Front Brakes: Single Disc VS Dual Discs

[Bud]

Everything I've read about the brakes on the NT700V has been very positive. When Honda designed the brakes for it I think they did a very good job. The front brake on the NC700X is a single disc brake. I am not an engineer and don't know a great deal about brakes, but I feel a bike with duel discs front brakes has more stopping power than a bike with single disc front brakes. Do any of you have any thoughts you would like to share with me on this?
Bud

 

[MaggieMan]

Re: Front Brakes: Single Disc VS Duel Discs

but I feel a bike with duel discs front brakes has more stopping power than a bike with single disc front brakes.
Bud

I'm not an engineer, a designer or even a very good mechanic, so my opinion is worth exactly what I charge for it! You are right ... in a sense. A braking system transforms the wheels rotational energy and hence forward momentum of the bike by turning it into heat through friction. Brakes fade with excess heat. Do a lot of extreme braking in a short time and the heat builds up and the brakes fade more and more.

The advantage of a dual disc system is with (presumably) both brakes doing equal work, each only needs to generate 1/2 the heat that an, all things being equal, single disc system would. So in that sense, no, a dual-disc system won't have "more stopping power" than an equivalent single-disc system, but it will be much less prone to brake fade.

There is, generally, a weight and price penalty for dual-disc systems too, as you need two of everything, even though a dual-disc systems components are somewhat smaller than an equivalent single disc. However, there is also the safety redundancy if one disc should fail.

Scott

 

[JQL]

There is also the weight issue. The lighter the vehicle the smaller the brakes need to be to have the same effect.

 

[RedLdr1]

Single versus dual discs is also a co$t issue, which is probably the deciding factor in this case. The NC is supposed to be a economical entry level bike, hence one disc brake...

 

[DirtFlier]

[Single disc versus dual discs is cost issue, which is probably the deciding factor in this case..."] Another point is that the NC is 98 pounds lighter than a NT and that's significant. Too much front brake on a fairly light bike can lead to situations where you get a very close look at the blackup!

 

[loonytuna]

I'm no engineer, but I have been riding more than 40 years and I know this.

When I grab that front brake, the bike stops! And it stops really well, with just me or my wife and I.

I guess, if it works .....

 

[Rmcapozzi]

All things equal, yes, I believe looping off one set of rotor/calipers off the front end would result in less stopping power. But the NC isn't the same as the NT so it is not possible to compare braking performance only by the number of front rotors. At nearly 100 lbs less than the NT, I bet a single front rotor would be plenty. The NC rotors are also bigger rotors than the NTs (320mm vs. 296mm). I have a bike that weighs about 125lbs less than the NT and it has a single front disc. That bike has plenty of power to lift the rear wheel and flip you over the bars. It stops just fine.

 

[suvcw04]

I have a 2009 Yamaha Majesty 400cc scooter as well as the NT. The Majesty has one front rotor. I can tell you that the difference in braking, especially two-up is EXTREMELY NOTICEABLE!! The NT will STOP!!!! The Majesty will stop, but there is a world of difference in the pressure you have to put on the brake lever, and in the feel from the bike. If they could talk, the NT would say, "Hang on, I'm stopping RIGHT NOW." The Yamaha would say, "Yah, yah, as soon as I get to it."

 

[karl]

brakes transfer kinetic energy (your forward motion) to Heat. The added swept area of the dual disk system allows it to dissipate more heat allowing you to attack the corners in your favorite twisties without overheating your brakes. (overheating results in reduced stopping power) All the stock systems sold will lock the front wheel once. how long you can keep it up is the difference.

Not that sporting? Well they also add unsprung weight, complexity and cost... enjoy your ride.

 

[Rich]

One thing I've noticed on some single-disk front brakes is that it can produce a rotational force in the steering, as the drag of the rotor against the pads pulls forward on the fork leg on which the calipers are mounted. This is mostly prevalent when the caliper is mounted in FRONT of the fork leg, rather than behind. This is less noticeable if the rotor is on the right side and you apply the front brake lever. It's also less pronounced when the difference between the forks is small (i.e., narrower front tire). One example I can think of where this was very pronounced is the early Honda CB750. Single rotor on the left fork. Hauling on the front brake required counterforce on the handlebars to keep it straight.

Quirks like this get to where they are no longer noticed by the guy that drives it every day. But I borrowed such a 750 from my friend one day and it was really apparent to me.

 

[charlie b]

It is apparent on my Moto Guzzi as well. Lever works on front right disk. Foot works on left front and rear. You can feel the bike torque a little depending on which you are leaning on the hardest.

Like above noted, dual disks are really there for multiple, fast stops/slowdowns. A single disk properly designed can lock up the front wheel just fine As can a drum brake.

And a dual disk does not mean ease of pulling on the lever. My older Guzzi takes a LOT of pressure to operate the brakes. It is one reason I like having ABS on the Honda. Guzzi takes three fingers for a really hard stop. The Honda takes one.

The brakes on the Honda are really nice as far as I'm concerned.