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The front lifts when throttle is rolled on, and lightened. Is this as a good a turning option as with a little weight on it, from off gas, or very slight braking?

 

C

Again, you're saying throttle rolled on, I'm not. I'm saying constant throttle, ie. not accelerating, AKA Maintenance Throttle. Acceleration is what causes the lift, not drive.

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The front lifts when throttle is rolled on, and lightened. Is this as a good a turning option as with a little weight on it, from off gas, or very slight braking?

 

C

Again, you're saying throttle rolled on, I'm not. I'm saying constant throttle, ie. not accelerating, AKA Maintenance Throttle. Acceleration is what causes the lift, not drive.

 

Held steady would be better than rolled on, but it still makes the bike run wide at turn entry (wider than the arc it would take off throttle), and this creates adjusting/adding more lean angle later in the turn. So, the bike is leaned over further than needed, for the same speed. Make sense to you?

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The front lifts when throttle is rolled on, and lightened. Is this as a good a turning option as with a little weight on it, from off gas, or very slight braking?

 

C

Again, you're saying throttle rolled on, I'm not. I'm saying constant throttle, ie. not accelerating, AKA Maintenance Throttle. Acceleration is what causes the lift, not drive.

 

Held steady would be better than rolled on, but it still makes the bike run wide at turn entry (wider than the arc it would take off throttle), and this creates adjusting/adding more lean angle later in the turn. So, the bike is leaned over further than needed, for the same speed. Make sense to you?

If you begin the turn in at....say 60mph off-throttle versus 60mph on throttle, why would it make any difference in the turning arc? After this turn is executed, who would be able to got the WOT sooner?

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If you begin the turn in at....say 60mph off-throttle versus 60mph on throttle, why would it make any difference in the turning arc? After this turn is executed, who would be able to got the WOT sooner?

 

We see guys running wide at turn entry all the time (really) and then they pay for it in the middle or the end, so, yeah, think it does make a difference and you don't have to be doing even 60. But, try it, see what you notice.

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If you begin the turn in at....say 60mph off-throttle versus 60mph on throttle, why would it make any difference in the turning arc? After this turn is executed, who would be able to got the WOT sooner?

 

Keith has some very good diagrams and explanations in Twist II about this exact point.

 

Read up on the "hook turn" and the idea that the faster you get to full lean the less you need to lean for the rest of the turn.

 

With the front compressed, the the steering angle is steeper, hence the turn in is sharper. Hence, your flick or hook will be tighter and, off gas, you travel less distance than on gas while turning in, hence, by definition, a tighter turn in and less lean angle needed and more speed potential for the rest of the turn at lean.

 

Check it out.

 

PS - We've done the experiments you suggested, ie. trying the turn both on and off gas at turn in... for several decades now. Really. We aren't just guessing or playing what if games. We know the answer.

 

Just trying to help.

 

r

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PS - We've done the experiments you suggested, ie. trying the turn both on and off gas at turn in... for several decades now. Really. We aren't just guessing or playing what if games. We know the answer.

Now this is something more along the lines of what I was looking for.

 

Truthfully, I agree with Mr. Code's work, but I believe that anything held as truth should be able to withstand scrutiny. If it holds true it can be proven at no length of time.

 

Can we consider this for a moment:

 

What are the forces that predict the turning arc of a motorcycle?

If we use a given speed and lean angle and use the same turn-in speed, why would the same rider not have the same arc through a turn?

What other variables are there in a turning arc?

 

What is required in order to change the steering angle?

 

Thanks guys for working this through with me.

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What are the forces that predict the turning arc of a motorcycle?

If we use a given speed and lean angle and use the same turn-in speed, why would the same rider not have the same arc through a turn?

What other variables are there in a turning arc?

 

What is required in order to change the steering angle?

 

Thanks guys for working this through with me.

 

 

If the front of the bike is compressed some, then the bike will turn quicker.

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PS - We've done the experiments you suggested, ie. trying the turn both on and off gas at turn in... for several decades now. Really. We aren't just guessing or playing what if games. We know the answer.

Now this is something more along the lines of what I was looking for.

 

Truthfully, I agree with Mr. Code's work, but I believe that anything held as truth should be able to withstand scrutiny.

Absolutely. Couldn't agree more. I'm suggesting you DO the experiments YOU yourself suggested. I wouldn't ask you to take my word for it at all. Of course, I suppose that is going to be a little difficult without a closed course race track, a video camera and a stop watch. Or a grid full of other bikes to race against so it becomes plainly obvious when and where other bikes are passing you.

 

Can we consider this for a moment:

 

What are the forces that predict the turning arc of a motorcycle?

If we use a given speed and lean angle and use the same turn-in speed, why would the same rider not have the same arc through a turn?

What other variables are there in a turning arc?

OK, I think the point you are looking for is that, all other things being equal (tire profile, wheel diameter, rider inputs, etc), the steering head angle, and front geometry in general, determines how much the front wheel is turned in at lean, hence, the arc the bike travels at lean. This geometry also determines the degree of stability or instability of the front end, hence, the potential speed of the flick or turn in process. This is why sportbikes have the geometry they do as opposed to looking like, say, a Harley.

 

What is required in order to change the steering angle?

I'm so glad you asked that question, Jay. Like Cobie said, being off the gas compresses the forks and decreases the steering head angle or makes the front end steeper. Basic geometry teaches us that the sum of the angles of a triangle remain consistent. If you shorten one side of the triangle, you increase one angle and decrease another. In this case, the angle between the steering head and vertical decreases, and the angle between the steering head and horizontal (ground) increases. Sometimes it helps to draw yourself a picture or diagram to see the relationships.

 

Thanks guys for working this through with me.

 

Glad to be of service, Jay.

 

racer

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Absolutely. Couldn't agree more. I'm suggesting you DO the experiments YOU yourself suggested. I wouldn't ask you to take my word for it at all. Of course, I suppose that is going to be a little difficult without a closed course race track, a video camera and a stop watch. Or a grid full of other bikes to race against so it becomes plainly obvious when and where other bikes are passing you.

 

 

OK, I think the point you are looking for is that, all other things being equal (tire profile, wheel diameter, rider inputs, etc), the steering head angle, and front geometry in general, determines how much the front wheel is turned in at lean, hence, the arc the bike travels at lean. This geometry also determines the degree of stability or instability of the front end, hence, the speed of the flick or turn in process. This is why sportbikes have the geometry they do as opposed to looking like, say, a Harley.

 

 

I'm so glad you asked that question, Jay. Like Cobie said, being off the gas compresses the forks and decreases the steering head angle or makes the front end steeper. Basic geometry teaches us that the sum of the angles of a triangle remain consistent. If you shorten one side of the triangle, you increase one angle and decrease another. In this case, the angle between the steering head and vertical decreases, and the angle between the steering head and horizontal (ground) increases. Sometimes it helps to draw yourself a picture or diagram to see the relationships.

 

 

Glad to be of service, Jay.

 

racer

I stated earlier that I made a major change to my cornering technique in search of better results. And so, yes I've tried both ways. My best results have been going in with some gas on, quickly get to max lean and rolling on the throttle through the apex and then getting to WOT as I pass apex and get to the exit with my eyes on the next entry point.

 

It's pretty obvious that being off the gas increases steering angle, but that's due to parasitic forces, not just "being off the gas", true? Compare ideal vehicle to real-world and I think you'll agree.

 

When I watch racing on TV, I like seeing the telemmetry data onscreen almost as much as hearing the engines as the riders go through the corner. Seems to me that they're keeping some gas on.

 

May I humbly ask dear Sirs, is the technique the same for a rider on a 2008 CBR1000RR versus a 2003 SV650? How about an RS125? On the superbike you want to get it turned, pointed, stood up and on the gas, right? 125: Cornerspeed. Where do they differ?

 

Why does a rider like Sofuouglu do well on a supersport machine and not so on a superbike? Why does someone like Jonny Rea do well on both? (I hope that we're still on topic)

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I stated earlier that I made a major change to my cornering technique in search of better results. And so, yes I've tried both ways. My best results have been going in with some gas on, quickly get to max lean and rolling on the throttle through the apex and then getting to WOT as I pass apex and get to the exit with my eyes on the next entry point.

 

How do you define "best results"? How do you know? What was the circumstance? Were you keeping lap times?

 

We've already been over the different types of corners and which ones you would want to be on the gas for. Please understand that I am speaking from the goal of racing, or the fastest and most stable and controlled technique when riding at the edge through corners that you must slow down for and turn sharply into.

 

It's pretty obvious that being off the gas increases steering angle, but that's due to parasitic forces, not just "being off the gas", true?

 

I'm not sure which parasitic forces you are speaking of, but, in any case, my reply is no. It is not just "due to parasitic forces". The dynamic state of deceleration alters weight distribution.

 

Compare ideal vehicle to real-world and I think you'll agree.

 

I'm not certain what you are asking me to agree with. But, what difference does it really make if I agree or not? Please understand, I don't need to scrutinize "beliefs" or "theories". I've already done all the "experiments" and am intimately familiar with all the scenarios in the "real world". I have thousands of racing miles, decades of data and mountains of scientific evidence to rely on. But I do wish you all the success on your own journey.

 

Cheers.

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May I humbly ask dear Sirs, is the technique the same for a rider on a 2008 CBR1000RR versus a 2003 SV650? How about an RS125? On the superbike you want to get it turned, pointed, stood up and on the gas, right? 125: Cornerspeed. Where do they differ?

 

Why does a rider like Sofuouglu do well on a supersport machine and not so on a superbike? Why does someone like Jonny Rea do well on both? (I hope that we're still on topic)

 

JB,

 

Doesn't change when I ride those bikes. In cases like this (this thread) wish we had a track and some bikes!

 

I think the question on the other riders is good, but also correct for another thread, want to post one?

 

CF

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When I watch racing on TV, I like seeing the telemmetry data onscreen almost as much as hearing the engines as the riders go through the corner. Seems to me that they're keeping some gas on.

 

As has been said, there are undoubtedly some corners where they are. But, the basic formula for a "sharp" corner that requires significant velocity change to negotiate does not.

 

May I humbly ask dear Sirs, is the technique the same for a rider on a 2008 CBR1000RR versus a 2003 SV650? How about an RS125? On the superbike you want to get it turned, pointed, stood up and on the gas, right? 125: Cornerspeed. Where do they differ?

 

A superbike or motoGP or even a 600 have more power to put down, hence, benefit from getting the turning done quickly and lift up to utilize that power to overcome the corner speed deficiency due to a longer wheel base and more mass.

 

A 125 is shorter and lighter, hence, in the hands of a skilled rider, can corner faster outright. Also, it does not have as much power to put down and must rely on maintaining corner speed to get a good drive out.

 

Why does a rider like Sofuouglu do well on a supersport machine and not so on a superbike? Why does someone like Jonny Rea do well on both? (I hope that we're still on topic)

 

Different strokes for different folks. Some riders can naturally adapt. Some riders have better technicians to adapt a bike to their style. Some don't.

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Hey Jay,

 

OK, I think I see where you were going before vis a vis, parasitic forces. Yes, it is mostly friction due to gravity that causes deceleration when you close the throttle. And, why the forks compress. But, the weight distribution also allows you to apply more turning force.

 

Yes, there is a theoretical point of diminishing returns if you apply too much weight or turning force, but, the traction of modern racing tires is pretty much beyond that unless you are trailbraking or the track is slippery. I have never flicked a bike away with too much weight on the front end except in slippery conditions or with cold tires.

 

Bottom line is that you can not turn in as hard or fast if you are on the gas, even at low speeds, because there won't be enough weight on the front end. And the geometry won't be as tight. You will run wider than if the forks were compressed.

 

That said, according to Cobie/Keith, turning up your idle, which is essentially the same thing as having the gas on a very little bit, can be helpful. But, I think that has more to do with the transition from off throttle to on throttle than maintaining speed during turn in. I don't have a copy of Soft Science so I don't know what Keith has said about it. But, I think it would be very difficult to consistently accomplish that trick by hand in any case. And the issue of having enough weight on the front end to turn hard and fast and sharp remains.

 

 

PS - I switched to two strokes GP bikes before I ever heard of raising your idle speed. GP bikes have no idle circuit, eg. they don't idle. So, I guess there is a scenario in this milieu I am not familiar with.

 

racer

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If you begin the turn in at....say 60mph off-throttle versus 60mph on throttle, why would it make any difference in the turning arc? After this turn is executed, who would be able to got the WOT sooner?

 

We see guys running wide at turn entry all the time (really) and then they pay for it in the middle or the end, so, yeah, think it does make a difference and you don't have to be doing even 60. But, try it, see what you notice.

I have some near closed, relatively safe corners by my house that I was just playing around with, and have to say that not being on some kind of throttle (not under acceleration) is pretty unsettling. That's when I was running wide, and was scared to get on the throttle in the corner. I'm going to try it while I'm warming up my tires (slow couple of first laps) in a couple of weeks after working on it on these corners. They're nowhere near as fast as on the track, but freaky none-the-less.

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Hey Cobie… I just came off LV 2day and can’t belive I found this topic because it is something that had me really perplexed on track. It was the second day, track reversed, and after settling into the change found that as the day went on the turns that were giving me a lot of trouble were the two sweepers after the straight…I found I wasn’t really going off the gas going into these…I asked my coach and he said you needed to come off the gas to initiate the turn…I tried and found it not good…it seemed I was stopping the bike in the middle of run…very un-natural…and it got worse as I tried to figure out WHERE to do it…so I just stopped trying and took those two turns with some throttle at the beginning then good on as usual and it seemed to work…good entry smooth roll on and exit…even when I followed my coach I found I was doing this and had no trouble keeping his pace… (PLEASE DON”T TELL MY COACH THIS :) ) so…here is my question You said that having the throttle on (we are talking constant throttle here) will make you run wide..and yes it would.. But what if you set up your turn to allow for the speed=throttle coming in…then you lean angle is set..your exit is set right…and in theory you go thru the turn faster…so long as the turn is soft enough that initiating the SMALL steering input doesn’t unsettle the bike/ I don’t know…maybe I just wasn’t going fast enough for those turns…I guess someone not being a newbie would just come into the turn much faster…then off throttle turn and roll on…maybe that is the solution…I don’t know…

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NY Dude,

 

Those corners begin with a fast decreasing radius (kinda long at the beginning), and then leads into another decresing radius. The fast guys were braking most of the way through the first turn, maybe cracking it on a little at the end (for sure not rolling) for the 2nd turn. Too much throttle, run wide going into the short straight, no?

 

CF

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NY Dude,

 

Those corners begin with a fast decreasing radius (kinda long at the beginning), and then leads into another decresing radius. The fast guys were braking most of the way through the first turn, maybe cracking it on a little at the end (for sure not rolling) for the 2nd turn. Too much throttle, run wide going into the short straight, no?

 

CF

There may be some confusion in this discussion, Cobie. Jaybird and I aren't talking about accelerating through a corner, just putting on enough gas to maintain a speed. I never accelerate INTO a corner. That, I would agree, would probably require you to have nobbies on the bike.

 

And I LOVE braking deep into decreasing radius turns. Lots of passing opportunities.

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NY Dude,

 

Those corners begin with a fast decreasing radius (kinda long at the beginning), and then leads into another decresing radius. The fast guys were braking most of the way through the first turn, maybe cracking it on a little at the end (for sure not rolling) for the 2nd turn. Too much throttle, run wide going into the short straight, no?

 

CF

There may be some confusion in this discussion, Cobie. Jaybird and I aren't talking about accelerating through a corner, just putting on enough gas to maintain a speed. I never accelerate INTO a corner. That, I would agree, would probably require you to have nobbies on the bike.

 

And I LOVE braking deep into decreasing radius turns. Lots of passing opportunities.

 

Love to have you both at the track for a day. I hear what you boys are saying, but....like to see it in action and then do a comparison.

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Love to have you both at the track for a day. I hear what you boys are saying, but....like to see it in action and then do a comparison.

Indian Summer today. Just hope to get off work in time to catch some daylight. I rode to work today.

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  • 2 weeks later...

I have some near closed, relatively safe corners by my house that I was just playing around with, and have to say that not being on some kind of throttle (not under acceleration) is pretty unsettling. That's when I was running wide, and was scared to get on the throttle in the corner. I'm going to try it while I'm warming up my tires (slow couple of first laps) in a couple of weeks after working on it on these corners. They're nowhere near as fast as on the track, but freaky none-the-less.

 

Another point to consider here is bike setup, especially at a more intermediate pace. If the bike is set up to turn in really quickly (a little low in front, for example) it can feel unstable to turn in while totally off the gas. I like a quick steering bike, but I find myself keeping a maintenance throttle through slow or sharp turns (prior to, and through, the turn-in) when riding at a slower pace in sighting laps or on the street, because it makes the bike feel a lot less twitchy. My point is that if you are not used to going all the way off throttle for turns, or if you are at a relatively low entry speed, it probably WILL feel really weird at first . It could even cause you to run wide - consider this scenario, you try an off throttle turn-in at your accustomed (maintenance-throttle) turn point. Only this time, your bike turns in SUPER quick so you hit an earlier apex... now you are wider on exit than before. Yuck, your turn in felt scary, maybe you leaned farther than you expected, maybe you had to stand it up a little to miss the inside curb. Yup, that felt lousy. But, with a higher entry speed it might have worked beautifully, becuase it is harder to turn the bike at a higher speed, so you get that same maintenance throttle arc but with a faster entry, therefore ultilmately a faster exit, does that make sense?

 

For me, being completely off throttle didn't totally makes sense until I reached a pace where the bike was stable for a quick turn AND I was going fast enough that it was difficult to turn the bike, so I really needed to be off throttle to get it turned to make my apex.

 

Racer's point helps clarify it for me, too - (hope I am paraphrasing you properly, dude) he mentioned that at race pace, for a sharp turn, you would normally be on the BRAKES prior to the turn, so you would definitely be off throttle (and possibly trailing brakes) right up until your turn point.

 

Certainly a series of turns that are progressively faster would be a different situation, you might be on throttle a little or a lot through the whole thing - if you have an 'easy' turn in, so you don't NEED to get off the gas for a quick turn, you wouldn't, right?

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Another point to consider here is bike setup, especially at a more intermediate pace.

Now that makes perfect sense. So, I guess we were all right (LOL). Thanks for stepping in and clearing that up.

If the bike is set up to turn in really quickly (a little low in front, for example) it can feel unstable to turn in while totally off the gas. I like a quick steering bike, but I find myself keeping a maintenance throttle through slow or sharp turns (prior to, and through, the turn-in) when riding at a slower pace in sighting laps or on the street, because it makes the bike feel a lot less twitchy. My point is that if you are not used to going all the way off throttle for turns, or if you are at a relatively low entry speed, it probably WILL feel really weird at first . It could even cause you to run wide - consider this scenario, you try an off throttle turn-in at your accustomed (maintenance-throttle) turn point. Only this time, your bike turns in SUPER quick so you hit an earlier apex... now you are wider on exit than before. Yuck, your turn in felt scary, maybe you leaned farther than you expected, maybe you had to stand it up a little to miss the inside curb. Yup, that felt lousy. But, with a higher entry speed it might have worked beautifully, becuase it is harder to turn the bike at a higher speed, so you get that same maintenance throttle arc but with a faster entry, therefore ultilmately a faster exit, does that make sense?

 

For me, being completely off throttle didn't totally makes sense until I reached a pace where the bike was stable for a quick turn AND I was going fast enough that it was difficult to turn the bike, so I really needed to be off throttle to get it turned to make my apex.

 

Racer's point helps clarify it for me, too - (hope I am paraphrasing you properly, dude) he mentioned that at race pace, for a sharp turn, you would normally be on the BRAKES prior to the turn, so you would definitely be off throttle (and possibly trailing brakes) right up until your turn point.

 

Certainly a series of turns that are progressively faster would be a different situation, you might be on throttle a little or a lot through the whole thing - if you have an 'easy' turn in, so you don't NEED to get off the gas for a quick turn, you wouldn't, right?

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I have just finished the level 3 at Sears Pt on 11-11-08. Lucky enough to have Cobie as my riding coach since I enjoyed his writings at "Cornering". Although I prepared with reading Keith's TTW,TTW2, SoftScience many many times before coming to the school, (that was after reading Andy Ibbott's motoGp manual, Nick Ienatsch's sport riding technique etc.etc ), due to lack of track practice, I still forgot to apply the throttle rule 1 (level 1 material) which Cobie noticed when I run wide at turns. He helped me to work on achieving a good entry speed (much higher than my own comfortable level) , throttle off, quick lean, with maintenance throttle then throttle rule 1. It really made the difference. I used to struggle in 3rd or 4th gear at turn 4 and 9. The "throttle off" with its smaller rake angle really allows quick turn with higher entry speed. Few laps later I was even able to try 5th gear at turn 4. (5th gear may not be good for exit acceleration but I just wanted a taste of entering that corner with higher speed, by the increasing confidence). So glad that turn 4 and 9 were not a big problem as before.

I found it was very helpful to be refreshed by Cobie and Racer's writings on this topic.

By the way, I need to thank Cobie for the smooth clutchless downshift technique too, my other bonus when returning to CSS.

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For me, being completely off throttle didn't totally makes sense until I reached a pace where the bike was stable for a quick turn AND I was going fast enough that it was difficult to turn the bike, so I really needed to be off throttle to get it turned to make my apex.

 

Racer's point helps clarify it for me, too - (hope I am paraphrasing you properly, dude) he mentioned that at race pace, for a sharp turn, you would normally be on the BRAKES prior to the turn, so you would definitely be off throttle (and possibly trailing brakes) right up until your turn point.

 

Certainly a series of turns that are progressively faster would be a different situation, you might be on throttle a little or a lot through the whole thing - if you have an 'easy' turn in, so you don't NEED to get off the gas for a quick turn, you wouldn't, right?

 

Sounds good to me, dude.

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Wow I just got back from Spain and am amazed when I found this topic on its 4th page in such a short time, that must be a record! How can there be so much of a debate regarding the basics of what we all practice and discuss.

When I joined this forum less than a year ago I talked about a lowside crash I had and how I couldn't understand how it happened, Cobie back then told me to study the sections on throttle control, I read those sections over and over and practiced them on the road and it has become the way I ride now, when I did my level 1 my instructor encouraged me to speed up my quick turn, this was a tough barrier to get over as I thought that I was turning quite quickly but now, wow, it still sometimes overwhelms my senses when I push the bars and reach my desired lean angle, there is a section in the TOTW books that asks you to rate yourself from 1- 10 at how quickly you can turn a bike 1 being slowest 10 being fastest, back then I rated myself as a 4, I am now probably really a 4 maybe a 5 and this is an off gas firm push on the bars that I would not even attempt if I was on the gas! In a perfect situation I will end my braking right at my turn point and to quote one of my favourite statements in the book, turn and burn!

 

Hay racer I recall a different thread where you offered someone $20 to buy the TOTW book, maybe you should keep the money to buy soft science lol, only joking, its an interesting read though!

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