"BRAKES"

THIS MONTH WE'RE GOING TO GET INTO THE BALANCE BAR ON YOUR BRAKING SYSTEM. WHILE THE BALANCE BAR IS NOT A CURE FOR A POORLY DESIGNED BRAKING SYSTEM OR A BAD SET UP ON YOUR RACER IT IS A VERY IMPORTANT PIECE OF THE PUZZLE.

TO PUT IT IN VERY SIMPLE TERMS THE BALANCE BAR IS A PART THAT CONNECTS TWO MASTER CYLINDER TO ONE PEDAL. HERE IS PHOTO OF A BALANCE BAR AS IT WOULD APPEAR REMOVED FROM A PEDDLE ASSEMBLY.

THE FOLLOWING IS A DIAGRAM BREAKDOWN OF THE BAR.

AND HERE IT IS INSTALLED  ON A PEDAL ASSEMBLY.

AS YOU CAN SEE IT IS NOTHING MORE THAN A PIECE OF THREAD ROD WITH A BALL BEARING SECURED IN THE MIDDLE OF IT. THE BEARING IS SECURED BY CLIPS INSIDE A PIECE OF TUBING THAT IS HOUSED INSIDE A SLEEVE THAT GOES THROUGH THE BRAKE PEDAL ITSELF.

WHEN YOU SCREW THE BAR ONE WAY OR THE OTHER THE BEARING IS MOVED CLOSER TO ONE CLEVIS AND AWAY FROM THE OTHER CLEVIS. THIS ADJUSTS THE  BRAKE BIAS BY APPLYING MORE PRESSURE TO ONE MASTER CYLINDER OVER THE OTHER. THE CLEVIS THAT THE BEARING IS CLOSEST TO GETS MORE PRESSURE THAN THE OTHER. SO FOR EXAMPLE LET'S SAY THAT IF YOU HAVE THE BAR CENTERED THE AMOUNT OF PRESSURE WOULD BE 50% / 50%. IF YOU MOVE THE BALL TOWARDS THE LEFT MASTER CYLINDER THAT MASTER CYLINDER WOULD RECEIVE MORE OF THE APPLIED PRESSURE THAN THE RIGHT CYLINDER, SAY, 60% / 40%. I KNOW THAT THIS DOESN'T REALLY MEAN MUCH TO YOU AT THIS POINT IN TIME BUT HANG IN THERE. LET'S PUT THIS TO SOME REAL WORLD APPLICATION.

FOR MY EXAMPLE I'M GOING TO TAKE OUT THE FACTORS OF BRAKE CALIPER PISTON SIZES, MASTER CYLINDER BORE SIZES, AND TIRE STAGGER. THAT'S A WHOLE SUBJECT ON IT'S OWN. SO ON OUR EXAMPLE CAR WE WILL USE x" BORE MASTER CYLINDERS, CALIPERS WITH x" PISTONS, AND TIRES WITH x" ROLLOUT ON ALL 4 CORNER. OK, HERE WE GO.

EVER NOTICED WHEN YOU GO OUT FOR HOT LAPS AND THE TRACK IS STILL KIND OF WET THAT WHEN YOU GET ON THE BRAKES THE CAR TAKES OFF FOR THE FENCE OR THE BACK COMES AROUND AND LEAVES YOU STARING RIGHT AT THE ONCOMING CARS? YEAH, ME EITHER  BUT I'VE HEARD ABOUT IT :). THIS IS A PRIME EXAMPLE OF IMPROPER BRAKE BIAS. IT WILL ALWAYS BE MORE PRONOUNCED AT EXTREME TRACK CONDITIONS FOR EXAMPLE SLOPPY WET DURING HOT LAPS OR DRY DURING FEATURE. BEFORE SOMEONE GOES OFF ON A RAGE YES THERE ARE MANY OTHER FACTORS THAT GO INTO HOW A CAR HANDLES BUT I'M TALKING ABOUT THE WAY THE CAR REACTS AT THE MOMENT OF  APPLIED BRAKE PRESSURE NOT AS YOU YANK ON THE WHEEL AND START TO TURN INTO THE CORNER.

OK LET'S DO SOME REAL WORLD EXAMPLES AND CORRECT THE SITUATION BY ADJUSTING THE BALANCE BAR. THE FIRST THING YOU HAVE TO UNDERSTAND IS THAT THE BRAKES THAT RECEIVE THE MOST PRESSURE ARE THE ONES THAT SLIDE. SO IF YOU TAKE THE HOT LAP SITUATION DESCRIBED IN THE PREVIOUS PARAGRAPH YOU WOULD COME TO THE CONCLUSION THAT WHEN YOU WERE HEADED FOR THE FENCE THE FRONT BRAKES RECEIVED MORE PRESSURE THAN THE REARS AND WHEN YOU TURNED IT AROUND THE REARS RECEIVED MORE PRESSURE THAN THE FRONTS. SOME PEOPLE LIKE TO USE THE WORD "LOCK" THE BRAKES BUT THAT IS A MISLEADING TERM. GOOD DRIVERS WITH GOOD BRAKES SELDOM "LOCK" THE BRAKES. ONCE A BRAKE IS "LOCKED" IT HAS LOST AVAILABLE TRACTION AND IS DEPENDING ON FRICTION. YOU HAVE TO KEEP THE WHEELS ROLLING TO GO FAST!  SO HOW DO YOU ADJUST THE BALANCE BAR TO CORRECT THESE HANDLING NASTIES? LET'S START WITH THE HEADED FOR THE FENCE EXAMPLE SINCE THIS IS THE ONE YOU'LL SEE THE MOST DURING HOT LAPS. TO CORRECT THIS YOU ARE GOING TO HAVE TO SHIFT THE BIAS TO THE REAR TO GET THE REAR TO COME AROUND. AS I SAID EARLIER THE MASTER CYLINDER THAT THE BALL IN THE BAR IS CLOSEST TO RECEIVES MORE PRESSURE. SO YOU WANT TO ADJUST THE BAR TOWARDS THE MASTER CYLINDER USED FOR THE REAR BRAKES. FOR THE LOOKING AT THE PACK COMING STRAIGHT AT YOU YOU WANT TO ADJUST THE BAR THE OTHER WAY SO YOU GET MORE FRONT PRESSURE AND LESS REAR. HOPE THIS HAS MADE SENSE. IF YOU HAVE ANY QUESTIONS YOU CAN ALWAYS DROP ME AN EMAIL ON THE SUBJECT.

NOW HERE'S A TIP FOR YOU. AT ONE TIME OR ANOTHER EVERYONE HAS USED THE RIGHTY TIGHTY, LEFTY LOOSEY PHRASE. I'VE FOUND THAT WHEN YOU INSTALL YOUR MASTER CYLINDERS INSTALL THEM SO THAT WHEN YOU TURN THE BALANCE BAR ADJUSTER TO THE RIGHT YOU ARE TIGHTENING UP THE CAR (MORE  FRONT BRAKE) AND WHEN YOU TURN IT TO THE LEFT YOU ARE LOOSENING UP THE CAR (MORE REAR BRAKE). FOR ME IT MAKES ONE LESS THING TO THINK ABOUT IN THE HEAT OF A BATTLE. ALSO WHEN MAKING ADJUSTMENTS MAKE SMALL ONES AT A TIME UNTIL YOU GET USED TO WHAT IT TAKES FOR YOUR CAR. SOMETHING ELSE IS PRE-ADJUSTING THE BRAKES BEFORE YOU GO OUT. FOR MOST CASES I CENTER MY BAR AND THEN GO A TURN OR TWO TO THE REAR FOR HOT LAPS. WHEN I GET BACK INTO THE PITS I TAKE IT BACK TO THE CENTERED POSITION FOR THE HEAT RACE. AFTER THAT I KEEP AN EYE ON THE TRACK FOR THE FEATURE. IF IT'S GETTING DRY SLICK I'LL GIVE THE BAR A TURN OR TWO TO THE FRONT BRAKES, IF IT LOOKS LIKE THE TRACK'S HOLDING TOGETHER OR GETTING TACKIER I USUALLY DON'T DO ANYTHING AFTER THE HEATS, I WAIT AND MAKE ANY NEEDED ADJUSTMENTS ON THE FLY FOR THE FEATURE. BY PRE-ADJUSTING THE BRAKES YOU'LL BE CLOSER TO THE OPTIMUM SET UP. IF YOU ARE OFF A BIT YOU CAN LIVE WITH IT OR MAKE A SMALL ADJUSTMENT INSTEAD OF CRANKING ON THE BALANCE BAR LIKE YOUR DOLLYING A TRAILER!

HOPE THIS HAS HELPED. LIKE I'VE ALWAYS SAID, "I CAN'T TELL YA WHAT TO DO BUT I SURE CAN TELL YA WHAT NOT TO DO!!!

FOR MORE INFO ON BALANCE GO TO

http://www.tiltonbrake.com/pdfs/28.pdf

OR

http://www.wilwood.com/Products/005-PedalAssemblies/Pages/techtip/pedaltech.asp

BOTH OF THESE SITES HAVE BEEN VERY HELPFUL TO ME IN THE PAST AND CONTAIN WAY MORE INFO THAN I HAVE PROVIDED!!!

THE NEXT BRAKING AREA I'LL DISCUSS WILL BE THE USE OF INLINE PROPORTIONING VALVES TO GET YOUR RACER HANDLING BETTER, SEE YA LATER!!

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