paper, so it's not a big problem. However, in this case the pads are worn enough to warrant replacement. We've gone for original replacements as the customer rides mainly on the road. For race or track use we'd opt for a pad with higher operating temperature - on the road these are worse than standard so be sure to know what you've getting.
Cleaning the caliper before the pistons have been moved is vital to stop tapping any brake dust or road grit in the rubber caliper seals. While purpose-made brake cleaners sprays are easy to use, most top race teams use good old Fairy liquid, hot water and a brush. The washing up liquid doesn't damage seals like some aggressive cleaning sprays and does a great job of getting rid of all the dirt.
Work the soapy water into every nook and cranny. Use an old toothbrush for the smaller parts, paying special attention to the pistons - they should be gleaming by the time you've finished. Inspect for any pitting to the pistons and for any damage to the delicate dust seals.
Carefully rinse the caliper with hot water. Once you're absolutely certain that everything is pristine and that there is no grime lingering around the pistons, carefully push them back evenly, a bit each at a time with your fingers. Don't rush this and be careful that an opposing piston doesn't pop out. Removing the brake fluid reservoir cap will reduce back pressure and make this much easier.
As you squeeze the pistons back into the caliper, make sure that the fluid level hasn't risen too much as you push the fluid back to the reservoir - brake fluid as a lethal effect on paint. If you do spill any, rinse off immediately with lots of water - don't wipe it! The best way to make sure this doesn't happen is to take your time and if necessary use a syringe to suck out any excess - these can be easily obtained form your local pet shop or pharmacy.
With everything now immaculately clean, refit the pads into the caliper. It's a common misconception that everything needs to be swathed in copper grease, but less really is more - grime and grit stick to nothing better than a well-greased brake pad. Use a light dab of the pins and caliper bolt threads but nowhere else. Modern calipers and pads are precision-engineered units these days - huge dollops of grease really aren't necessary.
Before you even think about testing your new pads working in their recently cleaned environment, pump out the brake pads gently. Don't pull the level all the way back to the bar, just use light half or less stroke movements until the lever becomes firm. Go for a spin and use the brakes as normal. Don't listen to old men with beards that tell you how to 'bed them in' as you'll end up glazing them and then having to repeat the whole procedure again...
