Stupid questions people ask you when stopped

Discussion in 'The Perfect Line and Other Riding Myths' started by cold_fire, Apr 13, 2009.

  1. helion42

    helion42 Been here awhile

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    I've heard of this, and it makes sense although it would be more effective to just turn off the engine if you're going to be waiting longer than 30 sec.
    More electrical draw = more alternator output to compensate battery and increased resistance = more drag on the engine thru alt. belt = increase in consumption. Of course it's pretty small differences, but when you pinch every penny I guess it adds up.
  2. slide

    slide A nation in despair

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    I am not sure that in those days, with those ancient engines fueled by those carburetor devices, that turning the engine off for a minute's stop would save fuel. Perhaps we have an expert on antique engines here who can answer factually.
  3. scottrnelson

    scottrnelson Team Orange

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    If you can start the engine without pressing the gas pedal down, which should be the case when it's hot, it doesn't use any extra fuel at all to restart an engine. On all but CV carburetors (usually only on foreign cars, like the 240-Z) if you pressed the gas pedal down the accelerator pump squirted more fuel into the carburetor. Normally when the engine was cold, you would press the gas two or three times which would both squirt more fuel into the intake and set the automatic choke, then you would start the car. This would be the case for American-made cars from the 50's and 60's.

    So if it could be restarted without pressing the gas pedal down at all, even 20 seconds would save fuel.

    Modern fuel injected engines would be even better, because they don't squirt in any extra fuel.
  4. bwalsh

    bwalsh UUU, UUU!!!

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    Never heard the "to save gas" explanation but I have heard of people in here in the States who think that using the headlights unnecessarily is bad and will kill the battery...like there is no charging system. :loco

    Where do they get these people? :lol3
  5. Nadgett

    Nadgett Been here awhile

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    Just the other day I... oh, never mind.
  6. Vertical C

    Vertical C Long timer

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    At lights wouldnt it be running off the battery not the alternator? The revs would be too low.

    Like everything there is merit, but it might be insignificant.
  7. atomicalex

    atomicalex silly aluminum boxes

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    An innocent colleague who is painfully American, on the phone....

    IC: are you going to bring your bike back when you come home?
    Me: I hope so. Have to check with NHTSA on that.
    IC: Why, is it like right hand drive or something?
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  8. Kannonball8

    Kannonball8 Adventurer

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    On turning off headlights or shutting off engine at stop lights. I have no idea what the savings would be to shut off the headlights but I really think it would be almost too small to measure - lighting load = 2 x 55w headlights + 2 x 20w taillights = 150w or about 1/5 hp tops (750 watts / HP) for 30 or 40 seconds. But the shutting down the engine thing is what bugs me, maybe you can save a small amount of fuel, but, what about wear on the starter and battery? I start my car in the morning and drive 12 miles to work, I have the possibility of getting stopped at 4 traffic lights during my drive. This could give me a total of 5 starts each way or 10 per day instead of 2 per day. If I only use the vehicle to go to work and I work 240 days per year, I'm starting the vehicle 2160 extra times a year. You can't tell me I'm going to save enough gas to cover the starters and batteries (and maybe ignition switches) I'll use up. (or am I completely wrong?)
    Bruce
  9. slide

    slide A nation in despair

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    Those accelerator pumps didn't have temp sensors to shut them down?

    Sure, today it makes great sense to shut off if you have a hybrid to start on the electric motor and then the engine kicks in right off such as the Prius does. Presumably, after about 30 seconds, the energy it takes to regain battery charge is less than the fuel spent idling. I'd guess some engineers have figured this out long ago which is why, to my knowing, all hybrids do this.
  10. hoadie72

    hoadie72 Adventurer

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    Those tiny savings across an hour or two's commute per day per week per year add up to considerbale savings.
    As for additional load on your battery and starter - if your engine is warm and is maintained there is insignificant wear and load on your battery.

    You're obviously not aware that most car manufacturers these days have cars who's engines automatically stop and restart in traffic. These engines are fitted to more or less regular petrol and diesel cars (ie not just hybrids). It helps give them the edge with fuel economony and while I haven't tried it, reviews I've read have said that it works flawlessly - well in premium brands anyway.
  11. scottrnelson

    scottrnelson Team Orange

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    It sounds like you have no idea what an accelerator pump is.

    It was something inside the carburetor that squirted extra fuel into the intakes every time you opened the throttle. It was there to make up for the air being able to speed up more quickly than the fuel and helped keep the air/fuel mixture more correct. Usually it was either a plunger (think of a syringe) or a rubber diaphragm. It was 100% mechanical, so no temperature sensors involved. As far as I know, the ONLY temperature sensor of any sort used in American engines in the 50's and 60's was the cooling system thermostat that regulated how much water went to the radiator.
  12. Tip Over

    Tip Over Whoopsie!

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    Those cars that have the auto shut-off, that are not hybrids, have huge heavy duty starters. Hybrids don't use their starter motor unless their battery pack is drained. It's all the electric motor's doing (pretty trick stuff).


    On a normal car, even when warm, if you are constantly starting and stopping it, you will wear that starter motor out much faster then normal.
  13. DAKEZ

    DAKEZ Long timer

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    ** than **
    :1drink
  14. Thanantos

    Thanantos Ride hard.

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    You rang?
  15. Tip Over

    Tip Over Whoopsie!

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    [​IMG]

    :deal:lol3
  16. hoadie72

    hoadie72 Adventurer

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    Let's put this in perspective. A typical family might start and stop their car engine 20 times over a weekend and god knows how many times during the week. That starter motor will last 20+ years. So starting and stopping it during a few times during a commute isn't going to make a lot of difference.
  17. eepeqez

    eepeqez Long timer

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    The average trip length for urban vehicles is something like 10km/6miles; the average traffic light interval is probably more like 0.5km/0.3miles. Restarting at every second traffic light instead of just once per trip has the potential to reduce the life of starter motors and ring gears by a factor of ten, bringing your hypothetical 20 year starter life back to just 2 years.

    Automated engine off and restart at stops in traffic lights has only become viable with larger batteries and starters.
  18. Chromer

    Chromer Not going gentle

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    Mazda has a system for their direct-injection engines that doesn't require using the starter motor at all. The engine is stopped with a piston just past TDC ready for the power stroke. To restart, fuel is injected and sparked. Off you go.

    To be fair, idling a modern 4-banger for an hour uses a ridiculously small amount of fuel. You'd have a bigger benefit from reducing aero drag by slapping on an underbody tray or finding a way to take 100lbs out somewhere.
  19. RidingDonkeys

    RidingDonkeys Purveyor of Awesome

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    Remember when we used to talk about stupid questions people ask you when stopped? Those were the days.
  20. Tip Over

    Tip Over Whoopsie!

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    "Hey, I heard goldwings have air conditioning, so why are you complaining about how hot it is"?


    Yeah. 96 degrees. Stuck in traffic, and my phone crashed because of the heat, leaving me with no music.

    Also, I was almost late for school.