Safe Speed Forums

Just out of interest... what principle is that?

Mike.

Quoted for emphasis.

Slow down fellas, give me a chance to respond

The reason that I disagree on Honda's linked braking system is that I like to decide which brake I want to apply when. As I understand it from memory: the back brake, when applied, will also bring on one of the front brake pots and applying the front brake will activate one of the back brake pots. In certain circumstances you will not want the front wheel braking when the back is being applied, such as in slippery conditions where a slide from the back is much more controllable than the slide from the front.

Also I tend to use the back brake for a bit of extra steering if I have to tighten my line through a corner in circumstances such as when a suicidal rabbit runs out in front of me. On a fast, open, good visibility corner when you are leaned over, you do not want any front brake applied.

Also see previous post regarding deisel spill

Edited to add:
Another reason is that I get much more mileage out of my back pads as I do tend to use the back brake less than the front. If the brakes were linked then I would have to fork out for more pads more often and why should I do that just because Honda dictate that linked brakes are better than standard brakes.

I've no opinions on ABS on bikes as I have, as yet, not ridden a bike fitted with it.

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Prepare to be Judged

My VFR800 has linked-brakes and I’ve now clocked up about 75k miles, riding in all conditions and on all road types. I have never found any noticeable difference to riding a bike with conventional brakes.

I can use either or both brakes and the response is totally as convention would be. It leaves me to wonder why Honda ever decided to unnecessarily complicate the system. It is completely transparent.

The only time I suspect there is a noticeable effect is under heavy emergency braking, when using both brakes would be the preferred option anyway.

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It's tricky doing nothing - you never know when you're finished

Don't knock it 'til you've tried it, basically.

That's pretty good advice

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It's tricky doing nothing - you never know when you're finished

Unbelievable in the wet, pretty un-amazing in the dry. My triumph has independent ABS (ie separate systems from and rear). Once You have faith in it you can really use the front brake in the wet. I have only triggered it a dozen times but you have that extra factor so you can attack the brakes in the wet.

I have seen tests (notably in Bike) where racers outbrake bikes with ABS on conventional brakes. I asked bike if the ABS was actually activated but they did not comment.

Not like car ABS though; you can not brake and steer. If you use the back brake hard in a corner the ABS might 'work' but it will not stop a slide. Funnily enough I have never tried this on the front . Basically it stops brake induced skids but slides from trying to use more grip than you have are your own fault/problem

I have always focused solely on getting maximum effect from the front brake and ignored the back in emergency situations. The logic is if there is weight on the back so it has grip you can use the front harder. This changes slightly for heavily loaded/pillion situations.

Of course others technique might vary but if you want a 100 to 0 race.......

I would recommend practicing emergency stops on a bike repeatably. The front brake and tyre on a modern bike is an awesome bit of kit. As long as you do not snatch (ie wait for the weight transfer) you will struggle to lock a front wheel. Based on my experience I think you could be looking at stopping from 100 in around 150 - 170 feet. (ie well within a pair of hundred yard markers.

BTW repeated emergency stop practice on a GSX600 have lead to overheated discs but I can really stop quick now!

I can only comment on the linked/ABS brakes on the new 700 Deauville as that's what I have.

The back brake, when applied, will also use one of the six pistons in the front brake. The front brake does not apply the rear and remains independent.

As it only uses 15% of the power of the front brake when using the rear it doesn't exactly 'jam them on'. I find that braking hard with the rear you do feel the front apply but the feeling to my mind is that of pulling the bike down to the road more than anything else and it seems to settle it nicely.

I've used the rear to tighten a line mid corner and not felt that it was detrimental to have the linked system. But, it's a Deauville so I'm not going at supersonic speeds. (but I don't hang around)

I have consciously tried to lock the rear to see how the system behaves. From a decent speed I literaly stood on the rear brake pedal and the bike came to a stop pretty quickly with no undue dramas. Whether that's the linked system or the ABS I don't know, but I didn't feel the ABS taking over (perhaps I'll actually have to stand up on it next time).

With regard to balrog's point: My return journey from work takes me off a fast dual-carriageway up a slip road to turn left onto a B road. I can go up the slip road doing at least the NSL and am well past the 90yds give-way warning sign before I apply the brakes. Again, no dramas, just a strong, smooth stop well short of the line. Compared to some of the bikes (and cars) I've driven the brakes on the Deauville are excellent.

Mike.

Edited for some typos.

Believe me when I say that you'd know if you'd engaged the ABS! The 'buffet' through the lever/pedal is noticeable.

Obviously, a lot of truth in what you say. Some even swear never to use back brake unless they are moving at walking pace!

I would maintain that for normal (heavy) road braking, a bit of back will stop you quicker than front alone.

As you say - always good advice to practice these things before you really need to use them.

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It's tricky doing nothing - you never know when you're finished

Ahh, this raises an interesting issue that I've been pondering...

If a modern motorbike will lift its back wheel under braking force (a 'stoppie'), then at that point the entire weight of the bike is acting on the front wheel, and the back brakes can do no work.

So I don't understand how you can stop quicker by using the back brake.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

But you don't do a stoppie every time you brake hard, in fact it's very difficult to do it, even intentionally, on a big bike. As long as the back wheel is in contact with the road and rolling, then more stopping force could be exerted by retarding the back wheel as well.

Yeah, that's why I said 'normal (heavy) road braking' - ie not full-on, bottom clenching, emergency braking. Practising in car parks with cones will demonstrate reduced stopping distance using both brakes.

I've never had the pleasure of a 'stoppie', but I'm sure it involves a serious grab of the lever. One would normally feather the brake before that situation arose.

Edited to add: I think Robin has explained it better than I have!

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It's tricky doing nothing - you never know when you're finished

I think that's technically correct but there is a subtlety.

Ideally you need a bit of back to aid judgement of the amount of safe brake force available (‘safe’ meaning both wheels on the ground). Doing so will still ensure maximum brake utilisation whilst minimising the risk of a ‘stoppie’. Overdoing it will instead result with locking the rear so serving as an early warning of a stoppie.

Once a stoppie has been pulled, the higher the angle, the less you can decelerate (you have to ease off the lever) without topping over, you also have to further reduce braking force to eliminate or prevent further onset of it.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

But there's a hole in this argument. You're saying: "I would maintain that for normal (heavy) road braking, a bit of back will stop you quicker than front alone." BUT ALSO "ie not full-on, bottom clenching, emergency braking."

So you can brake harder using the back brake until you're braking really hard, then you can't? So why can't you just brake harder with the front brake in the first place?

I'm not trying to put you on the spot here, and I can genuinely see serious usefulness for the back brake in normal driving - but something doesn't quite add up.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I thought exactly the same thing after I posted!!

I'll think about it.....

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It's tricky doing nothing - you never know when you're finished

Yeah, but equally: as long as the back wheel is in contact with the ground you can still brake harder with the front brake. (Assuming that the end point is the back wheel lifting rather than the front wheel losing grip).

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

You've got to be pretty brutal on the front brake to get the rear wheel to lift and (I stand to be corrected here, but) it tends to only be after a lot of initial speed reduction.

If the rear wheel is only going to lift once the initial speed reduction has taken place then you are wasting the opportunity of having the rear wheel on the ground and assisting the braking effort to reduce the speed more rapidly before you get to the point the rear wheel lifts.

If you watch someone doing a 'stoppie' they come hurtling along, brake hard and then as they slow they lift the back wheel. I think it would be hard to stand a bike on its nose, at say, 70mph

(I hope that makes sense)

Hard, certainly, and foolish, I dare say.

But the fact remains that with the approximate capability to lift the back wheel under braking force, the approximate contribution from the back brake is zero.

My guess is that the ultimate resolution of the point is this:

- the back brake is a good stability aid under normal, even enthusiastic, braking.

- However as the emergency need to brake grows, so the back brake becomes increasingly redundant.

- But where grip is lower and there's not enough grip to lift the back wheel, then the back brake is a valuable contribtutor because it increases the size of the braking contact patch.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety