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| THE PFM BRAKE SYSTEM: by
Two Brothers Racing by Marty Kane Friday, December 17, 2004
If you are like me... you are doing it aboard a bike which is quite frankly too damn fast anyway... In my case, it's Suzuki's famed Hayabusa... a bike which runs into the nines, and is capable of blipping towards 200 MPH anytime you so desire. Remarkably... Suzuki made this bike a work of engineering art... It's so finely tuned, that a full header system is only worth a few horsepower, it's so radical that at any RPM it can produce blistering performance, but it's equipped from the factory with brakes which were originally designed for 750cc motorcycles... why? My bike clearly weighs in over 500 pounds, a GSX-R750 is 400 pounds or less... am I missing something here?
The very first time I approached 175 MPH on the bike, it amazed me how quickly I could get there. After holding it there for a short while, I ran upon a toll booth ahead, and that's where it got exciting. I remember yelling to myself (inside my helmet), yeeha... hold on Nellie... Well, I almost skidded to a stop after having ample shutdown space and not enough brake power to go around! After looking for parts for this two wheel rocket, I realized that the drag racing community has nothing on the road racing crowd as far as high tech sportbike parts. One glance at a factory prepared Superbike will illustrate that and afterwards you will understand how far in the dark ages we just might be! The bikes we ride on the street, and the bikes that many are taking to the track these days, are no longer old KZ's and GS's, they are not necessarily full blown dragbikes, they are stock or modified sportbikes purchased off the showroom floor in the past few years. As the result, bolting on old drag race technology is not possible in some cases, and in others it makes no sense. After my first attempt of slowing down from speed... I realized that I needed help. After watching the road race community slam in and out of turns, applying brake power constantly and swiftly each time, I asked Two Brothers Racing owner Craig Erion for some advice. His response was simply to smile and chuckle... knowing already that a good brake system is what make riding more enjoyable. "The first time you ride a bike with good brakes, you will never go back" he said.
Since his past includes a successful factory racing effort, I figured he had enough background and knowledge to be somewhat of an expert, and I took his advice to heart. He walked into his warehouse, and came back out with a set of PFM "GP style" brakes. These brakes are manufactured in Europe, and are used on almost every professional road race bike in every series. After looking at the parts, I thought he was crazy quite frankly... because the rotor surface area is actually narrower then that of a stock rotor. He explained that composition of the Ferodo racing pad, in conjunction with the 320mm rotor and the clamping force offered by the PFM six piston caliper design, were actually a better combination and I would not be disappointed. From a drag racers point of view, the rotor is something radical in itself. It is a laminar ring design, which in simple terms means that there are two working parts to the rotor; the carrier and the friction disc. The friction disc rotates in a 360 degree track on the carrier, and a circular (or laminar) clip holds it in place. There is always equal contact and always equal pressure on all parts. No binding can occur, and over time nothing wears out... because all parts have equal contact. Many aftermarket rotors actually tend to add floating buttons to distribute the load more effectively, and this simply causes more chance for failure. One brake system I looked at actually had thirteen, and when I asked the manufacturer how long they last on the street... they chuckled and told me these are parts intended for racing, and do require periodic service. Am I missing something here? Another issue with the rotor is the material used. The carrier should not warp or bend over time, and the friction surface needs to be durable enough not to gald or wear out quickly. Something else to consider... is that pads are not all equal. The rotor and pad have to be perfectly matched in material and composition... or they will not reach maximum braking power together! Two Brothers has addressed all of these issues perfectly it seems, because after running 5,000+ miles on them, there is no major wear on the rotor, and the carrier checks in with less then .005" run out. Honestly, the cast steel rotor surface is amazingly perfect considering I'm almost through my first set of pads, and I use my front brakes solely while riding stoplight to stoplight! The PFM six piston calipers are works of art. Machined from billet aluminum, and then finished with a durable black hard anodize coating, they have more clamping power then you could probably use!
Considering my Hayabusa tips the scales at about 700 pounds with rider aboard, with the stock brakes up front, you could not even skid the front tire if you applied too much brake in most circumstances. Now, you can easily run a stoppie into the ground from any speed! My first trip up our local 8,500' mountain road (Angeles
Crest Highway), I learned first hand what Craig tried to tell me. A good brake system does
make the difference. It took no effort to slow the bike down while bombing downhill into a
radical turn at over 100 MPH. We are not talking about front tire screeching... out of
control slowing of the bike, I am talking about perfect on-demand brake control, which
allowed me to Craig personally walked me through installation, and even without him, the whole process would not have taken more then about two hours... and required only simple hand tools. Going from standard racing protocol, I wanted to flush the system and start over with silicone-based DOT-5 brake fluid. Craig proved to me how ignorant I was to brake system technology, as he explained that silicone fluid by design does not mix with water. Since any hydraulic system will gain water over time, that is bad... and over time can bite you. He illustrated the benefit of DOT-4 fluid by showing me how dark my stock fluid had become. He explained further that the darkness is a built in warning system, and is the fluid's way of telling you it has gained and mixed with water... and needs to be changed.
One thing I must warn you about at this point, is a matter of safety. Those fancy lightweight bolts that the factory uses to hold the calipers and brackets to the front end are intended for one-time use. Anytime you remove the calipers (even for servicing), you should replace them! After this, I am now a believer in good brakes... The first time you travel down the highway with them, you will feel a renewed confidence when a car approaches your drive path. Using these Two Brothers PFM brakes, I can stop in time... I know that, and I ride with more confidence and better piece of mind! You will also save a few pounds of
front end weight... which is a good thing, From personal experience... I can tell you how much of a problem a car could be when it pulls out in front of you. If you've got those cool lightweight drag race brakes installed on your bike, you might have a problem. BAD BRAKES CAUSE BIG PROBLEMS! I use to have this really cool turbocharged Pro Street Kawasaki, which I rode on the street everywhere, and every day. Once, while making a high speed "test pass" on a local boulevard (one of my more stupid moments, I assure you), I plugged myself into the back of a Honda Accord after it pulled out from a driveway near the end of my run. I grabbed every bit of brake I had... but the bike failed to stop in time, and after 1 1/2 years of recovery, the total loss of a $40,000 bike, and over $250,000 worth of medical expenses... I wish I could turn back time.
Two Brothers Racing has taken guesswork out of brake system purchasing, by putting together brake kits for almost every sportbike in production today. Their kit comes with two PFM calipers, featuring GP-style quick release pins to facilitate quick changing of the pads without disassembly; two 320mm narrow blade, full floating rotors, which bolt right up to the wheel without modification or adapters; a set of Ferodo racing brake pads; and two PFM brake stainless steel brake lines... which do not expand under pressure and provide a better feel and accurate brake control. They stock kits for Honda VTR & CBR models, Kawasaki ZX, Suzuki GSXR and TLR, Yamaha YZF, Triumph, Ducati and others. CLICK HERE TO REQUEST INFO VIA A READER SERVICE CARD!! For more information, contact: Two Brothers Racing,
Inc. |
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So...
if you are like the average bike enthusiast, you've got a sportbike or two in your garage,
you ride whenever time permits on the highway for fun... and from time to time you get in
over your head by running 100 or so MPH over the speed limit.
He explained the benefits of
aftermarket brakes, and told me about his companies search through the years. 
drive faster
and deeper into the turn, and then slow at the right time to accelerate through the turn
properly.
He also taught
me a little about bleeding brakes, and by using proper tools... showed me how quick and
easy it should be.
