Tech Tips: Replacing and Bleeding Brake Lines 2

Are your brakes feeling a bit mushy, or maybe you'd just like to upgrade their feel and performance? Check out this how-to on replacing your brake lines and bleeding them, with a little help from our friends at Galfer.

If you want to get your hands on some new brake lines, rotors, or pads; hit up Chaparral-Racing.com/Dirt-Bike-Brakes

For any other motorcycle parts, accessories, or gear needs, you can find them at Chaparral-Racing.com.

Transcribed version:

"Michael Lindsay: Hey, this is Michael Lindsay from Vital MX, we're here at Chaparral Motorsports today. We got the crew from Galfer and we're going over the removal and install of brake lines and how to properly bleed 'em to get the best performance outta your brakes.

Galfer Employee: I'm Chris with Galfer Braking Systems and this is Benny. And today we're gonna be doing an install on a front brake line on this RMZ 250. Some helpful tools to have. You're gonna need a torque wrench, set of sockets, some screwdrivers, some flare nut wrenches, and a brake bleeder if you have access to one. 

So the first step in getting your bike ready for installing the brake line, you wanna make sure you go ahead and level out the master cylinder. This is gonna help prevent fluid from getting all over the bike and it's gonna make the bleeding process a little bit easier for you. From there you wanna go ahead and remove the brake fluid from the stock system. You can remove the cap here on the master cylinder. Move down to the caliper, the bleeder port, and pull all the fluid out of the system. So we're gonna go ahead and loosen the bleeder on the caliper and we're gonna go ahead and suck the fluid out of the system. If you don't access to a vacuum bleeder, you can do the same thing with a small piece of hose and you can actually use the lever at the master cylinder to pump the fluid through the system. If you don't remove the fluid from the system, what you're gonna have is a bunch of fluid all over your shop floor. So this is gonna help save you from having a huge mess. 

Now that all the fluid's outta your system, you're can move up to the master cylinder and remove the factory banjo bolt. Now you're gonna need a hex wrench to do so. As you're pulling that off, what's also gonna be helpful once you get the line off is to put something like a small piece of paper towel through the actual banjo eyelet here. And that's just gonna prevent you from getting brake fluid on anything else on the bike. Just like that works fine. Next you're gonna be moving to the caliper. We're gonna go ahead and remove the factory banjo bolt here as well. Again, using the same hex wrench. Have some paper towels ready as when you remove this, you're gonna have a little bit of fluid coming out. And as with the top line, you wanna also put a piece of paper towel through the banjo eyelet at the bottom just to prevent fluid from coming out. The next step is gonna be to remove the factory clamp here on the fork guard. We've got two small hexes, it's a eight millimeter. And from there, we're now gonna move up a little bit here on the bike and you have a second clamp up at the lower triple clamp. 

So going to install the Galfer brake line, we're gonna start at the master cylinder. All of our Galfer brake lines are gonna include a label that shows which end is intended for the master cylinder, and it's gonna install in the stock orientation, so we have this banjo, it's gonna move away from the actual master cylinder. All of our Galfer brake lines are gonna include banjo bolts and the necessary crush washers for installation. We are gonna include two for each connection point, as well as two extras, so don't be alarmed if there's two extras in your kit. The banjo is gonna be installed with one washer against the nut and one against the master cylinder. You're gonna thread it in just like the factory line. At this point, you do wanna thread this in and get a snug fit, but you don't need to torque this. 

Next we're going to start fastening the OEM clamps, the first one at the lower triple clamp here. Just gonna use the factory clamp with the factory hardware. We're gonna install that, and then we're gonna move down to the fork guard. This will install with the factory fork guard clamp. Make sure that you have our stiffener positioned at the change in diameter in the clamp here. This is gonna look just like the factory setup. So next we're gonna move to the caliper, and we're gonna install the caliper banjo in the same factory orientation. It's gonna actually bend away from the caliper with the same configuration on bolts and washers we did up top. I just wanna gently thread that in. There's a little bit of tension on the line, so you wanna make sure you don't cross-thread that. It's very important that when you are actually attaching the banjo bolt to the caliper, you snug that bolt down. 

Moving up to the master cylinder, we're gonna go ahead and put some fluid in the master cylinder. This is really helpful if you have two people at this point as you start to begin the bleeding process. It can be done by one, but two makes everything a lot easier. Now this is a step that may or may not be necessary. I find it pretty helpful. At this point I'll actually crack the banjo bolt slightly loose, just about a quarter turn here at the master, and I'll push some fluid out of this orifice. You do that by pushing down on the lever, just in the same fashion that you'd bleed a brake, it's a down/up procedure. Hold that lever down. Snug that bolt. It doesn't have to be, again, tight or torqued, just snug enough. Release that lever, let it up. Then you're gonna go through that process again. And this is where it helps to have somebody. So you're gonna push down. I'm gonna tighten it. Go ahead and up. You only have to do this maybe two, three times. Down and up. That should be good. You just wanna make sure that you get some fluid out of the master cylinder, and this will help eliminate air bubbles in the system as you move down further in the system.

One important step from now through the rest of the bleeding process, you need to keep an eye on the master cylinder fluid level. You never want that to run dry. It's not the end of the world if it does, but you are gonna have to start bleeding process again from scratch if you do run that thing dry. So Benny's gonna make sure that we keep that fluid reservoir full. I'm gonna go ahead and crack the bleeder down here. Now, if you have the vacuum system available, this is very helpful at this point to remove any of the air. If you don't, it could be done with a standard gravity bleed process or a down/up procedure like we did a little bit earlier. So I'm gonna crack this loose. And we wanna get a flow of fluid. It won't necessarily be clean and clear, but you wanna see some fluid coming out of the caliper. So we're gonna continue doing this until we see that. So at this point, we're seeing some fluid starting to come out of the caliper. Wanna let that run for a few seconds here. We're gonna do a standard bleeding process regardless of what bleeding method you're using at the end to ensure that we have a good, steady flow of fluid. 

So we're gonna do a standard bleed on the system after the vacuum bleeding. The reason being that it's hard to tell if you're getting air and/or fluid out of the actual bleed hose. The vacuum bleeder sometimes can actually pull air through the system as well. So that's the reason that we kinda finish up with this step. So now we're gonna move up to the master cylinder, Benny's gonna help us. We're gonna give the lever a couple pumps. They don't have to be fast, they can be slow. And then you should start to feel a little bit of pressure at the master cylinder here. If you don't have any kind of pressure whatsoever, you might wanna go back down to the caliper and bleed it a little bit further. But from here, he's gonna hold the lever down in the same process we used on the banjo bolt, I'm gonna open the bleeder on the caliper and we're gonna release some of that fluid and air. I'm gonna let Benny know when I have that bleeder tightened back up. I'm gonna say, "Okay, you can go ahead and release." He'll release the lever and he'll go ahead and give it a couple more pumps. And we're gonna repeat this process two, three, maybe four times. You should feel a slow improvement in the brake lever, and the level of the lever should come up a little bit. So go ahead and hold that down. Up and a couple pumps, down, up, go ahead and give it a couple pumps, hold it down, up. 

So now that you have a good bleed on the system, have a nice, firm lever here, we're gonna go through, we wanna tidy everything up. We're gonna go through the banjo bolts. Wanna make sure these are torqued to spec. Our spec for anything that's silver or gold fittings is gonna be between 15 and 17-foot pounds. Anything that's anodized aluminum, red, black, or blue, it's gonna be 12 to 15-foot pounds. Wanna use an appropriate torque wrench on those. Once you get that finished, we're gonna put the master cylinder reservoir cap on. Usually want the fluid topped off to about three-quarters of the way full. That's sufficient. And have some rags underneath in case you just spill a little bit of fluid so it doesn't get on the bike. We do include two extra crush washers with all of our Galfer brake line kits in the event that you have to remove one of those connection points during the installation process. Keep in mind those are single use only. So you don't wanna reuse them. If you have any questions doing the install, feel free to give our tech department a call at any time. And we appreciate you considering Galfer products for your motorcycle. Thank you."

Credit: Joe Carlino

C50_profile_1424660203 ML512 1/13/2016 7:03 PM

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