Linked braking systems

[Scotwing]

Having owned a GL1500 wing with dual linked brakes, I was wondering if the ST1300 has the same kind of linled braking system? With the wing I mainly used the brake pedal for most of my braking. This activated the rear brake and also one of the front brakes. The brake lever was only used to add that extra braking when stopping quickly. Does the ST13 have the same type of system ie: is the break pedal sufficient for the majority of stopping power, or should I be using the front brake more. A few of my biking friends suggest that I should only use the front and ignore the rear? Ok guys what,s the correct procedure?

Joe

[SteveST1300]

I use the front about 85 to 90% as it pulls in the rear as well. I use the rear if I need to scrub a bit of speed off as I enter a turn. I was taught not to use the rear much maybe 15-25% rear brake. It works for me.:03biker:

[tommyboy]

Scotwing, no, the ST's braking setup is different. I migrated from a GL1500 to the ST myself.
The ST's brakes are all linked together. each caliper has 3 pistons. when you pull in the brake lever it actuates the two outer pistons in the front calipers and the center piston in the rear brake caliper. When you use the rear brake pedal it actuates the two outer pistons in the back caliper and the center pistons in each front caliper. It does not take much to get used to it, but you cannot rely on the braking power of the pedal alone in most situations.

[ST13Fred]

To add to what has been said, a delay valve briefly interupts braking to the front to get the bike to settle onto the suspension limiting excessive nose dive. It has Anti-Lock brake (ABS), also. In short, this stead has a killer braking system.

:04biker: :)

[MidLife]

Scotwing, no, the ST's braking setup is different. I migrated from a GL1500 to the ST myself.
The ST's brakes are all linked together. each caliper has 3 pistons. when you pull in the brake lever it actuates the two outer pistons in the front calipers and the center piston in the rear brake caliper. When you use the rear brake pedal it actuates the two outer pistons in the back caliper and the center pistons in each front caliper. It does not take much to get used to it, but you cannot rely on the braking power of the pedal alone in most situations.

Looking at the Service Manual, I get a slightly different picture:

-- Pull the lever and the two outer pistons in the two front brakes will engage.
-- Then the Secondary Master will be activated and engages the two outer pistons in the rear via the Proportional Control Valve.

So by pulling the lever, you end up with two pistons activated on each brakes.

-- Press the pedal and the middle rear piston engages.
-- Then the two middle front pistons engage via the Delay Valve
-- Then the Secondary Master should activate and engage the two outer pistons in the rear.

So by pressing the pedal you should end up with the three rear pistons and the two middle front pistons engaged.

At least that's what I understand from the Manual!

[HankSTer]

I find alot of discussion about the linked braking systems but believe it's really irrelevant... here's why:

at least 70% of your stopping power is in the front, so you definately want to be in the habit of using it. And when an emergency braking situation occurs (which we can't predict and usually have only seconds or fractions of seconds to respond to), you'll want your maximum braking available, which is "BotH" brakes fully, without locking them up.

so other then 'unusual' situations, like low speed in a parking lot, or scrubbing a bit of speed in the twists, most times you'll want to be in the habit of using both brakes. It needs to be instinctive. I think we should force ourselves to do it, to make it a habit, just in case it's ever needed.

It's not like we can find ourselves in the middle of an emergency and then go "oh, I think I should use both brakes now"... too late.

The MSF, along with teaching proper application of the front brake, recommends using both brakes all the time, just for the reason mentioned above. I subscribe to it, and never give a thought to linked brakes... excpet when it comes to bleeding them :eek:

Regards,

[Bob Hughes]

Looking at the Service Manual, I get a slightly different picture:

-- Pull the lever and the two outer pistons in the two front brakes will engage.
-- Then the Secondary Master will be activated and engages the two outer pistons in the rear via the Proportional Control Valve.

So by pulling the lever, you end up with two pistons activated on each brakes.

-- Press the pedal and the middle rear piston engages.
-- Then the two middle front pistons engage via the Delay Valve
-- Then the Secondary Master should activate and engage the two outer pistons in the rear.

So by pressing the pedal you should end up with the three rear pistons and the two middle front pistons engaged.

At least that's what I understand from the Manual!

Very nicely written, good posting.

[Carl_T]

Can't remember which but a magazine set out to test this on a 600 to see what was up in the real world.

Best measured stopping distance from 60 was indeed with both brakes being used. The measured distance was 146 feet

Next best stopping distance was with the front brake only
measured distance was 151 feet

That's all of 5 feet difference folks.

The worst stopping distance was measured with the rear brake alone
measured distance was 289 feet

That's all of 143 feet difference folks and that's nearly double what the front alone was.

Now the heavier, larger ST makes a bit better use of the rear than my SV, but I did get good stopping power out of using the front lever alone, the brakes being linked. That's not what I did with it in the end though.

[Carl_T]

Right or wrong, I came to normally use the brakes on the ST similar to how I use a non linked system. They worked very well that way and it kept me current for when I got on a non-linked bike.


For me that is:
Rear brake application is as follows (for most general braking) "first to go on and last to go off."

That is unless it's a really hard emergency stop where the rear then tapers down to nearer nothing as the weight gets severely transfered up front.

For me, I also take into account the percentage of stopping power I think the rear brake is capable of, for the given type and weight bike I'm riding (of course you learn to judge this exactly through feel feedback). That's as in, I press the rear pedal harder on a cruiser or even an ST, than on my 650 SV.

On the SV I press the rear pedal what I think is about 10% of the stopping power and front lever pressure/stopping force I want. The other 90% comes from the front tire, brake, and lever on the SV during a normal stop. The ST as I remember, was good for some bit more rear brake force than that due to size/wheelbase/weight

In normal braking though "the rear on first" helps settle the chassis as it starts the slowing process. The front comes on moments later and gets squeezed (cadence about what it takes to say "one thousand"). The front is tapered off some bit before stopping and the rear is done moments later. Less brake dive, less bounce back, and for my old brain most importantly, no need to relearn if you jump on a non-linked bike.

There are techniques to use the rear on first and off last entering turns, but it must be done in the right place in the turn and done for a specific effect. It's not a track style trail brake towards the apex thing. The technique can settle the chassis better, make the bike initially steer in better as well. However it places a rider at greater risk and requires that the rider to be consistently outstanding at turn entry speed setting, so it's probably better not explained.

When speaking of road riding between newer, average, and the general well experienced rider, it's likely best to leave the above be. It serves best to point out how much safer it is to finish braking soon enough so the chassis has already rebounded and settled before turn in (even though with this technique it will compress again at turn in), and how much safer it is to set turn in speed lower than what is possible. Also how much smoother and safer it is to set turn in speed low enough so it is easy to roll on the throttle gently through the whole turn, getting more aggressive with roll on, only as your exit line straightens out and you are lifting the bike (avoiding spinning up the rear tire or breaking it loose). Slow in fast out.

The safety of the above style comes from the fact that single rider turn accidents (on good pavement and non obstructed turns), are often due to mostly pushing entry speeds too high, and bad lines.

Related to pushing entry speeds too high, It's probably useful to point out many turn crashes are reported to happen from panicking mid turn and chopping the gas fast, or snapping on the brakes also. Overload the front quick enough and it can disappear.

"Roll on through the whole turn", it's also good to point out, that's better as a goal, NOT a RULE.
Flexibility to fit the actual situation at hand is most important.

Better to enter slower, pick a good line that allows for an exit radius that progressively opens up, where you can make up for the slower entry with a clean exit due to the bigger and bigger exit radius on your chosen line (from late apexing). Of course this type line (outside late turn in, inside, outside) assumes good pavement without traps.

How'd I get writing about turns and lines here? Oh yes thinking about issues related to braking into them. In riding everything you do is interrelated, one thing allows another to be possible, or one thing builds on another. Such as an incorrectly shaped line can cancel the possibility of a gentle roll on through the turn (one example in many). The line ridden and throttle use are interrelated.

To give my own personal answer to the original question, even though linked brakes allow for varying techniques due to the link, they also work very well using what would be good technique on an unlinked system. That being the case I found it (in general) personally useful to brake as though they were not linked. That allowed me to be able to jump on any unlinked bike at any time, and be right in the groove without practice or relearning.

I would not want to ever use just the rear brake pedal even on a Wing which you pointed out seemed to allow it, and that would be poor practice on the ST.

If I'm remembering the ST right, rear brake tapers on a tad before the front at around 15-20% stopping force, front tapers on just after rear application at around 80-85% STopping power. Then front tapers off just a bit before the rear, and front is fully off as the rear is finishing coming off. Also there is not a great deal of time between when one goes on and the other comes on. Same thing for coming off. You're not traveling a long ways with just the rear on alone. It's just a stability adding factor.

Necessary to say, in a full on emergency stop, right or wrong I taper off the rear brake first as the front really gets the bike's weight transferred heavy on the front tire, and it feels like the rear is getting very light.

So in a maximum force stop "rear goes on first and comes off first." It goes on just a split second before the front and comes off when the stop is progressing to full weight transfer. There is no point in leaving it on if the back is so light the rear tire has no traction.

[MidLife]

So in a maximum force stop "rear goes on first and comes off first." It goes on just a split second before the front and comes off when the stop is progressing to full weight transfer. There is no point in leaving it on if the back is so light the rear tire has no traction.

Carl_T,

As usual, you make a lot of sense.

But on the ST, when you let the rear off, you still leave two of the rear pistons engaged. Then all you can do is rely on the PCV magic to prevent the rear to lock up!

[Blrfl]

Rear brake application is as follows (for most general braking) "first to go on and last to go off." ... In normal braking though "the rear on first" helps settle the chassis as it starts the slowing process. The front comes on moments later and gets squeezed (cadence about what it takes to say "one thousand").

That's good advice. I learned early on to feel the forces as the weight transfers from the rear to the front. (No, Obi Wan Kenobi had nothing to do with it.) I go rear first and bite into the fronts when I feel the weight move "through" me. ("Use the brakes, Luke!")

It's a little like throwing a baseball: throw some weight from the rear and catch it with the fronts.

--Mark

[nm6r]

But on the ST, when you let the rear off, you still leave two of the rear pistons engaged. Then all you can do is rely on the PCV magic to prevent the rear to lock up!


Oh contrare, that's the beauty of ABS! Neither the front or rear will be locking up.

Ray
http://www.frontiernet.net/~st1300rider/smile04Bikerwheelie.gif

[MidLife]

Oh contrare, that's the beauty of ABS! Neither the front or rear will be locking up.

Ray
http://www.frontiernet.net/~st1300rider/smile04Bikerwheelie.gif

Hey Blue Ray!

You are making a good case for ABS here, but it looks like this thread is about LBS, not ABS.

What I was trying to say is that even if you let off the pedal while keeping the lever pulled, you are still left with the two outer rear pistons engaged. And you have no direct control on how much breaking force is then applied on the rear. Don't get me wrong, I have no complaint about it. The ST LBS works great for me. I am just wondering how it all works!

I wish I could understand how the PCV works. Because this is the valve that must be regulating the pressure applied from the SMC on the rear. Have no idea how it functions, but so far have not locked the rear yet (w/o ABS!), so the PCV must be doing what it is designed for.

[Carl_T]

I'm way out of any possible manner of expertise here with the following, but I'll put it out there.

I'm thinking perhaps the linked systems came into being mostly to compensate for a segment of riders who just did not, could not, or would not, learn to stop well with both brakes and too often used the rear brake only.

I was nervous buying the ST as it was my first linked system and not knowing enough about it from personal experience, I certainly had the same concerns as mid-life just mentioned. After thinking long and hard about that, I reasoned if I was going to break down and buy a bike with a linked system I'd spend the dollars for ABS as well to avoid any potential troubles with a linked system not modulating front to rear in a good way for conditions. I was concerned about turns in steep down hill gravel roads for one thing.

I didn't have the ST long enough to run into every possible scenario for the linked system so I still think there may be scenarios where I'd wish not to have it at all (I sure wish Honda had put a disable switch in there for a long gravel road ride) , but I will say I found it better using it in practice than I ever expected to. I had expected to find it very intrusive, and did not really.

I probably would still only want to have ABS with a linked system though, for those rare times that I still think have potential to arise, where the link is a detriment of sorts. ABS and the link seem to go well enough together if my ST was any indication (though I'd personally still rather have ABS and unlinked).

Since the ST will take a bit more rear braking than the average sportbike, it's probably a better candidate for a link than sportbikes. Myself I'd still avoid a light sportbike with a link if I could.