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Is Sliding Required To Be Fast?

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I’ve spent a lot of time contemplating this particular topic, and it’s become all that much more significant as I am now seriously considering doing a 2-day event at a bucket-list location 2000 miles away (Laguna) that requires that I rent a motorcycle for said track day. The core of my dilemma is my belief that to go FAST a rider needs to approach a threshold of control/grip that tells him that any faster would result in the bike crashing. In my mind, for a half dozen MotoGP riders to qualify within a half second of each other requires that they are pushing their bikes/tires to a tangible REAL limit. It’s not arbitrary or a gray area, it is known (and felt) by each of those top riders who dance on that tightrope of control. Riders that exceed that limit either tuck or highside. Everyone else, from the bottom of the grid to the weekend trackday warriors, is either suffering from an inferior setup or machine, or is pussy-footing around the track because of their fear of falling (damaged bike, end of trackday or race, or injury).

 

So, for me I’m looking at forking out a good amount of money to run an iconic track, on a rented motorcycle, with top notch instruction. The presumption is that a part of that money will going towards teaching me skills that will make me faster. If I was riding my own bike (dedicated trackbike) I could easily envision a fruitful experience. However, put me on a $15,000 motorcycle with a $2500 damage waiver, and my riding attitude and tolerance for risk will be much different. Will I be willing to tip toe towards that limit on somebody else’s bike? Not likely. (oh, and btw where exactly IS that limit...)

 

Which brings me back to the fundamental question – if the fastest way around the track is at the edge of control, how do you teach that? (I know there’s a “slider bike”) Is that “limit” zone wide enough that skillful riders can approach it, enter it, and with the bike sliding through the turn, maintain control throughout? For an intermediate level, or even advanced level rider, that doesn’t really occur. We build speed, one trackday at a time, and just about the time we’re feeling pretty damn confident – yikes! and we have a little ‘moment’, or actually drop the bike.

 

For me I think getting faster means being able to be comfortable with the idea that those moments MIGHT occur, and having the skills and reaction to catch it before it goes wrong. I’m not trying to become at racer, but wondering if that sort of thing is teachable and how it can persist (finding the limit on a special BMW slider bike is one thing, but what about your own bike, on a different track???).

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For me I think getting faster means being able to be comfortable with the idea that those moments MIGHT occur, and having the skills and reaction to catch it before it goes wrong. I’m not trying to become at racer, but wondering if that sort of thing is teachable and how it can persist (finding the limit on a special BMW slider bike is one thing, but what about your own bike, on a different track???).

 

At the Superbike School you will absolutely learn skills that will help you exactly as you described above - knowing what sort of things COULD happen, how to anticipate undesirable outcomes, and the skills to deal with them if they occur. Most importantly you will improve your ability to predict and CONTROL what the bike - ANY bike - will do.

 

For example, you will learn how to make the bike handle more predictably, how to maximize your traction in all situations - including dealing with low traction conditions and how to compensate for a poorly set up suspension - and also learn what causes slides, how to avoid them, how to deal with them when they occur, how to achieve maximum braking without locking up the tire and how to deal with it if it does lock up, and much more.

 

The skills will absolutely translate to other bikes and other tracks.

 

Yes, you may find that you don't want to ride at the absolute limits of traction on a rented bike, but as you will find out in the first few minutes of class, it is quite difficult to LEARN anything when riding at your absolute limit anyway, so part of CSS is riding a bit below your absolute max pace, so you have some attention left over for learning new skills and observing results.

 

You will not be asked to maintain a certain set pace, or match the pace of other riders - you will just be asked to ride at a pace that is comfortable for you, a pace where you can learn - for some riders that is slow and cautious, for others it is quite fast, but your coach will be looking for you to ride at a pace where you are in control of the bike, able to do the drills, and are making improvements.

 

As for whether you have to slide or ride at the limit to go fast... well, as you have no doubt observed, you can often see a rider who is sliding all over the place get passed easily by a rider who doesn't seem to slide at all. That can be a skill issue (poor throttle control, rough inputs, and tension can all cause sliding even at a very moderate pace), but also there are many styles of riding. Some riders prefer the bike to feel loose and slide around, and others want it to feel planted and solid. The amount of sliding also depends on tires and setup, and a good part of riding at that top level is getting the bike set up properly for the rider, so the rider can make best use of his/her skill set.

 

I have no doubt that CSS will help you improve your riding, get better control of the bike, understand more about how the bike works, etc., and that the skills will translate to wherever and whatever you ride at home.

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I have no doubt that CSS will help you improve your riding, get better control of the bike, understand more about how the bike works, etc., and that the skills will translate to wherever and whatever you ride at home.

 

 

thanks for the reply. signed up today for Apr 6-7. :D

 

but to continue the dialog re the topic, your reply suggests that sliding is in fact a required skill set as you slice away at those last few seconds. and I consider myself one of those "planted and solid" type feel riders. assuming that I've got all the basics squared away (which I don't), i'd imagine that letting the bike get loose is something that i'll need to learn eventually. I don't expect to flirt with that on my rented S1000RR, but having the knowledge of where it is and how to ride through it is probably one of my biggest quandaries. although having my own trackbike I can throw down the track is convenient, i'd actually prefer NOT to!

George

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With good technique, on a dry track with a bike with functional suspension and good tires, sliding is not necessarily a sudden and catastrophic event. As long as the riding technique is good (especially throttle control), sliding can be approached very gradually. There is an article in the "Articles by Keith" section called the Bands of Traction that you might find helpful, it talks about the various ways the tire can feel at different levels of riding.

 

There is another article he wrote recently and hasn't released yet that talks about traction and points out that the tire is ALWAYS slipping, as you corner - it is DESIGNED to do so. So there is actually a gradient there, from the slip that you don't feel at all, to the slightly squirmy tire, and all the way up to the type of slide that gets the back end sideways. I asked him about that article and he said he'd get it posted in the next few days so you can have a chance to read it.

 

It's really awesome to watch Will, the school mechanic, ride the school's slide bike. He can get in a circle and just run that back tire through its paces - from no visible slide all the way up to smoking and spinning, and everything in between, all without losing control of the bike. Watching him do that is a good reminder that sliding the tire does not have to be like falling off a cliff - it can be done a little, or a lot, and anything in between; the trick is learning good technique so that you can be in control of the bike.

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It's really awesome to watch Will, the school mechanic, ride the school's slide bike. He can get in a circle and just run that back tire through its paces - from no visible slide all the way up to smoking and spinning, and everything in between, all without losing control of the bike. Watching him do that is a good reminder that sliding the tire does not have to be like falling off a cliff - it can be done a little, or a lot, and anything in between; the trick is learning good technique so that you can be in control of the bike.

 

 

Can I sign up for a level 4 and just do the slide bike all day :D

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It's really awesome to watch Will, the school mechanic, ride the school's slide bike. He can get in a circle and just run that back tire through its paces - from no visible slide all the way up to smoking and spinning, and everything in between, all without losing control of the bike. Watching him do that is a good reminder that sliding the tire does not have to be like falling off a cliff - it can be done a little, or a lot, and anything in between; the trick is learning good technique so that you can be in control of the bike.

 

 

Can I sign up for a level 4 and just do the slide bike all day :D

 

 

Make that two people wanting to do that. :)

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Traction is a concern of mine as well. The Datalogger on my BMW is quite helpful for being able to "see" the limits of traction that I have. I have been on a bike that was sliding and not equipped with TC. The training that I got at the Superbike School made surviving the back stepping out second nature and a complete non issue. Simple basics such as throttle control and remaining loose on the bike seem pretty simple but pay dividends when things aren't going according to plan.

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Traction is a concern of mine as well. The Datalogger on my BMW is quite helpful for being able to "see" the limits of traction that I have. I have been on a bike that was sliding and not equipped with TC. The training that I got at the Superbike School made surviving the back stepping out second nature and a complete non issue.

Datalogging may reveal that the back tire is losing traction (front/rear speed bias), but there's really no way to electronically detect the front sliding. And THAT'S the crux of this post. With modern traction control strategies you can get the back end a bit sideways without much drama, and having tracked a low tech V twin liter bike for the last several years I've become accustomed to some sideways attitude on corner exit, but I'm WAY more interested in cornering: how much braking can you carry into the corner, and then how hard (fast) can you corner before you run out of traction. That last bit is the intriguing part. As a "planted and solid" type rider I THINK that i'm approaching the point at which my tires can no longer support the cornering load. It's a gut estimate. But if I take that corner faster and faster as my confidence increases, at some point things are going to change... hopefully the feedback from the bike is subtle but obvious and I get a sensation of sliding that I can recover from. Or, if I'm really comfortable, I can ride in that "slide zone" which is where I presume the top 1% ride. If the slider bike can teach that, i'll be tickled pink!

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It's a great topic and one I've been intensely interested in because it does seem one has to contend with a certain amount of pushing the front and getting sideways with the back end if you really want to be at the front of the group.

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I see it as a circle.

 

When one first tries to ride a 2 wheeled vehicle, the perception of traction is a bit "sketchy". As experience grows so does that acceptance of available traction. The rider then learns to maximize traction per conditions through purposeful inputs that result in predictable and desired outcomes.

 

Fast forward, to advanced group track days and racing....

 

The same feelings of loose traction return as a rider approaches the edge of the envelope or the combo of rider/bike/tarmac. To win a race do you have to be "fast"? No, you just have to be faster than 2nd place. One can win while being 10 seconds off lap record pace while completely in control, no major slides or any strange pushing or skips from either the front or the back. Other times, you have to ride at your very best and to the very edge of one's abilities to hold a position in the lead group. It's these days where sliding and pushing occurs, because fast is relative to your fellow track occupants "that day". Honestly though, there is always a bit of slippage here and there, most of it goes unnoticed. Other days, the bike is more vocal than a drama queen. So one must ask themselves, if the bike didn't change.... what did?

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I have no first hand experience, but have read and heard a lot of interviews with world class riders. Some describe the race winning pace as riding on marbles. I don't think you will win an AMA Supersport or Superbike race without being able to slide the tyres. Nor do I believe you stand a chance of winning a race at that level if you have any fear of doing so. Hotfoot and the other coaches can probably give you an idea about lap time differences between tyres sticking solidly and tyres sliding, but I suspect the difference is rather small, maybe 2-3 seconds per minute. Now, how many of you are at a level where you are 2-3 seconds off the pace in AMA Superbike races?

 

Go to school, try and learn as much as you can, improve gradually and if you have what it takes, sliding the tyres will eventually come naturally as a result of becoming blindingly fast. For the vast majority, though, this simply isn't likely to ever become an issue, as a glimpse at the student lap times will show.

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Traction is a concern of mine as well. The Datalogger on my BMW is quite helpful for being able to "see" the limits of traction that I have. I have been on a bike that was sliding and not equipped with TC. The training that I got at the Superbike School made surviving the back stepping out second nature and a complete non issue.

Datalogging may reveal that the back tire is losing traction (front/rear speed bias), but there's really no way to electronically detect the front sliding. And THAT'S the crux of this post. With modern traction control strategies you can get the back end a bit sideways without much drama, and having tracked a low tech V twin liter bike for the last several years I've become accustomed to some sideways attitude on corner exit, but I'm WAY more interested in cornering: how much braking can you carry into the corner, and then how hard (fast) can you corner before you run out of traction. That last bit is the intriguing part. As a "planted and solid" type rider I THINK that i'm approaching the point at which my tires can no longer support the cornering load. It's a gut estimate. But if I take that corner faster and faster as my confidence increases, at some point things are going to change... hopefully the feedback from the bike is subtle but obvious and I get a sensation of sliding that I can recover from. Or, if I'm really comfortable, I can ride in that "slide zone" which is where I presume the top 1% ride. If the slider bike can teach that, i'll be tickled pink!

 

 

I'm not really sure that's accurate about the Datalogging. The 2d system that is on my BMW's provides front and rear wheel speeds independently in two seperate data channels. The Slip Rate metric is a percentage calculated by the difference in speed from the two wheel sensors. I'm pretty sure if the front starts sliding it will change speed and get lumped into the slip rate metric. In addition to that you could observe the data trend in speed between the wheel speed channels independently to see them "letting loose". If you wanted to get super anal there's an add on for the front and rear shock that could show you their travel. Suspension that's topped out or bottomed out could reveal a loss of traction as well as lots of sudden changes in the suspension's position where it does not correlate to the track's surface (an overlay with a lap where you did not loose traction). You could literally observe the bike becoming "unsettled" in the suspension from the data. All of these data points observed together could give you a pretty good idea of what's going on.

 

Possibly the most important thing in analyzing data is knowing what you are looking at and knowing exactly what it means. I'm certainly not to that point yet but I know where I would start looking if I thought the front end was pushing. I also know some people to ask if I really wanted an explanation to a sudden loss of traction in the front.

 

I do however agree with your point. Knowing how to react when the bike is sliding is the most important skill. The data can tell you what happened but only after it's happened when you have pulled the data off the bike and are looking at it on a Laptop. That's not really useful in real time when you are on the bike in the middle of a slide. It's very useful for understanding the limits and pushing them safely though. Being able to correlate that "feeling" with actual data is incredibly useful. These systems exist because the professionals found them useful. Luckily for us they are starting to become available in the consumer market. They are surprisingly advanced considering their low cost relative to what they originally cost in the racing world.

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Hotfoot and the other coaches can probably give you an idea about lap time differences between tyres sticking solidly and tyres sliding, but I suspect the difference is rather small, maybe 2-3 seconds per minute. ...For the vast majority, though, this simply isn't likely to ever become an issue, as a glimpse at the student lap times will show.

 

it would be interesting (but very difficult) to inspect a student's lap, and compare the cornering G loads against the available tire traction. Although gathering the load data is possible with GPS based lap timers, knowing what the theoretical maximum available traction isn't easy. But if you did have reliable values, you could look at your combined acceleration (lat plus long) in G's, and then with a little algebra you could compare that to the tire's available coefficient of friction. That last part is tricky, but can be estimated at 1.2-1.4 for a properly warmed up performance tire. That means a capable rider should be able to push his bike to about 1.4 Gs before he/she starts to feel the limit of adhesion. Theoretically. ;)

 

If you COULD do this analysis, you could see how close you were to the edge and how much cushion you had. What i'm sure you'd find is a rider may be very close to that limit on some corners (possible the corners that he/she is in danger of crashing on), and on others have quite a bit of cushion. For the non-top-1%, it depends exclusively on your comfort level at that particular corner. For the fast guys, they can push INTO the slip zone and stay there. But for everyone else, it's uncharted territory.

 

My point is that "novice" riders don't know where that limit is (could be close, could be far). I'm not looking to line up against Marquez, but as I develop my riding abilities, by definition I will become faster, and my frequency with flirting with sliding is going to increase. That makes me uneasy.

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The 2d system that is on my BMW's provides front and rear wheel speeds independently in two seperate data channels. The Slip Rate metric is a percentage calculated by the difference in speed from the two wheel sensors. I'm pretty sure if the front starts sliding it will change speed and get lumped into the slip rate metric. In addition to that you could observe the data trend in speed between the wheel speed channels independently to see them "letting loose".

you could be right, but in my mind the challenge in measuring front wheel slip is that it's not really a longitudinal speed differential calculation since the front wheel doesn't really slow down, but rather detecting a departure from the intended longitudinal direction (a sudden, slight lateral movement of the front wheel with respect to the bike's expected path). I don't know how you could calculate that. but then again i'm a little hung over. :wacko:

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The 2d system that is on my BMW's provides front and rear wheel speeds independently in two seperate data channels. The Slip Rate metric is a percentage calculated by the difference in speed from the two wheel sensors. I'm pretty sure if the front starts sliding it will change speed and get lumped into the slip rate metric. In addition to that you could observe the data trend in speed between the wheel speed channels independently to see them "letting loose".

you could be right, but in my mind the challenge in measuring front wheel slip is that it's not really a longitudinal speed differential calculation since the front wheel doesn't really slow down, but rather detecting a departure from the intended longitudinal direction (a sudden, slight lateral movement of the front wheel with respect to the bike's expected path). I don't know how you could calculate that. but then again i'm a little hung over. :wacko:

 

 

I agree with you there. For my data analysis abilities it would be very tough if not impossible to see. It might even be a challenge for someone who has a lot of experience. Observing multiple channels and how they relate to one another might give you the picture though. My bikes are not equipped with DDC but the DDC equipped bikes could also give lots of hints as well such as sudden changes to the dampening settings that don't normally happen in that corner with a data overlay from a "non sliding' lap. Reading the data is a bit of an art. With all of the sensors my guess is at least one or two of them might detect "something" that could tell you something useful.

 

My mechanic who's a former race champion took my bike for a test ride and had a bit of fun. I was able to see his fun and later had fun chastising him for it (he knew I was joking). Here's a screen shot from one of the several of the wheelies he performed on the bike with the slip rate going ballistic. It's the aqua colored line. His requested throttle is orange and bike provided throttle is blue (wheelie control coming in). The data is just raw but if you look at the data together you can put together what happened. The two red lines are the front and rear wheel sensors and the green line if I remember correctly is RPM. You can see the bike's wheelie control working and ruining his fun. :)

 

opie.jpg

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Sorry for going off tangent with the data. So here's an interesting observation that might be wrong due to my point of view (a non racer).

 

If you are seeing front end push would you not be then "charging" the turns and sacrificing your exit speed as a result?

 

I'll agree that some level of sliding is probably needed when everyone else is doing it (you need to keep up). Some sliding though to me seems like it's slowing you down rather than giving you the speed you are looking for. Is front end sliding useful in the grand scheme of things for going fast? That's an actual question rather than one to make a point. :)

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I believe it was DuHamel who pushed the front around a certain bend and then,just before crashing, opened the throttle to save the day. Every lap. He made up IIRC 1.5 seconds on the corner/section alone. This was cirka 1973. 10 years later, Spencer was doing the same thing around most(?) corners and since he was winning so much, others tried the same. Lawson and Rainey commented that they couldn't tell why, but that lap times dropped noticeably once they began copying Spencer.

 

Typical Spencer riding

Spencer_zpsda3a81f0-1.jpg

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I suppose that's one unique incentive to get on the gas early. :)

  • Haha 1

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Traction is a concern of mine as well. The Datalogger on my BMW is quite helpful for being able to "see" the limits of traction that I have. I have been on a bike that was sliding and not equipped with TC. The training that I got at the Superbike School made surviving the back stepping out second nature and a complete non issue. Simple basics such as throttle control and remaining loose on the bike seem pretty simple but pay dividends when things aren't going according to plan.

 

having a bike that behaves predictably also helps ; In the realm of COG, I try to make my bike as mass centralized as possible and the left and right behaving properly when in a slide

 

try it with an analogue bike , do a 40-0 deceleration with the back brake only. Alot of bikes will step out either left or right because the mass of the bike isnt inherently balanced

 

(the CB400 sans ABS will nearly always skid to the side of the exhaust )

 

As my bike doesnt have any electronics whatsoever , i add weight to the opposite side of the slide/skid to make the back wheel "wiggle" when flooring the back brake paddle instead of skidding slightly to the right

(my can is on the right fyi)

 

multiple white line slides later and Im not even spooked anymore , slides just nibble into the $10 of attention for me.

 

 

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With good technique, on a dry track with a bike with functional suspension and good tires, sliding is not necessarily a sudden and catastrophic event. As long as the riding technique is good (especially throttle control), sliding can be approached very gradually. There is an article in the "Articles by Keith" section called the Bands of Traction that you might find helpful, it talks about the various ways the tire can feel at different levels of riding.

 

There is another article he wrote recently and hasn't released yet that talks about traction and points out that the tire is ALWAYS slipping, as you corner - it is DESIGNED to do so. So there is actually a gradient there, from the slip that you don't feel at all, to the slightly squirmy tire, and all the way up to the type of slide that gets the back end sideways. I asked him about that article and he said he'd get it posted in the next few days so you can have a chance to read it.

 

It's really awesome to watch Will, the school mechanic, ride the school's slide bike. He can get in a circle and just run that back tire through its paces - from no visible slide all the way up to smoking and spinning, and everything in between, all without losing control of the bike. Watching him do that is a good reminder that sliding the tire does not have to be like falling off a cliff - it can be done a little, or a lot, and anything in between; the trick is learning good technique so that you can be in control of the bike.

 

The traction article is posted now, here:

http://forums.superbikeschool.com/index.php?showtopic=4275

 

It's a good read and a nice reminder that a certain amount of slippage of the tire is always happening.

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Crash.net:

Dirt track really seems to have made a resurgence as far as training for the top grand prix riders?

 

Daryl Beattie:

It gives you that feeling and ability to work with the bike under you and gain confidence. Again it's about the basics. So much has changed since the days of Barry Sheene, in terms of the tyres and electronics, but the guys now are certainly tucking and sliding a lot. Dirt track does an enormous amount for that.

 

You can see Marquez's ability on dirt track especially. The amazing thing for me is that he rides his MotoGP bike like he rides the dirt bike. His feel and ability to do that is unbelievable.

 

Full interview http://www.crash.net/motogp/interview/212870/1/exclusive-daryl-beattie-qa.html

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