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The Art Of Safe Riding
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#1 (permalink) | ||
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Always wear a helmet!
Join Date: Dec 2009
Location: India
Posts: 15
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Few riders realize that the front brake is the most effective in a two wheeler. Just using the rear brake allows you to barely use some 30% of the total braking force possible. Using the front brake is like pushing the bike from its front against its direction of motion and this is far more effective that trying to pull it to a stop by hanging from behind it. Moreover, using the front brake throws a lot of weight on the front tyre and this allows it to grip the road better. Grade your braking so that some 70% of the braking effort comes from the front brake while the remaining 30% from the rear wheel. The rear brake is primarily to stabilize the bike and preventing a violent weight transfer onto the front wheel. Too much rear brake will lock up the rear wheel and the bike slides out of control. The only precautions while making full use of the front brake is to keep the bike upright and avoid its full application on wet or gravel roads. In slippery conditions, use the rear brake sparingly while making the most of the available engine braking. And while in a turn, try and straighten up the bike as much as possible before applying the brakes. Stop turning before you start braking.
Get used to the front fork dive on applying the front brakes. Be smooth but firm in the brake application (squeeze the lever as if it is the trigger of a gun, don't grab it). The harder you learn to apply the front brake and the sooner you can get it to its full power, the shorter will be your stopping distance. Tips about braking:
Photo: Stopping distances for the three different brake combinations ![]() ![]() ![]() Photo (below): Ideal configuration for panic braking ![]() REPRODUCING POST FROM HERE ON PAGE 6 FOR EASY REFERENCE There's a well known adage in aviation, particularly for fighter pilots, and it goes like this: When an emergency arises your performance drops to the lowest level of training. I have never come across a more realistic observation of deterioration of skills when under hostile fire. Practicing for emergencies is as good as the emergency simulation you do, actually a little worse than that. Which is why you need to practice so much that the needed actions become second nature, a 'reflex'. And practicing the 'right' technique is critical because the 'reflex', once embedded in muscle memory, will not allow you to think and correct it if its wrong. What Tenhut, csgup1, rossiter and quite a few others have put forth here is about not just the need to learn the skills but the criticality of learning the RIGHT technique. Becoming a proficient motorcyclist is a lifelong endeavor. You are either busy learning new skills or practicing old ones. Braking is a very 'critical' skill for a motorcyclist. The real art in going fast is to know when to go slow and how to go slow. And getting it right, practicing it right and executing it right is what will keep you alive. Its one major 'vital' in the Vital few and trivial many aspects of motorcycling. Learning braking in real life urban riding situations is about including road traction assessment into your braking action. Practice the gentle squeeze to firm squeeze technique any and every time you brake while riding. Feel the firming up of the front brake lever under you fingers. Scan the road ahead for adjustments to braking. Check those RVM's before, during and after braking. Feel the weight transfer drop the front and know that the rear has gone light by an equivalent amount. Practice each and every time you brake, so much so that you unthinkingly brake like that everytime. Aim for a point to stop and see how well you assessed the distance and braking effort needed. See that little piece of paper on the road, try to steer around it while you brake. Set up your line and entry speed to those turns to perfection. In a well set-up turn, whether on road or on track, you'll not need emergency mid-turn corrections. It is only when you set up a turn on assumptions rather than knowledge of the road/track ahead that you need mid-course corrections. Incessant learning is essentially what it is all about. Remember that a skilled rider will use his skilled brain to avoid needing those superior skills. Paradoxical but actually the only real way of enjoying your motorcycling and yet staying alive doing it. Lots of useful information has been shared about 'trail braking' here. I'll add a visual aspect to it and start with a diagram that I've taken from a book 'Sport Riding Techniques' by Nick Ienatsch. The orthodox riding technique states that we finish all our braking and gear shifting while the bike is upright, enter the turn on constant throttle and just past the apex, feed in the throttle progressively. But the preferred method now is using 'trail braking'. Trail Braking is a technique where the rider progressively reduces his braking force as he gets deeper into the turn and closer to the apex. This progressive and smooth reduction in braking is to use a progressively larger share of traction for turning, a need that hits its maximum at the apex, where the braking input is reduced to zero. Trail braking has two major benefits: 1. It allows for braking while turning, allowing the rider more control over his situation. and 2. The rider can carry speed deeper into the turn and by slowing progressively towards the apex, has more reserve traction to trade for the same needed for turning. Post-apex, progressively opening the throttle makes for gradual rearward weight transfer allowing the rear tyre time to gain traction and transfer power for acceleration. In practice, the overlap between trail braking and powering out is a smooth blend, always balancing the available traction to the traction needs. Trail braking is a difficult skill to master primarily because as you brake during the turn, you put additional loads on the contact patches which are already fighting a hard battle for traction by countering the outward tangential force. Adding braking loads to the equation takes you closer to the edge of the traction envelope and even a slight excess in loading can lead to a washout. As for the unassailable logic of favouring the front brakes, the related and at times disconcerting nose-dive and what happens when we do so was something I had posted earlier in another thread here quite sometime back. Reproducing the same below to maintain continuity as has been the case with the trail braking part above which is also taken from the same thread: I guess we need to get back to high-school physics to clear this thing about forward weight transfer under braking, its benefits and demerits in its entirety. Weight transfer is a physical reality that has to happen, whether there is a suspension system pre se or not. Refer to the fig in my previous mail that I am reproducing below: ![]() Braking produces a force (because the rider/bike combo is in motion and braking means deceleration) that has eventually to act through the front tyre contact patch where it is countered by the force of friction between the road and the contact patch. Since the connection between the contact patch and the rest of the bike is primarily through the fork, a large component of this force travels down the forks. The exact quantum of this force transfer can be calculated by referring to the fig below: ![]() As the forks are raked at an angle to the vertical, the force transferred through them can be calculated as a product of the total force and the Cosine of the angle of application of the force. Here the angle is the 'rake' angle minus 90deg (since the rake angle is measured against the vertical). Assuming a rake angle of 25deg and a braking force of 1N, the force component acting down the forks would be = 1 (N) x Cos(65) = 0.4226. Meaning that some 42% of the braking force shall act through the forks. ![]() Let us assume a ZMA (about 150kg) with a rider weighing 70kg coming to a panic stop. Stock tyres on clean tarmac can give a decelration equal to about 1G i.e. about 9m/sec2 So the total force generated would be like F= M x A = 220 x 9 = 1980N 1980N x 0.42 = 836N = 85kg (appox) So the forks get pressed downwards by a force equivalent to 85kgs. No wonder they get compressed. As you can see, the 'softness' or 'stiffness' of the suspension set-up has no meaning for weight transfer. The 'weight Transfer' is a Force that is generated due to braking. It is just that with a softer suspension, you get a larger deflection of the springs, more dive and so it 'feels' like there has been a LOT of weight transfer occurring. And about Trail Braking: Loading up the front during a turn is not a ‘needed’ thing. It just happens because of braking and also because of the centrifugal force generated during a turn that compresses the suspension. Ideally, a completely unloaded front is the best as all the available traction is there for resisting the slide (the tangential force that wants to slide the bike ‘out’ of the turn). But in the real world, we can only strike a workable balance between the various forces to our benefit. And suspension dive is what the rider needs the ‘least’ during a turn. The ‘quick steering’ benefit is way offset by the detrimental effects of a bottomed out suspension and an excess demand on the traction reserves. In a nutshell:
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Last edited by Old Fox; 07-02-2010 at 01:05 PM. |
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#2 (permalink) |
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Senior Member
Join Date: Feb 2009
Posts: 129
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I cannot help to reiterate a few important points, especially regarding braking
1) Always maintain your brakes. A thumb rule I use is replace your brake liners (drum brakes) at every 8,000 kms irrespective of the 'feel'. Your mechanic might say, "sir aur 2000 kms chalega" but dont put your life on the line for a part which costs less than a premium movie ticket or a pizza. For Disk pads i replace between 10000 and 12000 kms. Again these are cheap. 2)Check and adjust play of the levers (both front and rear brake). In case of the rear brake excess play will make you 'lean' on the brake in emergency braking which can imbalance the bike. 3)Tyres play a very important part in braking by giving appropriate traction. Bald tyres, low tread tyres increase the braking distance exponentially. Replace tyres when the TWI (tread wear indicator) is visible. Most times this will be once a year. 4) In emergency braking conditions and if you are riding with a pillion, remember that the pillion might not have the same reactions as you do and will tend to shift the weight of the bike suddenly. Also as the weight is more the inertia of the bike is higher. With pillion, the best way to brake is to tap the rear brake,quick pull and release on front brake, then apply both together.
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Riding the BULL....(with out the LET)... 2004 Indica DLS|2005 Kinetic Zing 80|2009 HH Hunk Ride Safe...you owe it to the person who will be affected if you didn't My Blog - have fun http://sadugiri.wordpress.com/ |
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#3 (permalink) |
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riding in search of tea stalls
Join Date: Dec 2008
Location: shimla
Posts: 17
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i add...also it is very important that you keep discovering the braking capabilities of the bike as well as yours by testing yourself in different controlled conditions. knowing the technical knowhow only is never enough. slowly push the braking to its best...do not jump to the expected max straight away.
my experience says that you can improve your braking distance(in normal road conditions) by jerking(releasing and applying brakes strongly and in a simultaneous manner).
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no races, no stunts, no limits...simply khopchagiri... |
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#4 (permalink) |
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Chak De Phatte
Join Date: Dec 2008
Location: Mumbai
Posts: 24
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I have noticed that some guys almost always ride with their foot on the brake pedal (because I can see their brake lights glowing). The primary cause of this is a misadjusted brake pedal. Always adjust your brake pedal so that in your normal riding position ( while resting on the foot peg) your foot does not touch it and the pedal is slightly below your foot. I always keep a few cms depth between my toes and the brake pedal. Riding always with the brake pedal pressed will also reduce your mileage.
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If you ride like there's no tomorrow, there won't be. |
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#5 (permalink) |
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Junior Member
Join Date: Mar 2009
Location: Baroda, Gujarat
Posts: 27
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When taking a bike you have never ridden before, move bike at slow speed in open Space/road and test brakes performance before taking it, so no surprises in emergency situations..
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Most motorcycle problems are caused by the nut that connects the handlebars to the saddle |
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#6 (permalink) |
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Mumbiker
Join Date: Sep 2008
Location: Mumbai, India
Posts: 57
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I ride an RE Std 350 and a Yamaha RX-135, both these bikes have front and rear drum brakes, and have very different braking characteristics:
RX 135: The bike is light, accelerates very well and my bike has a continuous issue of loosening brake cable (front). Every now and again (few weeks), I need to tighten the front brake cable and reduce the play in the lever to obtain optimum braking. In spite of a brand new liner, drum and cable, this play is unavoidable, and hence is part of my checklist of maintenance every weekend. The rear brakes are grippy, and if used in isolation, increase the risk of the rear wheel locking and sliding on rubble or muddy roads. On tarmac, the ideal combination of slowing down using front and coming to a halt using front and rear brakes in conjunction is IMO the safest approach. My only bugbear is the tension in the front brake cable, which occassionally loosens considerably, causing the lever to hit the handlebar grip, hence reducing braking ability. RE Std 350: For a 20 year old bike, which is heavy, has poor front drum brakes and rear brakes that are so grippy, they lock the wheel, this bike has its own handling and braking characteristics that set it apart from other bikes in the Indian market. The front brakes are ineffective if not maintained regularly, and many bulleteers notice that on an incline, the front brakes will not hold the bike stationary on their own. The massive weight of the bike and its poor front brakes lead to many riders relying entirely on the rear brakes for stopping, leading to faster wear of the rear brake shoes and liner. To add some bite to the front drum brakes, the drum itself can be scrubbed with emery paper, enabling the brake shoes(poor quality again) to obtain greater friction and improve stopping power. Bulleteers rely on engine breaking to a great extent, and this IMO adds to the character of the bike and the frame of mind required to ride it. In this era of brake disc's, I would appreciate it if riders with older Two-strokes, Thumpers and exotics could detail their bike's unique braking characteristics. In addition to learning about these things, they will also provide an insight into the personality of such bikes, that are found rarely, but when seen always bring a smile to our lips. Cheers, Sriku
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Four strokes move my body, two strokes move my soul. 1988 RE Std 350 (Bull) 1998 RX 135 4-speed (Stella) 2002 Kinetic GF-125 (what was I thinking?) 2008 HH Karizma R (Elsie - sold) |
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#7 (permalink) |
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Junior Member
Join Date: Mar 2009
Location: Vasai!!?? Where the hell is that??
Posts: 11
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I agree with all the aforementioned points, but I was quite surprised to see that the main aspect of braking was left out. Gear checking is an indisposable tool in the art of braking and done properly helps you shed huge amounts of speed in a ridiculous amount of time.
Try doing a 120-0 just using your brakes and then when checking gears, there will be a difference. Synchronize your engine rpm, with the rpm of your gears to your wheel rpm, you will not damage your engine or gears in any way. It goes something like this, you're doing 120 kmph and suddenly a car decides to swerve into your lane, you have already began braking and shedding speed, clutch fully in and rev the engine according to how many gears you want to shift, and then downshit and le go the clutch in a relaxed manner. Super effective technique, although you're still braking as Sunny mentioned above. Coupled together it will inspire a new confidence in your stopping power no matter what the condition of your brakes.
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If you love your bike, let it go, if it comes back you've probably high sided. |
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#8 (permalink) |
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Gimme Fuel, Gimme fire, Gimme that which I Desire
Join Date: Jun 2009
Location: Baroda
Posts: 171
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One more point i would like to add is to apply front brakes in short bursts (it can only come through practice). i personally found it much useful as it avoids the front wheel locking and washing-out. it saved me a couple of times while avoiding crashing into other vehicles and braking simultaneously!
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#9 (permalink) | |
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Senior Member
Join Date: Oct 2008
Posts: 202
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Quote:
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#10 (permalink) | |
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Impossible is Nothing
Join Date: Sep 2009
Location: Thiruvananthapuram
Posts: 450
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Quote:
when at high speeds the initial slowing down (anticipated braking)has to come by shifting to lower gear / gears. the best way to shift down is using the clutch only to shift the gears (shift and release clutch) while applying both the brakes suitably as per the road condition and stoppage required and before full stop pull in the clutch. this way your clutch, gear, front and rear brake will contribute to your braking. 4 in one effect. less wear on the brakes too. |
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