When I panic-braked and the engine quit in gear, I slid, but the engine was off, no rotation was taking place. New to EKN? Clutch use on shifter kart?
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Any and all input is appreciated. David Cole Keymaster. July 3, at pm You should upgrade or use an alternative browser. Shifter Kart Clutch? Thread starter crappyballer Start date Aug 26, Status Not open for further replies. Messages 92 Reaction score 0 Location Messages 48 Reaction score 0 Location Vermont. Your welcome. I think what jmorey92 meant is sometimes on homemade type shifter karts, guys use a ratcheting type shift lever kinda like a shifter a standard transmission car would have and then they mount a motorcycle type clutch lever right to the shifter itself so you'd operate both the clutch and shifter with the same hand.
Messages Reaction score 0. For downshifts, you do not need to blip. Having said that, I always did when I raced them. It was kind of a 'method' thing. You just do the same thing on the downshift that you do on the upshift only backwards.
Again, you're just trying to reduce the pressure of the driveline holding the dog ring and dog together. The fastest guys driving shifter karts that I know national champion level never blipped on downshifts. They made their downshifts very fast and very late.
The 'shock' to the driveline is very small because of next to no rotational inertia of a kart engine and the fact that they would make the downshifts so late.
Posted 23 October - Very interesting answers, thank you guys, you just helped me to kill this doubt, because when driving Formula Vee and vintage touring cars in my country, I found a very pleasant thing to do the heel toe technique, but these cars are equipped with a H pattern gearbox and you have more "space" between the gears to do the heel toe. Having said that, I found a little nonsense have to blip the throttle in a shifter kart, because in my mind it "cancels" the advantage of a sequencial gearbox..
Another doubt: in NASCAR races in road courses, I noticed that drivers who brake with left foot always blip the throttle, while drivers who brake with the right foot always do the normal heel toe technique.. My question is, if you try to drive these cars with left foot breaking, but whitout blipping the throttle in the downshifts, you will not be able to downshift or you will breake the gearbox?
Is not better to do the normal heel toe technique than have the "advantage" of left foot braking but having to "wait" the time to blip while you find the neutral between the gears? If you were doing qualifying-style downshifts the gearbox wouldn't last long.
Nor would the brakes. So at race pace they have plenty of time to do deliberate downchanges. But you have to blip. Otherwise those things will lock the rear and it's not something you can just flick into a corner and survive.
But just how did you briefly disconnect the engine from the wheels to allow the "blip" - clutch or some other method? I know what you mean by "method" and "memory" - I literally don't like to even think about left foot braking, or driving on the "wrong" side of the road that is; the right hand side or changing gear with my right hand.
I'm going to guess that you need to understand how a racing gearbox sequential or H-pattern. The people mentioning sychromesh gears are off base. So first, investigate the design a bit on your own.
Now here's how it works in practice. For a downshift. Put some pressure a couple pounds on lever in the downshift direction. The gearbox has some pressure on the dogs-dog ring interface which is holding it in gear. As you blip, increase the pressure on the lever. At some point as the engine responds to the blip it will release the pressure on the dog faces and the gearbox will be allowed to shift into the next lower gear.
It's the reverse on the upshift side. Put pressure on the lever. Lift to reduce the pressure on the gears. Once you lift the gear lever will be allowed to move and you shift the gear. The throttle lift and reapplication should again be as quick as possible. It's a small but completely usable window. The gear selector forks and dog rings travel through these windows between every shift. If a box gets stuck between gears for any reason, it's refered to as 'being in a false neutral'.
The only 'real' neutral in a sequential box is either between 1st and second or between first and reverse. This has to do with how the barrel 'star' detents machined and the designers choice. Posted 24 October - But are you saying this because all the peculiarities of the Cup cars? Because look the example of this BTCC video, the driver is downshifting without the clutch and without blipping as I have to do in my shifter kart?
So why in a Cup car you will lock the rear if downshift whitout blipping or heel toe and in this BTCC car not? So the answer to my question is that you can find a "neutral" between gears in a sequential gearbox. Cup cars are extremely sensitive to downshifts. For one thing the gearboxes that they use are not the cleanest shifting things. They've gotten much, much better over the years, but you aren't going to mistake it for an Xtrac.
Second, the rear suspension of a Cup car is very prone to wheelhop while braking. Once you get the thing hopping around you basically can't turn the steering wheel because the rear end has very little grip.
Making very smooth often clutched downshifts helps this. I've known guys that if they had a big brake zone that goes from 6th gear to first on a bumpy street course will clutch on the downshifts to avoid wheelhop. That was in a formula car with a sequential box. A lot of BTCC cars are front wheel drive too. And the car in that video is a sequential shifter.
Posted 25 October - Posted 26 October - Shifter karts are probably much more sensitive to locking the rear tires during a downshift than a Cup Car is. Shifter karts have no suspension to speak of, so they tend to lose grip and slide very easily with abrupt changes in torque applied to the rear tires.
Yeah but a kart that isn't locking the rear under braking isn't being driven hard enough. Posted 28 October - It's not even close, a kart is not hard to deal with at all.
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