How Much Better are Dual Front Discs vs. Single?

Z1109R Fin wrote:

OK, I do understand that if you want to keep you bike as stock as possible then you might want to stay with one disc. Dual disc is more efficient and adding 2 or 4 -piston calibers makes braking even more effective.

I do not understand any argumentation that " too powerfull brakes cause accidebntal dips":huh: Come on now, I´d rather dip it that fly through a windscreen!

The point made was that the stock brakes (single disc) have a proportional amount of braking for a given pressure. A light pull gives a light brake and a hard pull puts my face in the windshield. There is no advantage to having a brake system that locks the wheel with a light pull, it effectively moves system operation towards digital (on/off) instead of an analog one (proportional). I'd rather have the brake work like it does now. I have enough brake power to lock the wheel, I can't use any more than that.

As for panic stops..... practice them all you want, but if there is a truly life threatening situation, 99.999% of people will yank hard on the brake. That's why ABS systems were developed, I wish they had them on bikes. I don't want a hair trigger front brake.

Bountyhunter wrote: "That's why ABS systems were developed, I wish they had them on bikes."

Actually a number of new bikes do have ABS. It's probably just a matter of time before someone retrofits them onto a KZ. Ed

antilock brakes suck on cars ,i cant imagine them on a bike! :S

Bluemeanie wrote:

I have to stick up for the single disc. I've ridden both and IMO my larger single disc stops as hard as the smaller duals. Just my .02

i never heard of differant diameter rotors for single versus dual discs dual disc rotors are normally thinner to compensate .and yes they stop much better in my experiance,not to mention they help hold the frontend down on overpowered wheelie monsters! :laugh:

Some dual disk rotors are smaller in diameter.
The KZ650-CSR has an 11" single rotor.
The KZ750-Ltd-4 has smaller disks.
Those two bikes are very similar to each other.

PLUMMEN wrote:

antilock brakes suck on cars

They've saved my ass a few times. I remember one particular instance going about 60 on an expressway approaching an intersection when some major brain dead dipwipe sitting in the left turn lane at the light decided to pull out into my lane right in front of me so he could go straight. I couldn't go around on either side because of solid traffic. I was so sure I was going to hit him, I had already braced for impact as I held the brakes full down. Amazing how much faster cars stop with ABS.

JMKZHI wrote:

Some dual disk rotors are smaller in diameter.

The ones I have seen all are. The point is to reduce the mass and still get better heat resistance. With dual discs, you have far more surface disk area exposed to the airflow so the heat can transfer into the air more easily. That's why dual disks are superior for fade resistance.

Dual rotors split the amount of heat generated by braking over two rotors, lowering the temperature of your brakes. Then, as mentioned the extra surface area allows the brakes to cool faster as well.

This prevents brake fade because you are not melting pads, cooking rotors, or other bad things.

PLUMMEN wrote:

antilock brakes suck on cars ,i cant imagine them on a bike! :S

I'm glad someone else feels this way. Apparently that makes 2 of us anyway. On the Honda GL1800 forum this subject comes up regularly and as the GL1800 can be bought with or without ABS opinions vary. 95% believe heavily in ABS. I bought my GL1800 specifically without solely on my own experience in cars in trucks. In 1989 I bought a new Ford truck with ABS. It nearly killed me several times because all the ABS did in it was basically remove all brake pressure the instant wheels even think of locking. So the scenerio is you're going 40mph on a wet road, a quick stop is needed for a stoplight, dog, another car, or any other of 10,000 reasons, hit the brakes and the truck instantly brakes as I'm used to for 40 years, then I feel the brakes are locking so I let up pressure slightly, BUT, the ABS also kicks in and completely releases the brakes. Whoa, now I'm not stopping, jam the brakes on full trying to forget all skills learned in 40 yrs driving and finally stop, with any luck before hitting whatever was the object you were avoiding. Cut the wiring to the ABS and warning indicator on the dash and voila' perfect brakes. 8 yrs later I get a new Ford truck and back to this crap ABS problem, but on this truck they use the same sensor for the ABS as they do to do the speedo, so wiring can't be cut, so I'm out of luck. I've driven this truck 13 yrs now and I just can't believe I'm still alive. Give 1/4 mile following distance is my advice, keep eyes peeled and be ready. Of course these are only 2 wheel ABS, so the wife gets a new Jeep with ABS. We test the ABS a few times. What it does is if the wheels are locking it pumps the brakes like 10 times a second or whatever, so you get this d-d-d-d-d-d-d feel like a machine gun. We were on a dirt road, I took a turn, the ABS kicked in and that d-d-d-d-d-d made the wheels hop with every d-d-d- just like a washboard road and I had no brakes and we nearly went off the road. Do I want this on a motorcycle?

RonKZ650 wrote:

PLUMMEN wrote:

antilock brakes suck on cars ,i cant imagine them on a bike! :S

I'm glad someone else feels this way. Apparently that makes 2 of us anyway.

Make that 3

Four

The Bosch system on BMW automobiles works perfectly, in my opinion. Each wheel is independently controlled from locking. The system modulates off and on at a relative high frequency so that the contol is very smooth. If you press too hard on the pedal the system smoothly does its job. If you ease up it quietly goes back to sleep with no abrupt action ever.

Works well on dry pavement, and has kept me out of trouble numerous times in the rain. And on snow and ice, it is fun to just play with the car on an empty parking lot. You simply cannot lock the wheels. Good clean fun.