2019 R 1250 RT Question about front/rear linked brakes

[vskinner]

Hello everyone,

I have a question about brakes on a 2019 R 1250 RT with the Pro option.

Is it correct procedure to only use the front brake when stopping?

The owners manual does talk about the front and rear brakes being linked, but it seems vague and it's only mentioned in the context of emergency braking:


From users guide under the Dynamic Brake Control section:
In the event of partial braking
with high brake pressure gradients,
Dynamic Brake Control
will increase the integral brake
pressure on the rear wheel.
This shortens the braking distance,
enabling controlled braking.


From users guide in the Riding/Brakes section:
To achieve the shortest possible
braking distance, the front brake
must be applied quickly and with
increasing force.


I cant find any text explaining the correct procedure during normal slow braking. Is it correct to only use the front brake??

Thanks Victor

 

[WWeldin]

The front brake lever activates BOTH brakes, whereas the rear brake pedal applies the rear brake only. As I see it, the Dynamic mode will be a lot more involved with braking. The more downhill you are and hard braking is required, sensors detect the angle and forward momentum and will essentially increase the amount rear brake pressure (when front brake lever is used.) Possibly, it may not matter on any foot brake lever input you have chosen. The computer tries to calculate everything (speed, gradient, amount of brake pressure input, wheel spin, and lean angle) to maximize the stopping distance.

Suffice it to say, unless you are using it for a track day, just ride it. Try not to over think how braking is affected by the riding modes. IF you are like me, you will just brake the way you have always trained yourself to do. For me, even knowing that the front brake lever will work both brakes, i still apply the foot brake. I am very impressed with the braking ability on my 1250 RT.

Normal braking will require just that - normal action.

Cheers,
William

 

[pauls1150]

"Only" the front brake? NO.

It depends on conditions and what you need to do at the time.

Yes the front lever activates the rear brake too, but any time I've read about braking distances (no I can't give a link or a quote), the best stopping distance always resulted from using both brakes.

And - if you ever need to panic-stop, you will do so using whatever method your brain and body have become accustomed to ... another reason to not limit yourself to just the front.

There's also "trail braking", where you use the rear only, lightly, to stabilize the bike in a curve.
If you ever roll backwards, the rear brake will be your main stopper.

 

[vskinner]

The front brake lever activates BOTH brakes, whereas the rear brake pedal applies the rear brake only. As I see it, the Dynamic mode will be a lot more involved with braking. The more downhill you are and hard braking is required, sensors detect the angle and forward momentum and will essentially increase the amount rear brake pressure (when front brake lever is used.) Possibly, it may not matter on any foot brake lever input you have chosen. The computer tries to calculate everything (speed, gradient, amount of brake pressure input, wheel spin, and lean angle) to maximize the stopping distance.

Suffice it to say, unless you are using it for a track day, just ride it. Try not to over think how braking is affected by the riding modes. IF you are like me, you will just brake the way you have always trained yourself to do. For me, even knowing that the front brake lever will work both brakes, i still apply the foot brake. I am very impressed with the braking ability on my 1250 RT.

Normal braking will require just that - normal action.

Cheers,
William

Thanks for your comments William. I think you identified my problem, I tend to over think things! I always used both brakes on my previous bike which did not have a linked brake system. When I got the RT, with linked brakes, I quit using rear brake thinking there was no need to that now, the bike will take care of that automatically. Thanks! Victor

 

[vskinner]

"Only" the front brake? NO.

It depends on conditions and what you need to do at the time.

Yes the front lever activates the rear brake too, but any time I've read about braking distances (no I can't give a link or a quote), the best stopping distance always resulted from using both brakes.

And - if you ever need to panic-stop, you will do so using whatever method your brain and body have become accustomed to ... another reason to not limit yourself to just the front.

There's also "trail braking", where you use the rear only, lightly, to stabilize the bike in a curve.
If you ever roll backwards, the rear brake will be your main stopper.

Thanks for you comments Paul, yes I think only using front brake, even on a bike with linked brakes, may be a bad habit to develop. Vic.

 

[kevinsclo]

Now here is my question...

Since the front lever activates both the front and rear brakes, I would assume that the hydraulics and sensors will optimize the pressure between the front and rear. Thus optimizing the load-balance of the braking power. Now if you use/activate both the front lever and rear-brake pedal, wouldn't you be upsetting and risking the brake pressure balance?

Ever since switching to riding a RT, I have learned to use the front lever for 95% of the time and only apply the rear pedal for tight corners or loose surface.

 

[pauls1150]

I don't "know for sure" but I have to think that the factory "optimizing" and "balance" would apply to "normal conditions". What are those?? It used to be touted that 70% of your stopping power is up front; I don't know if that's true today. Is the system set up to send 70% of your right hand's squeeze to the front? Dunno.

If I Really Need To STOP RIGHT NOW, I'll depend on my own skills first.

 

[3putt]

What rear brake?

 

[dlong]

"Only" the front brake? NO.

It depends on conditions and what you need to do at the time.

Yes the front lever activates the rear brake too, but any time I've read about braking distances (no I can't give a link or a quote), the best stopping distance always resulted from using both brakes.

And - if you ever need to panic-stop, you will do so using whatever method your brain and body have become accustomed to ... another reason to not limit yourself to just the front.

There's also "trail braking", where you use the rear only, lightly, to stabilize the bike in a curve.
If you ever roll backwards, the rear brake will be your main stopper.

A different take on trail braking. In its most common motorcycle usage, trail braking involves primarily the front brake, with perhaps light pressure on the rear (or none at all).

https://www.youtube.com/watch?v=gPE67XqGsV4

 

[pauls1150]

Thanks for posting that - it's a very good explanation.

EDIT:
But now I have a question: Wouldn't using the rear brake have almost the same effect - to a lesser extent - than the front brake? Inertia still transfers the weight forward, with less compression of the forks, so the change of rake is less; it also frees the rider (and I'm assuming from his post, and also his number of posts, that the O.P. is a new guy) from being too focused on coordination of his throttle plus front brake with one hand.
Is there a different term for "rear only" level adjustment, and I just used the wrong word?

Not trying to diverge too far from the OP's original question...!

 

[wbrownell9]

I don't "know for sure" but I have to think that the factory "optimizing" and "balance" would apply to "normal conditions". What are those?? It used to be touted that 70% of your stopping power is up front; I don't know if that's true today. Is the system set up to send 70% of your right hand's squeeze to the front? Dunno.

If I Really Need To STOP RIGHT NOW, I'll depend on my own skills first.

When a bike does a stoppie, 100% of the braking power in front. So 70% is, IMO, a minimum value.

I agree that when (not if) the time comes that you have to stop RIGHT NOW, you'll use whatever braking method you've practiced - the one in your muscle memory. There 's a thing called risk homeostasis: If the perceived level of risk in one part of a person's life changes, they will compensate by either reducing or increasing the amount & severity of risks they take - all in order to maintain an equilibrium of perceived risk. If I take more risks because I expect ABS, linked brakes, traction control, TPMS, whatever, to save me I've kind of defeated their purpose, which is to make riding safer than it would be without them. I ride as if they're not there, and if they kick in, I'm (1) grateful that the bike saved me from myself, and (2) alerted that I need to do a better job of reading conditions.

 

[ncpbmw1953]

Wouldn't using the rear brake have almost the same effect - to a lesser extent - than the front brake?!

Yep, and so does engine braking. As a proponent of The Pace I get stabilization of the suspension from just engine braking so no need to trail brake. And this is why at 41K miles the original front pads still have half their service life left . Comes from driving a hybrid auto I'm sure

 

[3putt]

Engine braking on the RT is one of the reasons I don't own a K1600.

 

[pauls1150]

So after some research (reading and You-Tube vids), I did a little experimentation today...

Of course either the front or rear brake - and/or engine braking - causes a weight transfer forward. The difference is how much and how quickly; note also that "how much" directly affects the rake and trail.

Rear or engine braking is smooth and gradual, and easily controllable under most circumstances (dry road, good tires, situational awareness, etc.).

Front braking causes a bit more dive, which can actually be useful if you need to tighten up the turn. More downforce on the tire will also increase traction.

Its downside is that, if there is sand, oil, or tarsnakes on the road (all pretty common where I like to, um, exercise), then a front "slip" of the wheel may be more difficult to recover from than a rear slip. The increased traction can help, but as I posted earlier: It depends on conditions and what you need to do at the time.