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Great two points, Cobie. Then, there is too-slow / too-little emergency-steering: "Can you steer your bike as fast as your car? If your answer is "no", my next questions are: What business do you have riding in traffic with cars that can out-maneuver you?, and, Ain't that dangerous? The answers, not pleasant ones to swallow, are: none and yes. You lose." - Keith Code http://forums.superbikeschool.com/index.php?showtopic=109

Our foot, via the leverage of the shifter and the selector drum (shift cam), can develop a lot of force on the forks and dogs. Not having been designed for such forces, the shift forks could be permanently bent and the dogs could be worn (rounded): only transmission surgery can fix that. This article explains it: http://www.gadgetjq....ransmission.htm From the TT2's DVD: "Pads are cheap, transmissions are expensive."

Similar, but not quite............... I referred to the attached schematics in my post that try to show the problem of early apex leading to running wide and what your solution of moving the turning point aft does. Did you see those?

Note that the reduction between 1st and 2nd is double than among 3rd and 6th; hence, it requires a stronger blipping. Check this video out:

From TT2: "Turning it too quick will shake the bike or wind you up on the inside." Alfred, Is this what you mean?

I asked because I was not sure if you knew what happens inside the gearbox. Now I see that you know; however, let’s use some numbers to put things in perspective. I couldn't find the specifications for the 2007, but let's use the gear ratios for the 2013 YZF-R6: 6th gear = 1.150 5th gear = 1.286 4th gear = 1.444 3rd gear = 1.667 2nd gear = 2.000 1st gear = 2.583 Downshifting from 6th to 1st, we have different % in which the rpm's of the engine must be increased for an ideal synchronization of the gears at the instant of engaging and for not upsetting the rear tire: 6th to 5th gear = 12% increment of rpm 5th to 4th gear = 12% increment of rpm 4th to 3rd gear = 15% increment of rpm 3rd to 2nd gear = 20% increment of rpm 2nd to 1st gear = 29% increment of rpm That means that you have to blip a little harder for low gears (and again, that is independent of the speed of the bike). However, it is never too much as to induce a wheelie. Normal throttle range is about 90 degrees or 1/4 turn. Once you clutch-in, a little twist goes a long way increasing engine's rpms'. Yes, you should avoid over-rev first and then let the engine die and act like a brake for the rear wheel. Keeping two fingers on the brake lever has helped me fine-modulating my inputs to the throttle during downshift. If you are downshifting for slowing down, then you can allow the rpms' go down gradually after each downshift, so the next blipping takes the engine only up to the initial top rpms more or less. If you are downshifting for more torque (passing), then your engine will turn at sustained higher rpms' after the downshift; hence, don't do it if the engine is high in rpm before the downshift. You are welcome !

Mind elaborating? For example, looking for above during a left turn, the hips should be turned CCW?

Yes, I am advising the first. Can you explain why do you blip? Idle rpms' are whatever rpms' the engine falls down to naturally once it is disconnected from the rear wheel. It seems that it is around 500 in your case (a little too low in my opinion). How many in neutral? The rpms' at which you downshift are not important. What bike do you ride?

Pommerac, The trick is coordinating rpms' of the engine and rpms' of the rear tire at the very moment of engagement of those two sections of the transmission system. Just blipping the throttle not always achieves that coordination: you need to give some gas, or the engine will rapidly slowdown all the way to idle rpms' (faster than the engine of your 250 did). If the engine is at idle and the rear tire is rotating relatively too fast to match that, your "bike actually feels like it jerks and considerably slows down due to engine breaking" when you downshift. In that case, the inertia of the bike forces the engine to suddenly speed up up to the rpm's that correspond with the rotational speed of the rear tire; thing that you should have done via throttle (crack opened) during the downshift.

aslcbr600, As you know, reducing the lean of the bike is about moving the CG of the rider off the center-line of the bike. In sport riding position, our CG is located approximately under our chest and at the height of the belly bottom. Extreme hang-offs don't gain much in moving over that CG, respect to more moderated postures. All the mass of the rider concentrated in that point in space will have the same effect. Your legs and torso together are 6 inches shorter than those of a 6 foot-tall person. Let's assume that the upper portion of your leg, which connects the tank and your CG, is 2 inches shorter. Since while you hang off, that upper portion of your leg is at certain angle, let's also assume that you can locate your CG 1.5 inches shorter than the taller rider can. If you weight as much as the taller rider, let's say 150 lb; and each bike weights 425 lb wet, you can push the CG of the bike to the outside of the curve 0.52 inches less than the taller rider, which in degrees is around 3.5 degrees more of lean for the frame of the bike. Those 3.5 degrees are only significant to the suspension, since the lateral forces on the tires will remain the same, either if you hang-off much or not at all. If the suspension of the other rider is working at 40 degrees respect to the vertical (only direction in which the road bumps work), the suspension of your bike is working at 43.5 degrees respect to the verticals. As csmith12 questioned above, is that little gain worth you over-stretching and adopting any uncomfortable posture, which could compromise your confidence and smoothness? As for using your extended leg as a gauge for lean angle, yes, you will drag knee at a higher lean angle than taller riders, but not for much either.

Mugget, A friend and mentor told me once that when in doubt, I could analyse things in ridiculous extreme conditions. That is what I did in the attached schematic, using AutoCAD, so the dimensions for angles are provided by the software. You can see that I fixed the turn's speed and radius, which gave me a dynamic lean angle (angle between the vertical, the center of the contact patch of the tire and the rider-bike combined center of gravity) of 45 degrees. The differences in tires' cross sections and height of the centers of gravity have been exaggerated in order to obtain clear results. In real life, the differences are not that big: the CG of the upper portion of the body can only change around 3" in height. For a rider of 200 lb on a bike of 400 lb, that change induces around 1/2" of height variation in the combined CG (100 lb upper body / 600 lb combined weight). If we compare a sport 125 and a 1000 cc custom chopper, the cross sections of the tire would have more important influence on the lean angle of the frame of both bikes during identical turns. In summary, high CG and thin tires help the suspension work better because they keep the frame of the bike a little more upright. I would say that a lower CG helps flicking, if we consider the roll-resistant moment of inertia discussed above.

Kruizen, We need to go back to basics: Lean angle is a consequence, not something that you decide directly. Your only decision is speed at the beginning of the turn and how much you accelerate along it. For a turn that traces a constant radius semi-circle, each speed will auto-generate a lean angle. That is the angle at which all the forces that could roll the bike are balanced and cancel each other. Via counter-steering, you could force the bike to abandon that natural angle, but the immediate consequence would be a roll (either to the inside or outside of the turn). Each time that we make our bike trace a semi-circular trajectory which constant radius is bigger than the constant radius of the actual curve, we have an apex. See the attached diagram below. We adopt that bigger radius in order to make the trajectory shorter, to increase our speed some and to complete the curve a fraction of a second earlier. If that bigger radius is constant (ideally, because it is not so for quick flick technique,...........yes, a discussion for later), the speed and consequent lean angle should be constant along the curve (actually, both increase some as we accelerate to keep the 40/60 weight distribution). Max lean angle at apex means that your speed is increasing from entry to apex and then decreasing after apex, which has no reason to be. Yes, as early as possible, depending on road, traffic and visibility conditions. Remember, whenever you are not accelerating moderately along the curve, you are overloading the front tire. The only way to mess up the turn in is by using the wrong point or the wrong entry speed, lean angle has nothing to do with either one. Excessive entry speed = cannot accelerate = overload front tire (even more if you brake or cut the throttle). Insufficient entry speed = everyone passes you. Yes, but with a smooth transition between each step.

Approach #1 has been the winner. Traction is proportional to the weight on the contact patch and the size of that patch. As long as you are braking (decelerating during a turn), you are not achieving the ideal 40 front / 60 rear percents of weight distribution; hence, you are unnecessarily overloading the front tire and setting the suspension off its ideal point of operation. Get done with all the deceleration before beginning of the turn and smoothly transition from deceleration to acceleration while fine dialing your entry speed. After you master that sequence of inputs, you will not need to think much and will concentrate on trying higher and higher entry speeds in order to achieve faster turns. Check this article: http://www.sportride...king_potential/

It does make sense: thank you much, Cobie !

Thanks, Cobie ! I have tried it, but I feel that I am hurting my transmission. I prefer the traditional method of clutch in-blip-shift-clutch out. Why do you think that I do what I do? It seems a timing thing (maybe a SR?) or a compensation habit. Any specific bad consequences?

Trail-clutching. For turns that seem difficult to me, unconsciously, I extend the downshift process into the turn, releasing the clutch slowly for the gear in which I will run the turn. It doesn't happen for easy turns.

Maybe any legal limitation would be too extreme for USA, but some education and limitation on dealer's encouragement to inexperienced riders to buy the fastest machines would help saving some precious lives. In my opinion, two days of MSF basic course (optional in several states) barely prepares anyone to jump into the jungle of traffic. Motorizing that inexperienced person with 60 HP is almost criminal.

Stroker, I have ridden a lot in similar environments out of USA; traffic discipline in Latin America is not better. However, the relatively low speeds (as shown in your posted video) make it a controlled chaos (considering how many crash versus how many share the roads). I can tell you that rule #1 is to slow down as much as is practically possible. As you may know, braking distance is not directly proportional to speed, required distance increases much faster than speed. Hence, 2 km/h less may make the difference between hitting a tricycle or stopping 3 meters earlier than the point of colision. Your reaction time is between 0.8 and 1.0 seconds; less meters are covered in that time if you are moving slower. Rule #2: Stay in the proper gear at all times, so you always have enough torque to spring out of a bad situation, like a truck coming to hit you. For any other situation see rule #1 above. 1. If some one swerves suddenly in front of you, do you counter steer heavily to get out of the way or will you crash if you do that? Yes, you push the handlebar on the side toward which you want your bike to go. Practice that many times, until you can do it while sleeping; that evasive maneuver will save your life one day. If you are not going crazily fast and the pavement is not oily or wet from a first brief shower, the front tire will stick, regardless of how fast and hard you counter-steer. 2. If you are not going to stop in time, is it better to not brake at all but steer away from the vehicle in front of you? Yes, most of the times that works. However, there is always the possibility of hitting that car even if you steer away. Because of that, I have been practicing to reduce the speed of impact as much as possible, before starting the evasive steering away maneuver (never combine both). Braking most be progressive, so the front tire has enough weight transferred onto it to be able to develop maximum stopping power (avoid a panic handful of brake). Note that this requires constant practice on a parking lot or some other quiet paved area. The reason is that you will not be able to think during a life or death situation, you will only have the habits that you have developed with dedicated practice. I know from experience that your brain immediately switches from the reason mode to the instinct mode, there is nothing that you can do to avoid that. The instinct will take over and will command your hands and feet to do what has became a habit; if you don't have developed such habit, either nothing or the wrong action will be commanded. 3. You can't get your knee to the ground on the highway.So how do you steer away quickest from an obstacle? I don't see how the knee and a quick swerve are related. See my response to the question #1. A quick counter-steer is the only way to achieve a quick change of direction. Please, read these excellent articles: http://forums.superb...p?showtopic=109 http://www.msgroup.org/articles.aspx

For street riding, it is painful observing young riders moving way too fast and apparently being unaware of all the potential hazards associated to traffic and road conditions. I am not referring to the semi-unprotected squid that has developed enough skills to pull the eventual stunt on the street; that guy has managed to survive a couple of years of traffic and stunts. I mainly refer to the 18 year old guy on a 600 cc sport bike, having so much life to be lived and testosterone as ignorance and innocence. I am all for limiting the available cc's to young riders for the initial times of street riding.

Assuming that the engine is working at the rpm's that produce maximum HP (since the bike is moving at its fastest reachable speed), when leaning the bike, those rpm's increase due to the reduction of the diameter of the contact strip of the tire. That increment of rpm's move the engine over the performance curve to a point of lower HP (toward the right of the peak of the HP's curve). Since HP = rpm x torque and rpm's did increase, then the torque on the rear wheel got reduced much more than the increment of the rpm's. As the rear wheel is weaker and pushing with reduced thrust, the bike encounters more resistance due to: -The deformation of the rubber of the front tire to keep a circular trajectory. -More weight due to the G induced by the centripetal acceleration (which translates in bigger contact patches). -More aerodynamic resistance due the rider's hand up position during the turn. -Uphill of that turn (as described by Hotfoot above). Those extra resistances consume energy and naturally slow the bike down. Rpm's return back to the point of max HP (peak of the HP's curve), but because the torque available there is still not sufficient to compensate for the increased resistance, the engine regime continues moving back over the performance curve, loosing more rpm's but approaching and eventually reaching the point of maximum torque (peak of the torque's curve, which is around 11,000 rpm for that bike). An opportune downshift from that point, will move rpm's closer to the point of max HP again. Engines of higher cc's and torque have more tolerance to changes in rpm, so the reduction in torque in similar conditions is not so pronounced as for a 250. You may have cornered hard enough, Eirik, its only that you have not done it on a 250.

Other bikes went over that area after this rider, loosing no traction; hence, oil on the track shouldn't have been. It seems to me that he did a downshift right before the fall. It could have been some lowside involved, combined with trail braking. Other bikes started turning much later into the turn.

You are welcome. Yes, you don't want a surprising burst of torque in the middle of a fast corner, while you are opening your throttle to keep the 40/60 weight distribution. Consider that the engine's rpm will increase while you lean the bike and roll on a smaller diameter of the tire. That could have been one of the reasons that led to your unfortunate high-side crash. Your entry speed and gear keep your engine in the "weak" zone of the torque curve. You quick flick and lean the bike and then crack the throttle open, the rpm's grow and suddenly enter the "strong" zone of the torque curve. That way, you may overwhelm the traction of the rear tire by accident, just like you do in a 4-stroke by being greedy with the throttle. In this case, a little twist of the throttle, done at the verge of the "weak" and the "strong" zones, may simply deliver too much torque onto the rear contact patch. Others with more experience will post here soon; just hang in there.

Very welcome to the site, Bex !!! I have been lucky enough to be riding 2-stroke bikes for many years. If yours have a tuned pipe, then you have a lot of power in a narrow band of rpm's and very little out of there. Fine throttle control is your friend and you need to learn to twist that wrist painfully slowly, opening and closing it. The engine has much less rotational inertia and counter-compression than a 4-stroke when you close the throttle; hence, there is no much engine brake effect and changes in rpm's happen faster (the engine is more agile to gain or loose rpm's). Those characteristics make any 2-stroke less flat than a 4-stroke, regarding torque versus rpm; more temperamental, if you wish. Gears are also your friends, because they allow you to keep the crankshaft spinning within that range of rpm's that provide good torque; hence, surprising bursts of torque cannot catch you during critical situations, like extreme lean or coming out of a turn. I would work hard with the gears to keep the engine at top performance at all times, regardless of the speed of the bike, using the throttle as CSS teaches: smoothly, progressively and timely, specially in turns that reduce your available traction.

That is a good question, Eirik. I would say that, for all modern forms of classical motorcycles, the handling and actions are similar to those of the first practiacl bicycles designed and built after the introduction of the first practical pneumatic tire (1888), the rear freewheel, brakes, gears and Bowden cables. Either powered by human muscle, engines or motors, the principle, the physics, the uses, the riding techniques and joy and reward of any cycle have remained more or less the same for more than a century. Competitions of equivalent disciplines for bicycles and motorcycles look alike and demand very similar approach and control skills from the pilots. Diferences in power and weight of each machine may be huge, but gravity and friction acting upon them are the same.

Congratulations, Hotfoot !!! Really amazing achievements, considering the time and effort that your other responsibilities and activities take. "My ultimate goal in life was to make my passion my job and with this position I feel like I'm living my dream."