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Questions about driving a manual car?

  1. Dec 1, 2011 #1
    Hello everyone,

    I have never driven a manual car before and just drove one for like 10 minutes once and I have some questions because I don't know what's going on?

    1. In a manual car after you engage the clutch can you keep your left foot away from clutch and then only use right foot to break and accelerate like auto driving.

    2. To stop the car why do I have to press clutch and then the brake. What happens if I only press the brake? then I don't have to reengage car and it would be easier.

    3. Also why does the car stall or stop. Isn't this bad when it happens when you are driving. What should I do to restart if car stalls.

    4. Why do I have to press the clutch when changing gears?

    Thanks!!
     
  2. jcsd
  3. Dec 1, 2011 #2
  4. Dec 1, 2011 #3
    Sorry I didn't make myself clear but I really don't want to know too much about mechanics. I just want to know the driving aspect of manual cars. This the wrong forum, this should go in a forum like how to drive a manual car. But at the moment this is the only forum I'm registered in so I asked it here so that people who drive manual cars can tell me.
     
  5. Dec 1, 2011 #4

    Ranger Mike

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    1. In a manual car after you engage the clutch can you keep your left foot away from clutch and then only use right foot to break and accelerate like auto driving.

    Driving instructors recommend you use the right foot to Brake. The habit becomes second nature so same action when driving either manual or automatic transmission car..I have always used left foot to brake as most race car drivers do.



    2. To stop the car why do I have to press clutch and then the brake. What happens if I only press the brake? then I don't have to reengage car and it would be easier.

    If you do not put transmission in neutral or depress clutch the engine will stop.

    3. Also why does the car stall or stop. Isn't this bad when it happens when you are driving. What should I do to restart if car stalls.

    The car stops because the engine stalls. The engine stalls because the clutch connects the engine to the wheels. When the clutch is engaged you have a direct drive from engine to the wheels.

    4. Why do I have to press the clutch when changing gears?

    Clutch must be disengaged so that tension ob the drive gears is taken away and this permits you to change gears. When clutch is released by lifting your foot , tension is placed on gears by the rotating engine
     
  6. Dec 1, 2011 #5
    If you've only just started driving a manual, you've probably stalled.

    When the clutch is engaged, the wheels are connected to the engine, if you come to a stop the wheels stop rotating, so the engine must stop rotating too (ie a stall). By depressing the clutch, you are mechanically disconnecting the engine from the road wheels, allowing the engine to spin freely.

    When you stall, handbrake on (optional, but probably a good idea) gear into neutral, depress the clutch, and turn the ignition.

    Also when braking you should only depress the clutch at low RPM. By clutching in first you are freewheeling, all the braking work is being done by the brakes (you aren't being helped by engine braking).
    When just slowing down, you can brake without using the clutch.


    It's good practice, to take your foot off the clutch pedal when you know you won't need to be changing gear immedately. It stops you pressing the pedal slightly (partionally disengaging the clutch) and slipping the clutch.
     
  7. Dec 3, 2011 #6
    as mentioned, if you are new to driving a standard remain calm and enjoy the comedy.

    there are usually many stalls, jerking starts and jumps / stops.

    the mechanics of how a clutch works is the same in each car, but the key to driving any particular car is finesse as each car, the relationship between the clutch and accelorator will ussually be different. some clutches long, some really short. (in sports car for example)

    the only way to learn is to do it. once you learn on one car, it will take a couple times of taking off to get a different car smoothly rolling. w/o burning the clutch up.

    make sure radio is off and there are no distractions. go someplace like a LARGE parking lot and practice. feel the car and listen to the whine on the engine. if the engine is reving too high and the car isnt moving forward fast enough, more clutch, if the engine sounds like its clunking or dieing, more gas! one goes in the other out. once your rolling smothly, start to watch the RPMs and listen to teh engine, it will tell you when to shift. when will depend on how fast or slow youre going. once its time, push in the clutch, let off gas, fairly quickly and at the same time, shift then in on gas, out on clutch......again, listen to the car it will complain if done in correctly. if you smell the clutch, youre really doing it wrong.

    easy!
     
    Last edited: Dec 3, 2011
  8. Dec 3, 2011 #7

    Janus

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    1 2 and 3 are interrelated. As mentioned already, with a manual transmission, the engines are directly geared to the engine. This means that the RPM of the engine and the speed at which the the tires rotate have a fixed ratio for each gear.
    If you are in an upper gear, and slow the car down too much, or try to shift to a higher gear if the car is at too low a speed with out disengaging the transmission from the engine by pushing the clutch, the engine will be forced to an RPM that is too slow to keep it running and it will stall. The same is true if you try to stop the car while keeping it in first gear. If you try to stop the car, the direct linkage to the engine also prevents the engine from turning ( automatic transmissions use a torque converter which automatically does the job of the clutch for you). By depressing the clutch, you are disengaging the engine from the wheels, allowing it to run while you are stopped.
    This allows the gears to sync up properly. When you change gears, you are changing the engine RPM to wheel speed ratio, If you don't disengage the engine from transmission you will have gears moving at different speed trying to mesh up and they will grind. There is a method of shifting without clutching but it involves popping the car out of gear and then using the accelerator to match the engine RPM to the new gear ratio for the speed you are going and then putting it into the new gear. This however is a very tricky maneuver, and not something that the typical driver does or should do.
     
  9. Dec 5, 2011 #8
    You really SHOULD know about the mechanics, as it will help you understand what you are doing and why, and will ultimately help you drive better. Even my girlfriend understood this when learning manual...she requested for a diagram of what the hell is going on when she presses the clutch, stalls, etc.

    This goes with everything in life. If you want to be good at anything...cooking, running, flying, filming, photographing, love-making, talking, drinking, etc... you need to understand WHY you are doing things, and the inner mechanics of what is going on. Don't just blindly follow a cookie cutter recipe.
     
  10. Dec 6, 2011 #9
    Thanks for all the replies :smile:
     
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