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Discussion Starter #1 (Edited)
I ride two different bikes with plenty of engine-braking power each (SV650 and Vstrom 1000) so for the last few years I became lazy regarding the use of my actual brakes to set my entry speed before entering a curve; I would just roll off the throttle enough to slow down and dive into the turn. (I live at the foothills of the central Sierra Nevada so I spend lots of time in my "backyard", which is full of amazing twisty roads).

Anyway, lately, I have been trying to be more conscious of the way I set my cornering entry speed and I started using both my front and rear brakes —as in lightly— to reduce my speed before entering the curves. My entry speed has remained basically the same as it was when I was simply engine-braking but there is a very noticeable difference in the way the motorcycle handles entering the turn. The bike feels more stable, better planted on the pavement and this, in turn, makes turning and getting back on the throttle much easier. The end result is a smoother and more controlled turn.

I'm sure there is plenty of detailed, technical information of why this happens (suspension compression, etc.) out there, but I won't discuss that here. Let's just say I get a very satisfying feeling by experimenting and discovering those little motorcycle dynamic quirks on my own.

Food for thought.

- Ofir


http://www.ofirmx.com/blog/2015-07-01/braking-vs-engine-braking-before-entering-a-corner/53
 

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It has to do with suspension mostly. When you brake - it causes the suspension to react. Same when you accelerate - which is why you should brake before a corner and then accelerate smoothly through.

And yes - there is a lot of physics involved and would have been fun for me about 20 years ago. Now, it'd just be a headache figuring out all the forces...
 

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Maybe it all depends on whether you are out for a pleasurable ride of trying to conquer the road. I can ride Angeles Crest at it's posted speeds and not use the brakes. My buddies ride like stink and use everything at their disposal.
Roads like those in Sequoia Nat Park will have you using the brakes even of you down shift for engine help.Thankfully the Sierra's are full of roads like that to entertain us!
 

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Using both is prudent..using the front brake loads the front tire - slightly increasing the size of the contact patch and also forces the front tire onto the pavement, but it also tends to unload the rear tire. Watch the real pro road racers - they will use that unloading to assist sliding the rear of the bike around to assist in tightening up the corner..
 

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Being in the right gear to me is much more important, but I am an engine braking guy myself with a bit of speed scrub off from the brakes before entering the curve "if needed".
 

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I thought "The Pace" was a good set of principles for spirited Street riding:

The Pace | Nick Ienatsch | Motorcyclist magazine

The author has revisited it with "The Pace II":

The Pace 2.0- Motorcycle Safety and Riding Skills Explained: The street is not a racetrack: How to ride swiftly and safely on the road.

..Tom
Great advice and thanks for the link V-Tom... and clearly the author and I both culminate with this, "Let me close 2.0 with this: Most of us don’t approach our riding improvement seriously enough. Get relentlessly focused on your riding, don’t put up with riding errors...". In another Proficiency thread I talked about my 'Demerit System' and I think a lot of other riders could benefit from critical self-assessment.
 

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Here's what he says:

"
Let me close 2.0 with this: Most of us don’t approach our riding improvement seriously enough. Get relentlessly focused on your riding, don’t put up with riding errors, don’t think “good enough” is: When you add speed to mistakes, you don’t just hit the ball into the net. Our riding mistakes not only hurt bodies and wallets, but our sport, as well. Consider giving this article to your friends, or adopting it for your club. More important: Carefully evaluate the riding advice out there and seriously study how you ride your pace. It may help save our sport.


Riding well is the most wonderful feeling in the world, the reason we’re all hooked, and that’s what The Pace celebrates. You’re riding quick and controlled. Your friends file through a tight, left-right-left with the fluidity of a rushing stream. Your mirror is filled with friends riding your pace, using their eyes, brakes, throttle and body to ride with you. You arrive together. You and our sport are healthy tomorrow. The best."


..Tom
 

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brake which wheel? when? how?

By the time I'm fully turning, I want the bike at the speed which I intend to maintain through the rest of the turn. This is because I want the fore/aft downward force distribution to match the fore/aft mass distribution, which then yields the same ratio of required turning traction to normal force on each contact patch. (Given the same rubber compound and pavement condition at each patch, this match then provides the same traction margin for each wheel.) Anything which reduces downward force on one patch or the other, such as deceleration or acceleration, is going to reduce traction margin over that available at steady speed.

Now, getting to this thread's topic: It really does not matter how you reduce speed while approaching a turn as long as speed is steady through the turn and the suspension has had a chance to stabilize before the bike is fully leaned.

I find that the rear brake is a little better than the front during the entry and initial partial lean, because it seems to disturb the fore/aft weight distribution less. I also find that engine braking alone is frequently enough, probably because most turns can be safely taken near the speed limit and I've been trying to avoid fuzz interactions. I doubt there is any real difference between engine braking and getting the same deceleration from the rear brake.

If the topic is the best brake(s) to use well into a turn (when fully leaned), or so late in the approach that the suspension will not timely settle to that equal traction margin condition, then I would say: (1) You're doing it wrong; and (2) Do whatever produces least motion of the suspension. (Looking at the physics, I see no reason to believe that, for the same deceleration, braking one wheel will produce less torque upon the bike/rider system than braking the other. They both act with the same moment arm on the same center of mass.)

More important for any pre-turn braking than which mechanism to use is how it is done. If enough late braking is needed for it to matter at all, then a non-jerky release (and perhaps application) will better maintain the optimal fore/aft weight distribution, giving the most traction margin.
 

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...(Looking at the physics, I see no reason to believe that, for the same deceleration, braking one wheel will produce less torque upon the bike/rider system than braking the other. They both act with the same moment arm on the same center of mass.)
...
The front forks being raked back means that some of the braking force in the front wheel compresses the forks more than the same amount of deceleration caused by braking in the rear. BMW spent a lot of effort inventing their "Telelever" suspension to conteract the effect.

..Tom
 

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suspension upset versus front/rear braking

[In response to my writing, "Looking at the physics, I see no reason to believe that, for the same deceleration, braking one wheel will produce less torque upon the bike/rider system than braking the other. They both act with the same moment arm on the same center of mass.", Tom wrote:]
The front forks being raked back means that some of the braking force in the front wheel compresses the forks more than the same amount of deceleration caused by braking in the rear. BMW spent a lot of effort inventing their "Telelever" suspension to conteract the effect.
Ahh, yes. The backward force Ffb on the front tire can be decomposed into 0.45 * Ffb compressing the fork and 0.9 * Ffb exerting a bending force on it. And, similarly, a backward force Frb on the rear tire can be decomposed (using rough measurements) into 0.29 * Frb compressing the rear springs and 0.96 * Frb tending to elongate the swing arm. These compressions are in addition to the front compression and rear decompression that either braking causes by torquing the whole bike around its center of mass within the frame.

(At this point, I retract my "I see no reason ..." assertion. Thanks for the insight. It certainly explains (to me) why the rear brake seems to less disturb the suspension.)

I'll have to do a little more math to see how front and rear braking should be distributed to minimize fore/aft rocking effects. I suspect rear brake alone on approach to a turn is a good choice because it will more equalize the front and rear compressions than anything else.

None of this should be taken to suggest that hard braking when well leaned in a turn is sane. Regardless of these suspension compression effects, weight is transferred to the front wheel during any kind of braking, and that necessarily reduces traction margin on the rear wheel, (the one which sees the most centrifugal force). If you are truly approaching the traction limit in a turn, you'd best decrease the curvature before using an appreciable fraction of the available traction for braking.
 

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I'm lucky enough to have a couple of professional road racers as friends...I'll ask them for their thoughts on this...
 

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Don Emde responded to my question...he said that he really didn't know that much about Vstroms, didn't know if they had ABS or not, although he did know that they are dual purpose bikes..he reckoned that he couldn't tell a bunch of seasoned Vstrom riders much..A friend of Erik Buells offered the opinion that it all depended on speed...higher speeds required brakes, lower speeds could be handled by engine braking-so, pretty much common sense...
 

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I would agree with the ride and learn. Assuming a rider has taken a riding safety course. And has some reasonable close curvy roads. Ride them several times using any combination of throttle control and braking to see what works best for them. Pace isn't universal. Which seems like what the article is pushing. If we ride to enjoy the ride then pace will come naturally, right?
 

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...here are some more replies to the question ..posted on my facebook page..

Ask anyone who races, engine braking is a great thing. But it needs to be tuned to the bike, racetrack or comer to be as effective as possible. Sometimes you don't need the full anchor thrown out, but some engine braking will allow the bike to keep the suspension loaded and in the stroke for better cornering where you might not be able to trail brake as deep. Too much freewheeling will allow the bike to run wide and be harder to control the line. It won't finish the corner so a rider can get on the gas just before apex.

Does any of this apply to a Strom on the street? Maybe, but if you're threshold braking on the street you might wanna consider switching to track days. Too easy to go wrong and have serious consequences. It should also be noted that the problem with engine braking is it's not linear in force, where when you're working the brake lever you can apply linear force or in this case brake pressure.
 

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I would agree with the ride and learn. Assuming a rider has taken a riding safety course. And has some reasonable close curvy roads. Ride them several times using any combination of throttle control and braking to see what works best for them. Pace isn't universal. Which seems like what the article is pushing. If we ride to enjoy the ride then pace will come naturally, right?
I think "The Pace" is more a set of principals than anything else and, while I think these principals are very important when riding with other riders, I think they also apply very well to most spirited street riding.

..Tom
 

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I'm not close to being a great rider, but for normal street riding (an acceptable average pace for a given road), engine braking probably would be sufficient. I find that on the roads I know well, I mostly use the engine and gearbox for the next curve and try to flow through the curve with smooth throttle. It seems if you are in the right gear and RPM entering the curve, throttling smooth and looking through is most important, regardless of how you slowed. I noticed this week while on a ride to Durango and back, on some great CO roads, that in multiple back to back curves, it's as if you just surf through with the the throttle and your eyes once you set the correct speed. Fun!

I think race track comparisons are not always helpful, because in that environment, you are riding at the limits of yourself, the machine and the track. People ride hard on the road sometimes, but we all know the limits there are much less and less tolerant.
 

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... probably because most turns can be safely taken near the speed limit and I've been trying to avoid fuzz interactions.
...
One thing about speed warnings: In (southern) Ontario, Canada the speed warning signs for curves are generally set way too low. They seem to be set for the lowest common denominator, that is a fully loaded semi or double decker bus with a full load. Here you can often go a few times the warning signs knowing the bike will have no issue with the curve. Other areas this isn't so.. I found in many places in the US the warning speeds were something to pay attention to. You might go a bit faster than the warning but not a lot faster.

..Tom
 

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Other areas this isn't so.. I found in many places in the US the warning speeds were something to pay attention to. You might go a bit faster than the warning but not a lot faster.

..Tom
It seems to be a mixed bag in the States. Even within the same state or town. I generally find that the slower the suggested speed is, the closer it is to actual safe speed. The usual example being 10 MPH in mountain switchbacks really means 10 MPH. As the suggested speed goes up to, say, 30 MPH, sometimes 45-50 MPH is okay. But not always. I go by the sight lines too. Sometimes, even on a new road, you can tell a given curve is marked way too conservatively.
 

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And then, just to make things really interesting, are declining-radius turns. They're always a fun surprise!
 
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