Tuesday, September 23, 2008

Coffee Mate

Care and Bleeding of your Fullthrottleinc hand brake ·Don't hook up the cable until you're done bleeding the h.b. ·Regardless of where you are going to mount the h.b. master, place it somewhere high while bleeding it so it's the highest point in the brake system.
·Hook up one line at a time! Remove the stock rear brake line entirely and attach the shortest of the two included brake lines to the rear master cylinder. Take the cap off of the rear reservoir and make sure it's full. Keep an eye on it, you don't want to get half way through the job and run dry because you'll be right back to square one. With your thumb and finger (where latex gloves if you can, brake fluid is nasty) over the end of the brake line, begin slowly pumping the rear brake pedal. Soon the pedal will be pumping all of the air out of the line and will be pumping fluid up to the end. Once you can feel fluid pressure against your fingers, don't push the pedal hard enough to push fluid past your fingers, but continue to lightly pump it. These pulses will coninue
to move the smaller air bubbles towards the end of the line that you are holding up in the air. As the smaller air bubbles reach your fingers the will pop past them. You know you are done when even the slightest movement of the brake pedal will force fluid past your fingers. If you can still move it and hold the fluid back you've got air somewhere. Get a feel for this and you'll
have no trouble bleeding the rest of the brake system. So now that the air has been purged from the line running to the rear master cylinder, attach the end to the h.b. master. This line attaches to the hole closest to the bottom. It is your input line. Now that the first line is attached, place your finger over the out put hole and purge the air out of the h.b. master just like
you did the first line, continuing to use the foot pedal as your pump. When it is solid with fluid, attach the longer of the two brake lines to the hole closest to the top and hold it up in the
air above the master cylinder. Purge the air out of it and route it to the rear caliper. After it's routed, hold it up as high as you can back there and hit that brake pedal a few more times to
get rid of any air you might of acquired during the few moments your were routing it. Once it's solid, attach it to the rear caliper. Without missing a beat, pump up the brake pedal
to build pressure in the system and crack the bleeder a few times to burp out any air that is in there. .........So your lines have been run and the rear brake doesn't feel so solid. That's normal. It's hard to hook up brake lines and not get some air in there while doing so. With the brake system pumped up, go through and crack the bleeders again. You say it's still not perfect? You should have enough pressure at this point that after cleaning the fluid off of the rear rotor you have enough back brake pressure to ride. So do it. Secure your lines, make sure you aren't binding up when you turn the bars and have a good routing so that when you turn the bars you aren't excessively pulling the brake lines (it's good to run them as closely as possible to the frame neck and leave a little excess for a loop at the h.b. so you are just taking a little slack out of the loop instead of pulling on the brake lines). If you routed them right they run uphill most of the way to the h.b. Now go for a ride. The vibration of the motorcycle will help migrate the mini air bubbles to them out when you get back. Hit balance point a few times, it's hard for the air to go anywhere but to the h.b. master when it's that high up in the air. Now that you are back and you've cracked the bleeder on the h.b. a couple times with only solid fluid coming out you should be good. Your rear brake should feel fantastic. Go ahead and attach your h.b. cable and figure out how you want to position your levers. If you have a turnsignal box on your clip on it's time to get creative and put it somewhere else. Your best bet will be to put the h.b furthest inboard toward the bike and run a short clutch lever to the left of it. Cut your levers so you can use your index finger on the clutch and your middle finger on the h.b. Put the h.b. cable on one of the first two settings (closest to the piston) while you get use to it. You may still have the slightest bit of air in your system that after a few more rides will work it's way up to the h.b. master so you can burp it out at the bleeder. ·This is BIG!! When you step on the brake, the arm on the bottom of the h.b. master cylinder is pushed out to it's home position. There is a mechanical stop inside the master cylinder that it is pushed up against. You need a minor amount of slack in your h.b. cable or the cable will prevent the arm from moving all the way to the home position. The cable is very strong. It has been tested to over 500 pounds tensile strength. You will not break it with the strength of your hand no matter who you are. However, if the cable has to endure the stress of all the pressure you can create with the rear brake pedal because you don't have enough slack in the line to let the h.b. lever extend out to it's rest position, I promise the cable will eventually snap. On top of that, until it does snap your rear brake will not feel firm or responsive because the energy it is creating is being used to stretch a cable and compress a cable housing instead of building pressure against the rear caliper piston. It will also prevent the h.b. master cylinder from releasing pressure from the rear caliper, rewarding you with cooked brake fluid, a warped/cracked/glazed rear rotor and a garbage session. The best way to ensure that you have adequate slack in the cable is to step on the brake pedal and move the exposed cable (between the lever and master cylinder body) from side to side. If it feels tight when you try to push it to the side, the cable is too tight. Now, with your foot still on the rear pedal, feel your brake lever on the handle bar. Can you move it even slightly? You don't want to be able to flop it
back and forth an 1/8 of an inch or more because it would fees sloppy,
but if it is so tight it doesn't move at all than the cable is too tight. The
slightest bit of freeplay is enough, none is too tight. When bleeding the handbrake, make your first priority to get the rear brake feeling as solid as possible. When the rear brake is golden the
handbrake will be too. So you've got a long length of brake line and a h.b. master in the middle
that is filled with air and you've got to replace all that air with brake fluid. What is the easiest way to do it? Be creative. If something you are doing isn't working, don't keep doing it and expect results. Try another approach. Remember, air goes up and it clings to sharp edges. When in doubt, keep it simple. Don’t over think it. If you hear air in it, than there is still a little air in the system. Nothing is leaking or “sucking air in. I’m almost never able to get something perfectly bled in the shop. I generally have to bleed it, ride some, go back over things, and ride some more. Usually after a few hours of riding and going over the system my brake is fantastic and I don’t have to touch it for the rest of the season unless I slip up and do something carelessly when changing brake pads. Remember to flush your fluid once in a while because over time your brake system absorbs moisture from the atmosphere. This moisture lowers the boiling point of the fluid and if you really heat things up it will boil and become steam.

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