Hi Paul, of course. I believe that’s how you get your Mondi into a “perpendicular to the road slide, and bring it back around with precision , every time.” Feel free to let me know if I have that wrong.
Banked turn, the more gravity pulls on the car, more friction on the tires, THE KART IS PINNED TO THE ASPHALT ALMOST SO THE STEERING BECOMES STIFFER , you dont know crap , and by the way, anytime you want to try and race with me , Im always at Adams, I will walk away from you, oh, I will walk away from you on two as well !!! I have plenty of track experience as well. Im walking away from all the experienced Kart guys out at Adams, until I run out of stamina . Your pics dont mean squat, come on out here with your best machine, and we can have a go on any canyon road, or track that you want , bring that Toni Kart as well . Like I said, the flat turns at Adams are a lot easier to steer the wheel than the banked turns are. National champ 20 years ago doesnt mean anything to me . In these pics, by the time we all made it around the carousel on 74 ,I passed both these cats, and Im not in even in full leathers and on a machine with moto x bars , no clip ons . Thank you
By the way, many years back, before I bought my 328 , I was racing at Willow Springs , streets of willow, or maybe it was the Kart track, they had a huge Ferrari day there, there was this rich prick from Texas driving his X Schumi Formula One car around big Willow, he was a joke, its that simple. Just because somebody is in their F40 driving around some track, doesnt mean squat. It takes a lot of money to race / drive full size race cars on a track, thats why I bought a Kart, Im not rich, with that being said, Karting is way more difficult to master, like someone on here said, shifters are the closest one can get to being in a Formula One car, and now I see why , its insane to say the least , and you get worked like crazy, its that simple. Senna said it himself, " it was true racing " . Tomorrow Im back on track , my Kart has new tires and new gearing, Im going to try and see what kind of times I can click off , no matter what, I will be having a blast, highs will be in the high 60s and low 70 s !! Woo Hoo !! Thank you
Let's see if we can figure this out. An unbanked curve has a max speed determined by the friction available to the make/model/condition of tires on the vehicle. When negotiating a curve, at constant speed, most of the grip available to the tire patches are going to create centripetal acceleration to make the turn. When there is a banked curve, the max speed increases because centripetal acceleration is created by the x-component of the normal vector (N vector composed of Nx and Ny, the horizontal and vertical vectors) that you get for "free" because of the bank (Nx = N sin theta, Ny = N cos theta, where theta is the bank angle). Without the bank, a driver/rider has to turn the steering wheels into the curve and off the straight line in order to create Nx. https://study.com/academy/lesson/circular-motion-around-a-banked-circular-track.html So traversing an unbanked curve can only be done by allocating the available grip budget to centripetal acceleration, Nx. The cost of traversing a banked curve depends on the speed at which the curve is traversed. The formula for the optimal speed at which to traverse a bank of a particular angle is given by: v = sqrt (gR tan theta) where g is the gravitational constant, R is the radius of the curve, and theta is the bank angle. For a 20 degree banked curve with a 100 meter radius, v = 42 mph. What this means is that if you traverse the banked curve at 42 mph, you get the necessary centripetal acceleration just by virtue of the bank angle. There is no steering input necessary, so you are not using up any of the "grip budget" available from the tires (so long as you don't add an additional component of acceleration or deceleration). You will follow the curve naturally at the radius R. If you go faster than 42 mph, you'll have to add steering input to reduce the radius (because the physics wants the vehicle to be at a larger radius), while if you go slower than 42 mph, you'll have to add steering input to turn away from the center (because the physics wants the vehicle to be at a smaller radius) to stay on that line (desired radius). This is when you start consuming the "grip budget" and start introducing factors which will eventually limit the speed you can take the curve. So for an unbanked curve, you don't get any turns without consuming some or all of your "grip budget", while for a banked curve, you get a substantial amount of turning without ever touching the "grip budget" (again assuming no other acceleration/deceleration vectors). So it can't be disputed that a banked curve lets you go much faster than an unbanked curve. In fact, it may be that the 0 degree curve may not even be traversible at the speeds that are optimal for the higher bank angles. Now, the next thing to look at is what happens when you go faster than the optimal speed for a given bank angle. In this case, you start off with the optimal speed and then you have to look at the available grip from the tires of the vehicle as well as the radius of the curve and the velocity. Just as with a 0 degree curve, you start using up the available grip to adust the centripetal acceleration to the desired amount to stay at a certain radius (the desired line). At some point the grip runs out and the tires slide. Let's say that's 50-60 mph for a 0 degree curve. But because the banked curve starts off at 42 mph for free, it can go much higher, say 70-100 mph, before it runs out of grip. So the banked curves are adding significantly to the speed. The important point here is that the velocity is much higher. While the Ny component is determined solely by the weight of the vehicle (Ny = mg, where m is mass and g is the gravitational constant), the Nx component is partly determined by the velocity of the vehicle (Nx = mv^2/R, where m is mass, v is velocity, and R is the radius); where the Nx component increases as the square of the velocity. So if you're going twice as fast, than Nx might be four times as great. Since N increases if Nx increases, that might very well create a psycho-physical perception of the vehicle requiring more turn in force (after reduction through the steering ratio) on a banked curve than without a bank. However, that's because the situations are not really comparable. You can't go as fast on a 0 degree curve as a banked curve, and the increase in Nx (which is a component of N, the normal force) is a necessary corollary to the substantially increased speeds in the turns on a banked curve. Note that it isn't "gravity" that's increasing; Ny never changes, it's always mg. It's Nx, the centripetal acceleration, that's increasing; and you can't get the higher speeds in a banked curve without a larger Nx.
Hi Yin, Given two curves, one banked and on zero degrees, at the same given N, the banked curve requires less steering effort. The Nx and Ny are outputs of the N but I was referring to one given velocity (N) on two separate turns, one flat and one banked, All else being equal (ha!) the banked turn requires less steering effort than the flat turn. As you correctly pointed out, you get a certain amount of turn through the curve for “free” on a banked curve: “What this means is that if you traverse the banked curve at 42 mph, you get the necessary centripetal acceleration just by virtue of the bank angle” with no steering input needed. That was my point with that.
What Sherpa and Yin fail to account for is the color. None of those apply if the kart is structural blue.
Yes. Your comparison is correct because you're referencing the same value of N between the two scenarios. I went on further to explain why the other argument was meaningless. That is he was comparing scenarios with substantially different values of N (which also means substantially different velocities). Complaining about the difference in forces felt due to the higher velocities on a bank vs the slower velocities without the bank is like complaining that wind resistance goes up as you go faster. So what? That's the price to be paid for going faster.
Yin, Thanks for the detailed exegesis. Re-reading the posts, I believe the root claim is the torque required to turn the wheel is higher on a bank. I don't think speed is in question. All joking aside, I really don't know. I just have a history with @sherpa23 where I've come to guess his experience is valid. Assuming everything else equal (speed, track, vehicle, tires, etc) is more torque required to turn the steering wheel on a bank or not? (both left or right, as in up the bank or down, not sure if it makes a difference) Go Caltech!
I'm not an automative engineer and all I'm doing is reconstructing Physics 1 problem solving to address the question that came up. If I made any errors, feel free to bring them up, but I was hoping that would help to end this sidetrack more quickly in respect to the OP's original purpose in creating this thread (how hard is it to do a fast steering rack mod yourself) . The answer to your question though would be that for the same speed (which requires that the speed under discussion be one that the vehicle could traverse both of the banked and unbanked curves without losing grip), then the steering force required in the banked curve should be much less than the unbanked curve. Further, even at speeds that the unbanked curve can't support, the steering force required shouldn't ever be more than the maximum generated on the unbanked curve to first order. The argument for this is that the steering force felt at the limit is determined by the capabilities of the tires and the size of the tire patches. Since the weight, tires and steering ratio haven't changed, a vehicle should lose grip at approximately the same amount of steering force felt in either case. But that will be at a much higher speed on the banked curve. However, to second order, that might not be the case. For example, if the vehicle is generating significant downforce at higher speeds (adding to the "weight"), then I would think you could see a greater steering force than the maximum steering force on an unbanked (slower speed) curve. Other factors, such as the weight distribution, suspension system, and road surface (flat, domed, dished, condition) might also affect which tires lose grip differently under the two scenarios, which could change the maximum steering force felt before the first tire loses grip in each scenario. There could also be some psycho-physical effects such as the grip on the handlebars or steering wheel changing under the two conditions (because of changing the lever arm along the handlebars or leaning in more and changing the lever angle of his arms), which might affect perception of steering force. That's why I worded my explanation the way I did. I try not to argue people out of their personal perceptions as there's usually no way that ends up anywhere useful.
ginoBBi512 Why? Cuz math. Thank you @ylshih You have and always have been a scholar and a gentlemen. Cheers
I think all you guys have missed something. I've only ever driven a rent-a-kart, but I noticed that it had incredible amounts of castor, which means that as you turn the wheel, it lifts the front up. On a banked curve, the faster you go, the more weight is on the kart, so it becomes harder to turn the wheel. The end. And FFS, don't spoil your argument with BS about recovering a 90 degree slide - your entire story becomes "tainted".
I'm sorry, I'm having a hard time following. If I understand correctly; having a car/kart set up in a way where it can do '3-wheel-motion' (as low riders say) would cause an opposite effect? @ylshih ? Close by requesting we don't spoil the argument by bringing up an unrealistic niche case? Regardless of whether your point is correct or not, (I really don't know) I couldn't help but laugh (and die a little inside.)
Everyone knows the true measure of racing happens at the Bonneville SaltFlats, which is straight so there’s that. Plus I just wanted to get in on this thread
I would not say that, all Bonneville is top speed runs, it has nothing to do with racing, its that simple. Real racing is WRC / Formula one. Motorcycle racing and Kart racing. Indy is a waste of time, same as Nascar . If that Patrick degenerate could have stayed were she was all those years, doing absolutely squat, almost anyone could. Oh I forgot about sprint cars on the dirt and Lemons / sport car racing. Thank you ,
