|
AutoX, DE and Racing Discussions All discussions related autoxing, DE, amateur and professional racing activities |
|
Thread Tools | Search this Thread | Display Modes |
|
#1
|
||||
|
||||
Re: How To Brake?
It is pretty amazing to see this level of action this close to the ground. Setting up a kart is really complex I think, although I have NO experience with it, but without any springs/shocks, it is all geometry and probably millimeters of adjustments.
__________________
Fatih Selekler 997.2 GT3 Last edited by FTS; 06-27-2011 at 10:53 PM. Reason: a big incomplete sentence meaning the opposite of what I meant :) |
#2
|
||||
|
||||
Re: How To Brake?
Quote:
If you watch the video closely you'll see that on the back straight I peak over 90 mph (92 to be exact) according to the GPS, and take most turns about 70mph. Some people would say that karts don't have to slow down much for turns, but the inverse is true too- since everyone is trying to slow down the least (because we all want to win) it's a dogfight. To put it into perspective, laptimes in my situp class should be around 1.38.xx at Mid Ohio. That's a kart with a water cooled 125cc two stroke, no gearbox, disc brakes in the front and rear. Sit up Shifters are about 7 seconds faster, laydown shifters even more so. There's no ABS, no traction control, no power steering. If we have Tillotson carbs we can tune the needles on the fly, if it's a Keihin/Mikuni/d'Ellorto then we have to watch the weather station like a hawk and put the right jets/needles/tubes in. We check chassis alignment three or four times a day, and change alignment/setup throughout the day to keep up with the track conditions. Brake bias is adjustable on the fly- however, i don't know too many people who use it unless there's something quite a bit wrong. Karts are rear biased- rear locks up before fronts, because the rear tires are bigger (bigger contact patch), weight is rear biased, and the fronts are useless if they lock up first (neither brake nor directional control). Because the bias is rearward, you learn to really carry speed through the turns- threshold braking while turning marginalizes the brake AND turning ability, probably either sending you off spinning or over slowing the turn- basically , if you can threshold brake into the turn you're not going fast enough. At least, that's how it works in karts. In cars it's a different story because there are a lot of engineered aids- brake bias is computer controlled... ABS, TC and SC intervene with most "optimistic" input... Steering rack ratios are overly slow requiring a lot of input... And engines are so tractable that you are rarely out of the power band (unless you're really goofing up) which covers up a lot of mistakes. Basically, modern cars are much easier to drive fast on tracks than cars from even as recent as 10 years ago. |
|
|