The evils of linked brakes

[RBEmerson]

Fred W wrote:

...As far as the linked braking, as has been established, the linking is unidirectional, front brake force added only when using the rear pedal, not vice versa. But there are also two valves that control the hydraulic linking. There is one valve that restricts the linking to the front until a certain pressure threshold has been exceeded. This allows one to trail brake with just the rear brake if you want to, or to manually apply front and rear brakes as you see fit. It is really only when you stomp on the rear pedal that the threshold is exceeded and brake pressure goes to the front.

There is a second metering valve that adjusts the amount of pressure from the rear master cylinder that will go to the front after that threshold has been exceeded, and there are three ABS circuits (front, rear, and linked) so that the linked front brake will not cause a wheel lock-up.

This whole discussion reminds me of the fairy tale, the Princess and the Pea. Of course YMMV

As with suspensions, I can also quickly get over my head with braking systems. That said, the notion that I must keep the point where the proportioning activates while busy dealing with why I went the rear brake to do the bulk of the work... which can lead to task saturation. That's not a good thing. ABS remains available, avoiding tire locking. That's a good thing. (It's been demonstrated that modulating brakes gives a longer distance traveled versus relying fully on ABS.)

I beg to differ on princess' and peas being applicable here. The analogy that I think applies is "when somebody makes something foolproof, somebody makes better fools". Or maybe it's worth examining the things that go wrong with self-steering cars. Maybe it's demanding a buggy whip socket on the dashboard (any want to take a crack at where that term comes from?) of a Ferrari, I prefer unlinked brakes or at least a safe way to unlink them. (Side note, there's an ongoing thread else where about how to disable ABS on at least one, and I'm sure more, bike. I view that as being on a par with relying on a throttle lock or the old, no return spring, HD throttle. AKA suicide throttle [/lock].)

P.S.: Post moved to avoid being struck by mods' lightning for being OT in a thread.

 

[Redfish Hunter]

WTF?

 

[Mr_Canoehead]

I can see this going to NEPRT in 3,2,1......

 

[SLK50]

Quote: WTF?

Relax. Youll get used to Rick after awhile. Maybe.

 

[FredRider]

Sorry, my old Commodore 64 is too slow to GAF about linked, ABS, unidirectional, etc brakes. I don't care how they work. All I know is when I grab a handful of front and a toe-full of rear, the bike slows down.

 

[FredRider]

Quote: WTF?
Relax. Youll get used to Rick after awhile. Maybe.

I've seen, and ignored his ******** for years on Sport-Touring.Net.

 

[wetwolf]

Is it friday already?

 

[lnewlf]

huh

 

[art miller]

RBEmerson's intellectual grammar is too copious for my diminutive comprehension therefore it is compulsive he elucidate and be more explicit as I cannot comprehend his momentous signification.

 

[RBEmerson]

Say what?

 

[RBEmerson]

The point I'm trying make is simply that if I step on the pedal I don't want (a part of) the front brakes, too. And the other way around; if I pull the lever, I don't want the rear brakes, too. Obviously I'm talking about the ideal bike. the FJR has linked brakes and I think that's less than ideal. But just maybe there's something I should know about FJR brake linking. Why not ask and learn?

 

[RossKean]

As far as I am concerned, there is NO downside to having the front brake applied (mildly - one piston pair out of four) with the firm application of the rear. The front won't lock up and may just be enough to save your butt when the rear loses effectiveness due to weight transfer to the front wheel. 75% or more of braking effectiveness comes from the front brake in a well executed panic stop. I have to say that there is nothing noticeable with the partial engagement of the front while just applying the rear brake. I would be surprised if anyone said otherwise.

Maybe its sort of like ABS or traction control. While theoretically you may be able to stop faster without ABS (or accelerate quicker on slippery surface without traction control) this is not so for the average rider under average conditions when not specifically prepared to take full advantage of a system that is not dumbed down in any fashion. When I grab a handful (or footfull) of brake encountering unexpected wildlife on a sand strewn piece of asphalt, I am grateful for the ABS and grateful for the linked brake if (in a moment of poor judgement) I use too high a proportion of rear vs front.

As for some of the Honda systems where the rear brake is also inked to the hand lever, I don't see much advantage in that.

 

[RBEmerson]

Back to front... I like ABS. ABS stops are demonstrably shorter than brake modulation. Not having really needed traction control (does this make me a wuss?), I have no opinion, save that what I've read leads me to think I like traction control, too.

Working from my (limited, two weeks) time in the Alps, where 14% grades show up, grabbing front brakes, during a descent, is not wise. Grabbing a bunch of rear brake first, and adding some front brakes later, has much to recommend itself.

Furkapass - 11% max (the fun starts around 13:30 and is in full play around 15:30)


Why worry about that in the US? I can think of one place to play near here - similar hairpins (only fewer) and similar grades. I'll take the same braking strategy, please.

 

[Heen]

As we get more mature in life, whether we like to admit it or not, our reaction time and skills diminish. I like the technology that helps.

RBEmerson, I would worry about it here in the US. I believe there are roads out west that can compare to the videos above. (may not be as scenic). Guys in the PNW, would the Rattle Snake Grade compare?

 

[lnewlf]

again-keeping in mind that the front brake only applies when pressure from the rear pedal overcomes the proportioning valve in the system,it required a fairly hard stomp.....the rear brake is never applied when the front brake lever is squeezed...

 

[RBEmerson]

As we get more mature in life, whether we like to admit it or not, our reaction time and skills diminish. I like the technology that helps.
RBEmerson, I would worry about it here in the US. I believe there are roads out west that can compare to the videos above. (may not be as scenic). Guys in the PNW, would the Rattle Snake Grade compare?

The good news is there is some research that indicates that "practice, practice, practice" or "use it or lose it" has a very positive influence on reaction times, and on skill retention. Or least I'm quite happy to accept the research results.

Not having been "out west" and only visited parts of the PNW, I can't comment on them. Yet. I'll know more after a trip west over the winter. (On our VW Westy's four wheels, but it's better than a poke in the eye)

At this point I think some poor dead horse has been beaten to hamburger. The FJR has what the FJR has and I'll learn to use the bike to the best I can.

 

[RossKean]

As we get more mature in life, whether we like to admit it or not, our reaction time and skills diminish. I like the technology that helps.

RBEmerson, I would worry about it here in the US. I believe there are roads out west that can compare to the videos above. (may not be as scenic). Guys in the PNW, would the Rattle Snake Grade compare?

The good news is there is some research that indicates that "practice, practice, practice" or "use it or lose it" has a very positive influence on reaction times, and on skill retention. Or least I'm quite happy to accept the research results.
Not having been "out west" and only visited parts of the PNW, I can't comment on them. Yet. I'll know more after a trip west over the winter. (On our VW Westy's four wheels, but it's better than a poke in the eye)

At this point I think some poor dead horse has been beaten to hamburger. The FJR has what the FJR has and I'll learn to use the bike to the best I can.

Yes, this horse is about finished! I don't think you are going to have to "adapt" to the FJR's systems in any way (brakes or suspension). Pretty seamless and very well behaved. The brakes are at least as good as any I have experienced on any large (heavy) bike.

 

[RBEmerson]

I have a response to that, but the flies around the poor horse leave me thinking I'll go find a nice veggie smoothy instead. Riding my FJR to get to the smoothy stand, of course.

Oh, another way to sum this thread up: "one man's Mede is another man's Persian". For anyone who doesn't like that, because they can't find the jokes in that... in yo' face, mo' fo'! oloo

 

[Redfish Hunter]

I think I hear your BMW dealer calling.