06 unified brake system (again)

[Fencer]

I posted this once before and it turned into an I do/don't like ABS. Lets not go there this time.

I was cleaning up and filing some stuff when I came across my 06 sales brocher so I decided to re-read it to see if I got the marketing hype. I came across a Typo? maybe?

As per the last topic. The final word was the front brakes are not linked to the rear at all and the rear link to two of the front calipers. Per Yamaha's website

"Standard equipment Unified Braking System w/ABS: The front brake lever activates six of the eight front braking pistons; the rear brake pedal activates the rear piston and the remaining two front pistons, for balanced anti-lock braking in all conditions."

[SIZE=12pt]BUT...[/SIZE]

The printed book reads,

"Combined ABS. Now the front brake lever operates six of the eight pistons in the front calipers AND TWO OF THE FOUR IN THE REAR, while the rear pedal activates the REMAINING two front pistons ALONG with the other two in the rear caliper - for optimun braking balance."

Now I know why I posted the first topic to begin with. I felt the back tire should not roll with the front brake applied.

Is this another case of redlining at 20,000 rpms?

On the 05 with ABS is there ANY linkage front to back?

Will someone with an 06 centerstand it, grab the front brake, and check for movement on the rear?

 

[FJRottie]

Interesting. All printed info on websites was, the front only activated the front.

When the front brake is applied, all 4 - LHS front caliper pistons are activated, while only the "upper" two pistons on the RHS front caliper are activated. When applying the rear brake, both rear caliper pistons are activated plus the two lower pistons on the front RHS caliper are activated.

Someone with an 06 should try it on the center stand like you said.

 

[FJRocket]

OH NO, Say it AIN'T SO! You mean I can't lock the front and smoke the back tire on my '06? :angry:

Not that I've ever done that before, mostly because I can barely touch the ground on my '04. But it sure looks cool when Smitty does it.

All right, you '06 owners, get out there and test that front brake lever and let us know the truth!

 

[v65]

Mine spun no problem, so unless they have some complicated, the bike has to be on, electronic linkage the rear is not linked to the front. I would have smoked the rear for you just to make sure, but it only has 2600 miles on it. Give me a couple of months

 

[Warchild]

This has to be a typo.... to my knowledge, we still only have two pistons on the rear caliper.

 

[Constant Mesh]

Actually there is only one piston in the rear caliper. If you look at the left side of the caliper you'll only see a brake pad -- no hydraulic piston.

 

[Warchild]

Actually there is only one piston in the rear caliper. If you look at the left side of the caliper you'll only see a brake pad -- no hydraulic piston.

Yes, that is indeed correct. My bad...

 

[flyinlow]

The second method you describe is how the linked brakes work on my Honda VFR. The FJR front brake does not operate the rear brake. Comparing the two brake systems, you would have to see a mini master cylinder on the front brake on the FJR to operate the rear brake, which of course it doesn't have.

 

[rcan08]

acording to the manual page 1-4 and the block diagram, when the front lever is pulled both sets of pistons in the left front caliper are operated, but only one set of pistons in the right front caliper is operated.

And when the pedal is depressed the rear brake caliper and one set of pistons in the right front caliper are operated.

 

[tyronewildman]

An easy way to see if a brake is linked (one pedal or lever operates part of both front & rear) is to see how many brake lines go to the caliper. One line-it's not linked & two lines-it's linked. Haven’t looked at an '06 but it sounds like a unified system has the front brakes linked to the rear brake pedal but the rear brakes aren't linked to the front brake lever. Now this is not to be confused with the '2000 & back Goldwings & Guzzis with integrated brakes where pressing the rear brake also puts one of the two front calipers. Sounds kinda expensive doesn't it & it's all cause we don't know how to stop quickly & we keep running into stuff. Now get off your butt & go out and practice emergency braking! While you are at it, practice some curves too-anybody can go fast straight & that doesn't impress me. FYI braking distances for the Experienced Rider Course are: 13' for 15mph, 23' for 20mph, and 34' for 25mph. You should easily be able to beat these standards on dry pavement, as these distances are good for wet pavement also. If you hear your ABS coming on, then you aren't doing it correctly. O K, somebody start a new thread & let us know how quick U can stop...Later,,, De

 

[Cal24Master]

Here is how it works according to the service manual:

Each front caliper has 6 pistons, not 4.

The front brake activates all 6 pistons on the right front caliper and 4 of the 6 pistons on the left front caliper. It doesn't activate any of the rear brake.

The rear brake pedal activates 100% of the rear brake, and remaining 2 pistons of the left front caliper.

There is what is described as a "proportioning valve" between the front and rear brake.

The bottom line is the system works fantanstic. You can stand on the rear brake without locking it up, or even engaging the ABS, even on wet pavement. The rear brake actually stops the bike fairly quickly, and the front brake is as strong or stronger than it was on my 03.

I say quit worrying about how it works, and enjoy it.