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19

tl;dr: We do. It's just expensive. One of the differences between electric and chemical energy motors is that the electric systems make it much more convenient to capture and retain energy (e.g., a battery). All you need to do is use induction to create an electric current right there at the wheel while braking. Point that current at that battery and you've ...


14

tl;dr: No. This sort of vehicle dynamics question best addressed by Racing Car Vehicle Dynamics What follows is a basic discussion at the high school physics level. As you will see from the reference text, high school physics is insufficient to statically model the complete vehicle system. A dynamic model is required to agree with easily obtainable ...


13

why using your clutch during braking can be considered unsafe I have ridden motorcycles for years. Engine braking is a component of safe riding. The engine itself can be ok and not receive any damage from pulling in the clutch while breaking other than it is additional wear on throw out bearing for the pressure plate within the clutch. The throwout ...


9

Although automated manuals are becoming more popular, the 2012 Civic (from my 2 seconds of searching) appears to be a normal automatic. Even still, I'm guessing your vehicle may have the sensors and programming necessary to determine that it's descending an incline and is employing engine braking to help you slow down. What it sounds like it's doing is ...


9

Think of it this way. If you need to brake so incredibly hard that you're worried the automatic transmission is getting in the way, you're better off worrying about things besides whether or not you're in neutral. You're probably about to crash or lose control, so train yourself to concentrate on steering, or making sure you're arms are out of the way of ...


9

In answer to the question "What is regenerative braking and why don't we use it?", we do. With normal braking, forward momentum of the car is scrubbed off by the brakes by turning them into heat in the brake disc with subsequently dissipates and is lost. With regenerative braking, instead of the movement of the car being lost to the atmosphere as heat, it ...


8

The information & links posted by Paulster2 offer excellent explanation of what the various types of brake fluid are. There are a few grade : DOT3 DOT4 DOT5 DOT5.1 The difference between them is a specificed standard regarding the boiling temperature, which rises as the DOT number rises, and amount of water absorption. There are based on two ...


7

I found this description of synthetic based brake fluids. According to the page, all brake fluids are technically "synthetic" in that they are man made and do not contain a petroleum base. "Synthetic" brake fluid, as we think of it, has a silicon base. Non-synthetic brake fluid (normal brake fluid) is glycol based. There are trade offs to each type. Silicon ...


7

The only reason it feels more natural to you is because that is the way you do it. It was beat into me from Driver's Education never use your left foot to brake. To me it feels natural to not brake with my left foot. There is a great article I just read about using your left foot to brake from a driving instructor. In the article he basically says things I ...


7

Regenerative braking is a system that stores the energy that instead would be lost to heat in the brakes. While these systems sound great they come with a whole host of their own problems. Before even getting into the energy storage and generation the actual service brakes become very complicated. For regenerative braking to work properly the brakes can't ...


7

The most common cause of intermittent brake failure is a faulty master cylinder. The master cylinder is similar to a bicycle pump. It moves brake fluid instead of air. Stepping on the brake pedal moves a rod that pushes brake fluid to the wheels. If a seal is failing it may allow brake fluid to seep by it reducing the fluid pressure to the wheels. As an ...


7

Basically, yes. Automatics don't have a clutch per se, but you're causing additional wear and tear on the internals. Basically you're reversing the power flow -- instead of the engine driving the wheels, you're driving the engine with the wheels. Obviously this occurs normally when you decelerate, but by downshifting you're increasing the amount of force ...


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 ...


6

I agree with MT_Head's and Donovan's answers, but I'd like to add that the downshift itself can be quite heavy on your synchromeshes if you don't do it right. When you up-shift, the input shaft drops in speed by ordinary friction, and the synchromeshes don't need to work much in order to match it to the speed of the output gear. However, when you down-shift,...


6

If you're coming to stop, the inertia of the vehicle drives the wheels. This keeps the engine spinning if you don't touch the clutch until the absolute last moment. In your case it sounds like this is 1300 rpm. Before you press the clutch, the ECU disables all fuel injection for this time period. This saves fuel. If you press the clutch early, the ECU must ...


6

Vibration through the steering wheel is generally caused by a defect in a rotating part or an imbalance in a rotating part. Note: neither pads nor shims rotate. If the problem is the same after you replaced the pads, I think that makes a pretty compelling case that it's not the pads/shims. Likely sources of this vibration are in order of likelihood: Warped ...


5

Just some anecdotal evidence. I downshift at least a few times a day. Only one gear at a time and never send my tach anywhere near the red, BUT I NEVER RIDE THE CLUTCH. Unless it is an emergency I'll downshift and come off the clutch almost as quickly as I do when I upshift, If I'm going to fast for this I don't downshift yet, UNLESS IT'S AN EMERGENCY. ...


5

If you double-clutch the downshifts and ensure that the engine is running at exactly the right speed before you engage the clutch, any additional wear will be insignificant. Double-clutching will, if done properly, eliminate any additional wear of the synchronizers and if the engine is running at just the right speed before you engage the clutch after the ...


5

Some answers correctly identified wear of synchronizers as a possible concern on manual transmission cars, but then they offered double-declutching as a solution. However, it is very hard to correctly judge the amount to press the gas pedal, making it very likely that you're either over-revving or under-revving the engine. Thus, there is some wear on the ...


5

Using up your clutch to slow down all the time? Replacing your clutch will cost you several hundred bucks, and unless you have a lot of special equipment, you won't be able to do it yourself. Any time you use your transmission for accelerating, you wear down the clutch, throwout bearing, gears, synchros, and bearings. If you use the transmission to slow ...


5

Your instructor properly objected because the clutch/engine and the brakes do opposite things: the former adds energy to the car (speeding it up) and the latter removes energy (slowing it down). If you use both at the same time, then you're just pumping energy from the engine into the brake pads, to no good end. If at the same time you're feathering the ...


5

The torque converter in a "standard" automatic transmission does the job of a clutch, and it doesn't really wear out in the same way as a clutch does - a clutch is two dry pieces of material holding each other through friction (kind of like 2 sheets of sandpaper pressed against each other), and each time the clutch is slipped those surfaces rub against each ...


5

Heel and Toe Pedals I think to truly heel-and-toe drive well, you need to have a setup similar to the one in the image. Something that's designed to do it proper. There's some that are super cheap. You have to consider how much it will effect your normal driving though. This setup will prevent you from trying to bend your leg all weird to actually do it. ...


5

You cannot. You can't even do it that well with GPS. The only relevant OBD2 parameters are speed and RPMs. If the wheels are locked or traction is otherwise lost, neither of these can be used in the calculation. Brake pedal position is also not a standard PID so you won't always even have a reference point. I am assuming you want to log data from within ...


5

It is because you have, over years, “educated” your left foot /brain / muscle memory to hit the pedal and go to the floor ie clutch to change gear. You now have to re-learn the use of the left foot to use the brake pedal - and yes it is possible but just takes practise... Similar is heel and toeing where one uses the right foot to operate brake and ...


4

Your brake system's balance can fall into several areas of concern: The calipers in and of themselves have sliders and pistons that can cause uneven pressure. sliders: I always remove, clean and grease the sliders first, be mindful that some vehicles actually have rubber on the sliders that will swell over time and cause lockup/drag... just replace the ...


4

Tires are going to be the biggest change you can implement. The widest, stickiest tires you can get for your conditions. Typically, any car can lock its tires up under normal conditions (average load, speeds). If it can do this, the braking system is more than adequate, and the tires are the first thing you should change. Now, when you start upgrading tires,...


4

If you have worn out steering parts, these can cause your issue, worn parts cause slack in the steering, when you brake it will pull to the side which has the most slack at the time. You can test for steering slack by starting the car, leave it park, set the brake and roll down the drivers window, get out and reach inside the window and rock the steering ...


4

What you are most likely experiencing is the pull from tires when breaking on uneven surface or road with grooves from heavy vehicles. If you have rather wide, sticky, square tires, this is what it would be. Notice how water stands in sort of lines, that's where the grooves are formed from vehicles. Depending on if you are closer to the right side of the ...


4

It's not a stupid question at all! You are right to be concerned, brakes are critical for safety and you need to deal with this before you get in an accident. The ABS light turning on while it was on the lift is probably a red herring, especially as it turned off once it was back on the ground. An ABS problem isn't likely to cause inconsistent braking, what ...


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