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wantsasmart

Under Steer / Over Steer and tires...

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Brad, understeer is usually easier to feel and correct than oversteer. On a short wheelbase like the smart there is no time to react if the rear end slides out and the car starts to spin (if the ESP can't correct it). Many like to go to wider tires for comfort and looks, the difference in ride quality is amazing. The wider fronts have the biggest impact. To keep the built-in understeer, the rear tire size is also made wider. Our CDIs front "skinnies" 145/65, stock rear 175/55 and 195/50 are all very close in diameter, they really only differ in width. The wider tires do worsen your mileage due to more rolling resistance, as more rubber in in contact with the pavement. The effect is neglible unless your into hypermiling. The joy from being able to drink a coffee instaed of wearing it while driving, priceless.now to continue the off topic portion of todays programValgardForkbeard, Currently my winter tires are Ved 175/195s on roadster steelies. I'll let you know how they work out. As Fasteddy says "These are for the very low budget with a compromise of performance look and all weather driving without having quality alloy rims ". My pure and pocktbook deserve nothing less :biglaugh: . My summers are the original 175/55 B340s on roadster fronts, and Kumho KU21s all season tires (the cheapest 195s I could find, and with a UTQG rating of 420 should last quite a whlie) on the original rear steelies. They may not look pretty but they seem nicely balanced. My bravado gives up before the tires. Some will say it is foolish to go wide in winters, but a few years back I ran Yoko A008 195/50s all round on a Dodge Omni through 2 winters, never had a problem. My driving style is suited to my area. My tire choices are based on the expected conditions, and the type of driving I'll be doing. Also, unlike most people I have to park on my grass, the wider tire helps keep the ruts from getting too deep.please excuse me rambling on

Are the VEDs all-seasons or winters?

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Are the VEDs all-seasons or winters?

Wondering if he means Vredesteins? The Quatrac2 all-season is what I have. They're amazing.Bil :sun:

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Vredestein quatrac 2,all season M&S. Deep lug pattern looks like its suits my needs for MUD and snow. Winter thaws are my biggest problem.

post-2693-1195420000.jpg

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Brad - I'm not concerned with your lack of knowledge of vehicles, but I am concerned about your lack of knowledge as a licensed driver !!

Under- and over-steer are situations created when the driver makes an inappropriate driving input, such as too much throttle or too much steering for the vehicles' tires to transmit to the road surface. Certainly, car manufacturers design suspension geometries and make tire selections that bias each design towards being either inclined to understeer (most front-engine, FWD cars), over-steer (most high-powered, RWD cars), or neutral.

But it is the driver who has screwed-up when a car goes into over- or understeer; the driver has caused the vehicle to exceed the grip available from the tires, and the tires are now sliding sideways across the road-surface, instead of rolling along smoothly.

Learning what this feels like is easily accomplished by taking a Skid Control course, and once you understand what causes theses conditions (and what you - as the driver in control - have to do to correct the skid / slide), you will be a much better driver.

I have run some of the California canyons, and what startled me was the inconsistency of the grip available... sand blows up onto the road, and some corners (the clean ones) were great... but the next two could have sand on top, and the car would react to this lack of traction by under- or over-steering (depending upon what car I was in).[/i]

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Feel free to correct me if I'm wrong. I hear people say understeering is better than oversteering.Actually isnt oversteering better? cause that means your car can actually enter the corner faster than the current speed. Also oversteering is easier to control since u just turn less with the steering wheel. As to if you understeer, you have to feather the throttle to adust ur speed to correct your line. BTW, I find the car actually oversteers more than understeer cause I find everytime I enter a corner I can actually be quicker. And no I'm not scared to turn fast and I'm fairly good with my cornering line since I have experience with motorcycles on race tracks & countless twisties.

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I prefer understeering to oversteering; oversteering is pretty scarry. With understeer you can just brake and it ends. lolMy dad took one of those driving courses, I should ask him where he did it, it sounded like a lot of fun from what he told me! I think he did it in the hulking great 1990 Volvo 240 wagon as well.-Iain

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Inexperienced or sedate drivers find understeer easier to cope with than oversteer. That's why virtually all car manufacturers engineer significant understeer into their cars, and the cars that are capable of power slides (if RWD) almost invariably have traction control, which is driver-selectable. the theory is: driver gets scared when slip angles become excessive, driver backs off, problem solved. That's fine in normal driving, but in an emergency I prefer not to have the front end wash out on me. The clip of the (non-ESP equipped) smart versus the Lotus from Top Gear shows what happens with massive understeer and it's not pretty! One with ESP should be better.Keener drivers revel in oversteer, provided it is not in the "1970 Porsche 911 snap like a pit bull";) type oversteer. My 405 has very gentle lift-off oversteer, which is gloriously controllable, which allowed beautifully smooth, neutral progress at high speed on snow covered and gravel roads. Well...... when I used to live in an area with snow, that is ;)

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I prefer understeering to oversteering; oversteering is pretty scarry. With understeer you can just brake and it ends. lol

My dad took one of those driving courses, I should ask him where he did it, it sounded like a lot of fun from what he told me! I think he did it in the hulking great 1990 Volvo 240 wagon as well.

-Iain

Not really, cause hitting the brakes during a turn is actually unsafe (espeically during slippery conditions). You should be slightly accelerating during a turn and wide open throttle near the exit to straighten the car.

Thats why I think oversteering is better in the sense that you can throttle harder during a turn.

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Inexperienced or sedate drivers find understeer easier to cope with than oversteer.

Wow, subtle.-Iain

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Feel free to correct me if I'm wrong. I hear people say understeering is better than oversteering.Actually isnt oversteering better? cause that means your car can actually enter the corner faster than the current speed. Also oversteering is easier to control since u just turn less with the steering wheel. As to if you understeer, you have to feather the throttle to adust ur speed to correct your line. BTW, I find the car actually oversteers more than understeer cause I find everytime I enter a corner I can actually be quicker. And no I'm not scared to turn fast and I'm fairly good with my cornering line since I have experience with motorcycles on race tracks & countless twisties.

Actually it means your car can TRY to enter the corner faster than the current speed, but won't necessarily make it around. Oversteer means you may make it around, but you may come out of the corner backwards.

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The general rule for driving quickly is "slow in, fast out" - when it comes to corners.A very few totally gifted individuals (such as Prof. M. Schumacher) can demonstrate "fast-in, faster-out" techniques, but drivers of this calibre are very rare... and we ordinary folks should not try to emulate them.To be the best that you can be (as an ordinary mortal), try this technique...Do all your braking for the corner while going in a straight line. When you reach the turn-in point for the corner, release the brake pedal, and move your right foot back to the gas pedal. Balance the throttle (neither increasing, nor decreasing) your speed as you complete the first half of the corner. Once you reach the apex (mid-point) of the corner, you can gently increase your speed as you unwind the steering wheel, and once the steering wheel is pointed straight ahead, you can mash the gas pedal. Slow-in, Fast-out, as suggested.Properly executed, this technique has a huge advantage: when you release the brake-pedal at the turn-in point, your vehicle will still be in a 'nose-down' attitude, which puts extra weight onto the front tires. If you turn the steering wheel at that moment, you will benefit from the extra 'bite' the front tires have from the weight displacement, which therefore means the car 'bites' into the turn much better.No, they don't teach this at Young Drivers of Canada.But they should. It works.:drive:

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Nice description, Malcom... +1 cousin. Once one has driven that way for a few decades, it's the only natural way to address a corner ;)B:sun:

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Once you reach the apex (mid-point) of the corner, you can gently increase your speed as you unwind the steering wheel, and once the steering wheel is pointed straight ahead, you can mash the gas pedal. :

Malcolm,your probably the person to ask about this. After fitting roadster steelies on back with 195s, the car has a tendency to try to go tighter into the turn when accelerating. Some effort has to be applied to straigten it out and avoid the centre islands. I've only really noticed it on left turns. Could this be caused by the larger offset of the rear rims? or am I just accelerating too early in the turn?

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The general rule for driving quickly is "slow in, fast out" - when it comes to corners.:drive:

Sorry, small sidetrack.I am also a licenced racer here in Ontario! (Canadian Touring Car Series) I know of one Malcolm that races here as well. Do you usually race something with a bow tie on the nose?

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My experience in previous cars... Understeer = sliding out into the ditch in the middle of a corner (yay front wheel drive sentra!)Oversteer = Well managed "drift" resulting in some entertainment(80% of winter driving corners in my Camaro Z28 my pre-smart car).DDR

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I have decided after playing around that I much prefer oversteer to understeer. I don't know what I was thinking before.And yeah I always brake before the turn, then immideately let up on the brake when entering the turn, making sure I'm in the right gear and BAM power right through it! Feels frickin' awesome....Not as good as kneedraging, though. ;)-Iain

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