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38

It depends on the specific vehicle. Many modern standard transmission cars in the US have a clutch pedal sensor that will not allow you to start the vehicle if the pedal isn't fully depressed. You'll turn the key and nothing will happen. I've had older vehicles that preceded this sensor that could move the vehicle if the clutch was engaged and the ...


26

The lower the gear, the better the job the engine compression will do at holding the car if the brake fails, that's because a lower gear makes the engine spin faster and requires it to do more work for the car to move. So 1st is better than 2nd, between reverse and 1st it's not so obvious – but from the examples people are finding it looks like 1st is a bit ...


25

Being from Canada, I feel compelled to mention that if you do not depress the clutch while starting when it is at all cold out (let's say < 0 Celsius) you will notice the starter motor labouring significantly as it spins both the cold engine and the cold transmission. If it is really cold, your battery may not have enough power to start the car at all in ...


19

When I'm on a hill with the front of my car facing up the hill I park the car in first and turn the wheels away from the curb so the transmission is fighting against gravity. When I'm on a hill with the front of my car facing down the hill I park the car in reverse and turn the wheels into the curb so again the transmission is fighting against gravity. ...


15

Reverse is pretty equivalent to first gear, for a ratio of around 3.2ish. If it were any lower, it would be difficult to get started from a stop since the torque just won't be there. If you've ever driven a stick-shift, try starting from a stop in 2nd or 3rd gear and you'll see what I mean. For example - ratios for my manual 5-speed 2007 Mazda6: 1st: 3....


13

The answer is no because you mention being limited by your redline. Regardless of power, a certain RPM will result in a certain speed for a given gearing. Chances are the gear ratios were chosen based on the factory output of the engine. However, for other cars this may not be the case. Because of wind resistance (in many cases) a vehicle may not have ...


12

Every window has what's called a window regulator (here's a representative image): The window itself attaches to the window track. This keeps it steady and level while moving up and down. As you can see, there are gears at the bottom which connect to a motor (or a crank if a manual), which prevent the whole assembly from going down all at once. This is why ...


12

So, looking at a couple common manual transmission gear ratio charts, first gear would be best. Why? It has the highest ratio. Although it is (in the charts I found) very close to reverse. Here's a chart for Honda Civics (up to '91 I think) Here's a PDF from Toyota's press room with their Corolla specs. Highest ratio = greatest amount of torque applied to ...


11

As DucatiKiller notes, coasting downhill in neutral is usually considered unsafe, as it increases the chances of overheating your brakes. It is also illegal in many jurisdictions. Questions about driving techniques are generally off topic here, but you do have a question about how engines work that I think is (maybe marginally) appropriate: why do you get ...


11

Great question! There are several basic differences. Here is my main article that I am pulling from. Firstly, straight-cut gears produce less side-to-side torque, allowing the engine to deliver much more torque through them. Here's an image that illustrates the side-to-side torque of helical gears: As the gears move around, they also push apart from ...


11

Summarized Answer No, HP does not determine MPH in a gear, the gear ratio does. Although there are hypothetical ways that HP can seem to make the vehicle go faster in the same gear, it doesn't actually change the speed capacity of that gear as long as the engine RPM is limited. Expanded Answer As noted, the answer is no... or at least not really. In ...


10

Should be no problem at all. The manual is being overly cautious, since the usual case for shifting from neutral into drive is when you're stopped hold the brake will prevent the car from starting to move until you release the brake. But when you're already moving there is no need to hold the brake.


10

No harm done On contemporary vehicles there is no direct mechanical linkage between the gear selector and the automatic transmission. Instead, the gear selector selects a "state" (e.g. N, D, R, 1, 2...) which is relayed electronically to the transmission controller and acted upon if the circumstances are deemed favorable.


10

As you say you change gear from 3rd to 4th, this means you have changed the gear ratio between the engine and the wheels causing a different engine rpm.


9

How could you possibly know that the helmet had never been dropped from the moment of its manufacture until it came into your possession? Even once you do own it, can you really be sure it's never been dropped while you weren't looking? I guess what I mean to say is that if it's not safe to use a helmet after it's been dropped, there's a good chance ...


9

I'm assuming you have a manual transmission. Stop doing that, you will damage your transmission. Your powertrain can be broke down into three sections. The engine, including the fly wheels. The clutch and input to the transmission. Finally the transmission output. When you push the clutch the engine is disconnected from the transmission input. When you ...


8

It depends on how you do the skipping If, when you do it, you hear loud clunks, that means you are not matching the RPM's to the road speed, to the transmission. Motorcycles have a synchronous transmission with with relatively fragile shift forks operated by a shift drum. The forks move the gears side to side to engage. if you are hearing a loud 'clack' ...


8

My theory is that the engine would be forced to rotate the other way around, wouldn't it? Then, because of that, the engine would stop, and therefore it will "generate" a lot of force to the transmission and cause the car to reduce speed (all of this, if nothing breaks, of course) Put simply, in most cases, the motor will stall and the tires will lock. In ...


8

First gear when pointing down hill, reverse when pointing up. If your car ends up rolling, the engine will turn in the correct direction. If you park in reverse pointed downhill and your car rolls the engine will turn backward, and vice versa. This can cause various problem with the engine including skipping a tooth or binding on the timing chain/belt and ...


8

Well the simple answer is (as you suspect)... No. With fixed gearing, you are going to be doing the exact same speed at any given engine RPM with 100bhp or 600bhp.


7

As far as I know rental companies have insurance that covers this sort of thing. This may be a good time to contact a lawyer. You can't break a gearbox by doing the wrong thing in traffic. You would destroy the clutch first. The only ways to destroy a gearbox is by running it without oil (not your responsibility because it's a rental) or popping the clutch ...


7

I'm assuming no one here answering has driven a Subaru manual transmission before or long enough. I'm fairly certain there is nothing wrong with your synchros or transmission. Subaru's are generally very hard to shift into first while in motion. I daily-drive a 2011 WRX and and the first gear has always been like that, even when it was brand new. I have ...


7

Look at it this way, the sequence is indeed linear - 1-2-3-4 and so on, with the neutral sitting in-between 1st and 2nd gear. Which means, to shift to neutral from 1st gear (or down from second), one has to gently nudge the shifter into neutral, else it would directly jump to 2nd gear. This is desire-able as one generally doesn't need to shift to neutral ...


7

Chilljeet has a good answer, but it's also partially a safety thing. When you're slowing down to a stop, you're clicking down in the gears until you can't click down anymore. If the bottom gear was neutral, you're a sitting duck until you can get back in gear if someone is coming up behind you at a high speed. You need to be in gear and able to react ...


7

There are three considerations when making a low end/small capacity engine Cost Reliability Space available 2 and 3 directly affect 1. To make a gearbox more reliable you need to make the parts more durable, this is normally achieved by using more materials or more robust materials which add to the cost. To make a 6 speed gearbox fit in the same space ...


7

How is a 0-100 run done? The fewest number of gears possible will be used, because that's the fastest way to get to a given speed. Engines typically put out their highest power in a certain band of RPMs, so you will accelerate as much as you can in first gear (to the red-line, or to a certain RPM where you know the power starts to decrease), then shift to ...


7

Electric vehicles can "engine" brake by using the drive motors as generators. As they generate electricity they consume the car's potential energy - either from speed or elevation or both. The energy can be used to recharge the battery or dissipated as heat. The changeover between power and regenerative (dynamic) braking is usually handled automatically. So ...


7

It doesn't "have to be done in second gear". It just usually works easier to do it there. The reason is simply as you put it, that being it isn't trying to spin the engine as fast in 2nd gear as it would be in 1st. If the engine is a little harder to start, you won't be wasting all of the momentum trying to get 1st gear to kick over. In 2nd gear, the ...


7

Engaging gear increases the effort needed to move the car Typically (assuming a RWD vehicle): In neutral: car moves when wheels, axles, diff(s), propshaft & gearbox output shaft turn In gear: car moves when wheels, axles, diff(s) propshaft, gearbox output shaft, gearbox input shaft, flywheel, clutch plate, pressure plate, crankshaft, valvetrain, ...


6

The "Don't drop your helmet" warning that comes with the helmet is pretty scary, but from the seat to the ground is a pretty short drop. If you were not riding on the freeway at the time, then it is unlikely you damaged the helmet. In "Motorcycle Accident Cause Factors and Identification of Countermeasures: Technical report (1981)", Harry Hurt thoroughly ...


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