Lnewqban
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Posts posted by Lnewqban
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Welcome to the site!
There is much to learn here.
My question is, if I had started rolling on,when it started sliding, and picking up the bike with authority, this wouldn't have happened. Am I wrong??Preventing a front slide on the street is much easier than saving one.
That excessive dive may be due to worn springs or insufficient pre-load (but it may be not as excessive as you believe); servicing the suspension and replacing the old fork oil (if older than two years) will improve the re-bounce damping.
Simultaneous accelerating and braking is not a good technique, it just puts more load on the front tire's contact patch; how smoothly and gradually you come out of that cross-control situation has a great influence on the front tire's traction (sudden release of any or both would upset the suspension and the traction margin).
Read these articles by Keith Code:
http://forums.superbikeschool.com/index.php?showtopic=310
http://forums.superbikeschool.com/index.php?showtopic=540
If your front suspension is soft, you should do all your braking while moving in a straight line and not so hard that the suspension tops down; in emergency braking, that top down will be less important than keeping the steering straight.
Some trail braking is OK, if you prefer, but nothing dramatic.
Street riding needs a very different approach than track riding regarding keeping a safety margin and evaluating road, weather and traffic conditions at all times.
Leaning onto the direction of a strong wind lifts the bike and reduces traction in both tires.
Any steel or white paint means much less traction, especially if wet (even invisible condensation).
Less speed would have required less lean angle and wouldn't overloaded the front tire.
I would keep street-riding, but taming the gas a couple of notches down.
Bigger question is....3rd accident in 5 years...2 on road and 1 on track; is there a way of knowing if this pastime isn't for someone?? I mean, I don't give up easily, but how much more discouragement do I need?? Have taken many schools [5 [x] MSF, 3 [x] CLASS, 1 CSS], must not be able to retain much, I now think that not having taken Level 2 with the Slide Bike may have been a mistake.Two road accidents in five years is not uncommon; where there is a will, there is a way.
Maybe your way is more education?
For street riding education, I highly recommend reading "Proficient Motorcycling" by David. L. Hough.
A philosophical question too; if I go forward, is it more encouraging to repair my existing bike, keep it and put "experience" on it, or replace it and have a feeling of "starting over"??I would keep the old bike if in decent condition still (I have a sentimental attachment to my old bikes).
Best!
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Thank you, Brad !
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The last Keith Code's article in MC magazine reads:
"Seven years ago, I designed a rider training program specifically for street riders and to date more than 1000 riders have run through it."
Read more: http://www.motorcycl.../#ixzz2BYP2KLiW
Does this training program still exist?
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Hi everyone!
My wife tells me I have OCD about my riding lol.
We all do have that
Welcome!
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If i want to hold the best line and provide the maximum stability for the bike for some corners ...
I go way above the speed limit imposed on that turn.............
and if I go on the legal limit... I dont feel safe because everything is unoptimized and unstable (brake points,entry speed, quick turn,bike feels less stable etc)
I dont like to speed for safety and financial reasons ; Im a law abiding citizen when possible
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Anyone has a familiar problem like mine and solutions?
No, I don't have that problem.
I have been riding on difficult streets for so many years that I unconsciously adapt my speed to the conditions.
It amuses me many times that the speed I choose is very close to the posted speed, except in areas marked for 20~25 mph (highly enforced).
Maybe is just that most of the speed limits are reasonable here in Florida, where I ride.
On the freeway is different, everybody goes 15~20 above the posted 65 mph (some go much higher); hence, I feel insecure if I try abiding the law there.
For me, the dangers of traffic and distracted drivers have much higher weight than brake points, entry speed or quick turn.
Regarding stability, yes you will feel more gyroscopic effect at high speeds, but it is not difficult to stay stable and in total control at lower speeds when you get used to them.
In your case, I would practice slow and emergency maneuvers in parking lots as much as possible, making them more and more complicated with time.
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This is something that I've been thinking about on and off for a while.... is the supermoto "leg out/backing in" style really the fastest way for those guys to get around a track? I haven't yet tried to get into this discussion on a supermoto forum or with SM riders in real life, but I am guessing it would be quite an... interesting discussion.
Interesting discussion, indeed.
In my opinion, that technique is just an extension of the proper technique on mud.
Steering or countersteering on a loose surface is not as effective as on pavement.
Too much of any and the front tire will dig deeper into the mud, creating a pivot point rather than the desired rolling and steering effect.
Note that what they just point the bike close to into the desired direction by dragging the rear tire and not putting steering load on the front tire.
There is a point at which the rear tire simultaneously regains traction and is in line with the front tire.
If the turn is much more than 90 around degrees, the second part is completed with regular steering at lower speed and with acceleration.
The fastest way for those guys to get around a track?
Maybe yes for mud tires on a slippery pavement track, but certainly not for sport tires on a regular track.
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I think your missing a post here......
I didn't miss the post or the quote.
Sorry, I simply cannot see the blip anywhere in the video, just the simultaneous roll-off / shift that Hotfoot explained as the first step to practice the technique.
I would like to learn how and when the throttle blip should be.
WHEN: The blip happens simultaneously with the shift. If you do it too early, you will feel the bike surge forward, if you do it too late the bike won't shift.
HOW: Blip right when you shift, and just enough to match the RPM to where it would be in the lower gear. You will have to experiment with it to get it right for your bike. Too MUCH blip will make the bike accelerate (not desirable if you are TRYING to slow down for an upcoming turn) and it may not shift.
If you don't blip enough, it just won't shift.
Thank you both very much for your previous and clear responses, Hotfoot and Aslcbr600.
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I think your missing a post here......
I didn't miss the post or the quote.
Sorry, I simply cannot see the blip anywhere in the video, just the simultaneous roll-off / shift that Hotfoot explained as the first step to practice the technique.
I would like to learn how and when the throttle blip should be.
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I want to learn to do this, but it scares me sh**less!
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......... - in a high gear, at low rpm, accelerate, then left off the throttle and RIGHT when you let off, downshift. It should just drop right into the lower gear. After you get that timing, you can go back and add the blip so you can shift while slowing down.
Just to better understand: aslcbr600's video does not show the added blip.
Am I correct?
If so, when exactly the blip takes place?
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..... I want the confidence of going into a particular corner and know that even if I ever needed to really lean this bike over, then I know I can do it. Maybe it is more of a mental issues but as for now, I feel like my skills are limited....
It is important to understand that the bike is leaning exactly what it needs to lean to have a perfect balance of gravitational and centrifugal forces.
Gravitational force or weight cannot be changed.
Centrifugal force depends only on two things: radius of turn and speed.
For the same curve, radius cannot be changed (unless your line can be improved); hence, increasing speed is the only way to increase the lean angle.
Currently, you have a mental barrier of what speed seems to be safe for that particular turn.
As others have explained, simply forcing yourself to overcoming that mental limit and going faster on street roads may get you into trouble (what if you suddenly panic and cross that yellow line at the wrong moment?).
As you practice to ride in a more smoother manner, increased speed will come naturally.
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You are welcome !
Sometimes, not even one hand is necessary, as this video shows after 0:30
http://www.youtube.c...player_embedded
One more thing:
Transferring weight from one tire to the other takes time, because the CG has inertia.
Hence, the normal force on a contact patch can only grow up to the optimum value at certain rate.
Sudden accelerations and decelerations can load the rubber transversely much faster than weight transfer can load it perpendicularly.
As stated by a friend:
"Realize that the tire will take a great load, but it won’t take a sudden load…and so you practice this smooth loading at every moment in/on every vehicle."
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Eirik,
I am not bringing an answer to your problem nor trying to question your piloting skills in any way, just following a logic thought:
Your case is very interesting because you have had similar random results from several combinations of bikes, tires and road conditions.
Among other things, tire grip that resists sliding forces depends on the coefficient of friction and the force that is normal to the road surface.
Centrifugal forces that induce skids depend on the speed of the bike and radius of turn.
Lean angle relocates the bike to balance those forces and can be changed with steering inputs via counter-steering.
If all the above is true and grip fails randomly for the same speed and turn radius, three things may be happening (in a separated or combined way):
1) The coefficient of friction between rubber and pavement suddenly changes only for the point at which the skid happens (roughness, sand, liquids, etc.).
2) The normal force gets suddenly reduced (and poorly compensated by deformation of frame, suspension and tires) for the point at which the skid happens (front-rear re-distribution of weight via throttle or brake input, road irregularities).
3) Additional load is added to the centrifugal force for the point at which the skid happens (steering correction, braking, acceleration).
For #1 there is no much you can do on the street but slowing down in turns enough to create a safety margin.
For #2, a painfully slow throttle input may help, as well as avoiding braking on the turn and experimenting with reducing air pressure up to a safe value that does not cause over-heating of the tires.
For #3, steering with the inner hand mostly (avoiding fighting of both hands and multiple little corrections during the turn).
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........As far as I know you can do clutchless downshifts on any bike. I use clutchless downshifts on all my bikes, including my old 1988 YSR50, my cruiser, and my dirtbikes. I've never had to replace a clutch, and never had any transmission issues...........
I stand corrected.
I will have to experiment with my bike.
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Let's hear what you've noticed has changed about your riding when you got a newer, or just different, motorcycle!
May be because I don't ride to my limits in the street, but different motorcycles and HPs' have not made me notice any changes in my riding.
Brake performance has been the most difficult thing to learn and get used to from each bike.
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.............I didn't really consciously work on anything new (in terms of the CSS exercises), but did find that I was consistently very relaxed at the bars and through my arms and shoulders. The lean angles don't spook me anymore, so I am not tensing up at all really...........
That is a better measurement of your progress than reduced times,...........and much more useful in street riding.
As discussed at the beginning of this thread, there was never a need to fall.
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Hotfoot,
I believe that your explanation works for bikes that have some mechanism to help the shifting of gears without using the clutch, like most modern sport bikes have.
For simpler bikes, clutch-less downshift can't work for the same reasons explained above.
Without a regular clutch, there is a solid transmission from crankshaft to rear wheel, any blip of the throttle will increase torque of the engine, and rpms' of the connected gears and wheel alike.
By clutching-in plus blip (old fashion way), the gear to be engaged (engine side) is accelerated to match the spinning speed of the wheel side gear.
I may be wrong, but clutch-less downshifting can't be accomplished for any old standard motorcycle.
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The book explains that in more detail.
No rear brake.
The idea is to perform the gross reduction of speed first and then fine tune your entry speed.
Let's say, you have three seconds to reduce from 80 mph to 50 mph, which you know is your best entry speed.
Use the first second to go from 80 to 62 (reduction of 18 mph in one second) and the other two seconds to go from 62 to 50 mph (reduction of 6 mph in each second).
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riding on the road we're not familiar with, where the turn hidden behind the hill and decrease, is it safe to do more counter steering to compensate with decrease turn? or is it any other way to handle this situation?
It is safe if you still have a safety margin regarding traction (you are not at maximum lean).
If you have no cushion angle, just read this post:
http://forums.superbikeschool.com/index.php?showtopic=3438&view=findpost&p=28191
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Maybe something like this?:
Joke aside, I believe that the response to your questions is all about the dynamics of the center of gravity or mass of the bike.
This CG is located between both wheels and somewhere under the seat.
For the first question:
As soon as the rear tire starts lifting up, the inertia of the CG will force it to rotate around the front tire's contact patch (because it is braking or slowing down).
Hence, that won't happen only if the CG is in line with that contact patch.
Imaging a rod (the bike while braking hard) being balanced vertically on the palm of your hand (the front tire patch).
As long as the CG of the rod is in vertical alignment with the point of support, the rod will not fall.
If the rear tire has traction, it is like you are holding the top of the rod with your other hand.
For the second question:
Also consider that the contact patch of the front wheel is not on the axis of the steering, due to the caster.
Because of that, any steering input will move that contact patch respect to the CG (to gain or to loose stability).
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Imagine two straight lines connected by a curve of constant radius.
Both points of transition represent two perfect quick flicks.
Any lazier entering and leaving flicks than the previous ones will deform the transition points and the curve, decreasing the minimum radius (compared to the previous one).
That reduced radius will force a bigger lean angle (or its alternative: a slower curve speed).
The trick of a big steering input while the bike falls into and comes back from the max lean angle is that many degrees of turning are achieved in the process.
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.........
After that, I really concentrated on the "throttle rule" (rolling on the throttle slowly but constantly, once cracked open, to maintain slight acceleration). I got reasonably good at this. Of course I could almost always have opened it up earlier, but the important thing is that I was basically never doing the SR roll off thing - maybe twice during the whole day, and even then only very mildly.
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So, my "lean faith" has definitely increased.
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Can't wait for the next outing to try to advance a bit more. Thanks everyone for your help!
We have been waiting for this positive report.
Very well done!
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How does one use more lean angle if its before the apex? Care to elaborate?
Wongster,
Every time that you are leaning more and more during a turn, you are reducing more and more the radius at which you are turning; hence, your line is describing a reduced radius turn (even if the actual turn has a constant radius).
Watching the video, one can see that you just reached the limit of traction of your rear tire due to excessive lean angle.
For the same speed, the lean angle depends only on the radius of the turn.
Increasing that radius is all that the techniques explained above try to achieve.
If the three bikes were moving at about the same speed, why the other two made the turn?
Check what the biker ahead of you did differently and compare it to the attached schematic.
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You found it inside the front tire.
Front Washout
in Cornering and Techniques
Posted
Simultaneous use of rear brake and throttle is a common and recommended practice in Moto Gymkhana for tight maneuvers.
Clutch is left out of the equation for simplicity.
Trying to accomplish those maneuvers with throttle alone, keeps the engine too close to a jerking condition that would upset the maneuver.
If interested:
http://amgrass.com/f...hniques-clutch/
Note the brake light and the clutch lever in this video: