I'm going to explain you how to check rear brake pads on a 2008 Harley Davidson Road Glide. The first thing you need to do is remove the right saddle bag of your Harley and once you do that, it will give you access to the rear brake caliper part. The minimum friction of the material on the brake pads is 0.016 of an inch for this motorcycle. The brake pads do have wear indicator lines, but they're almost impossible to see with the brake pads mounted on the motorcycles so I'm going to remove this caliper part, remove the brake pads and measure the friction material with the brake pads off the bike.
The way that you get this brake caliper off is you remove these two big bolts. They're 5/16" and the way you get the brake pads out of the caliper is to remove the brake pad pin, which is 5mm. I don't know why these are metric Harley parts and these are standard, but that's the way they've done it. You can find all spare parts for rear brake caliper assembly here http://preview.tinyurl.com/qa5wq33 . For your convenience you can download a microfiche diagram for each spare part. Anyway the easiest way to do this is to loosen up this brake pad pin before you remove the caliper. Before you remove the brake pad pin, there's a retaining clip right here that you need to remove before you loosen it up. Just grab it with a pair of needle nose pliers and pull it out.
With that clip part removed, you can loosed up this brake pad pin. It just makes it easier. It's easier to do with the caliper still attached to your Road Glide. Now we can remove the brake caliper bolts and you're ready to lift the caliper off the bike. Never let the caliper hang from the brake hose because you can damage the hose so pre-plan where you're going to rest this before you pull it off. With the brake caliper off your Harley Road Glide I can now completely remove this brake pad pin. You can see how this brake pad pin extends through this caliper and goes through the brake pad. Here's one brake pad here and here's the other one and it holds it in place. Now I can remove this pin and remove it all the way and then I'm ready to turn this caliper over and work these pads out.
You want to be real careful when you're handling these brake pads. You don't want to get grease on the friction material. These are my brake pads. This part of the brake pad is the friction material. The metal backing plate is a metal backing plate that the friction material is attached to. The distance from the top of this metal backing plate to the top of this friction material is your brake pad thickness and like I said earlier, the minimum thickness for this brake is 16/1000 of an inch. These lines are wear indicator lines. As long as you can see these wear indicator lines, then you're above that 0.016 of an inch. If you can't see them anymore, then it's time to replace the pads.
Another way you can measure the thickness of this friction material is to use a pair of calipers. You want to extend this piece of the caliper and rest this part against the metal backing plate and then rest this part against the friction material like this and then press it down until that part rests against the friction material and then take a measurement. It's 0.073 of an inch and then we'll do the other one. The thickness of this one is 0.077 of an inch so I'm well away from that 0.016 of an inch minimum.
Along with measuring the thickness of the friction material, you can just inspect the integrity of the brake pad. The friction material should be relatively smooth. There shouldn't be any deep gauges, except for these wear indicator lines. The surface of this friction material should be relatively parallel to the metal backing plate, which shows the pad is wearing evenly.
Before you re-install the pads, there's a brake pad spring in there. Make sure that that's in place before you insert the pads. Now I'm ready to re-install the brake pad. Make sure it's resting against these caliper pistons so there's enough space between the pads for the brake disc. That way you don't have any problems re-installing the caliper. Kind of work it in here and like I said earlier, make sure you don't have any oil or grease on your hands because you don't want to get that on the friction material of the brake pad.
With the brake pads in place, I can re-install the brake pad pin and tighten that down. I'm not going to tighten it all the way because it's easier to tighten this when the caliper is attached to the bike. Now I can re-install the caliper on the Road Glide. Make sure that the brake disc fits in between the brake pads and re-install the caliper bolts. The caliper bolts should be tightened to between 43-48 foot pounds. I'm going to tighten them to 45 foot pounds. Now I'm ready to tighten the brake pad pin. The brake pad pin should be tightened between 75-102 inch pounds. I'm going to tighten it to 80 inch pounds.
Now I'm ready to re-install this retaining clip. The retaining clip just fits around the brake pad pin. With the brake caliper re-installed on the bike, I'm ready to re-install the right saddle bag and take the bike out for a test drive. Make sure that the brake system is working properly. Always take it easy until you're confident that everything is working correctly.
One thing I forgot to mention earlier, it's not a good idea to wash off your brakes before you work on them because you don't want to breathe any brake dust in. They used to manufacture brake pads using asbestos so the older the bike is, the more likely that the brake pads do have asbestos and you don't want to breathe that stuff into your lungs.
Thanks for reading!
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