Braking with the gears what ridiculous practice

Inactive

Conor wrote: »

OH.MY.GOD. If you use the brakes on ice, you lock the wheels up. That means that there is NO BRAKING whatsoever.

Of course if you were driving at an appropriate speed for the prevailing conditions, that wouldn't happen.:rolleyes:

Inactive

Conor wrote: »

Actually, IAM and RoSPA do teach a lot that's different to the DSA because the BASIC DRIVING TEST doesn't include a lot of it. The BASIC DRIVING TEST is a test of a BASIC LEVEL OF COMPETENCY.

I am well aware of that, however nothing is any different.


You obviously speak from experience, have you ever taken anything other than basic driving tests then?

Obviously not.:rolleyes:

Inactive

Conor wrote: »

Actually, IAM and RoSPA do teach a lot that's different to the DSA because the BASIC DRIVING TEST doesn't include a lot of it. The BASIC DRIVING TEST is a test of a BASIC LEVEL OF COMPETENCY.

And in the HGV test, WHICH THE DSA CONDUCT, you are required to use your gears as well to slow. So again, you're wrong.

Stick to driving cars and having a 500% accident rate of that of HGVs because Cat B licence holders are so knowledgeable and competent. Stick to stopping solely using your brakes on snow and ice and sliding into the car in front but you'd better make sure you have protected NCB. I'll use my gears and stop before I hit them.

I actually have a HGV Class 1 licence as well as an IAM Certificate.

I have also attended the DSA Centre at Cardington, and Harmondsworth before that.

nullogik

I was taught to brake with the gearbox by a car driving instructor only two years back. I then changed instructors and was told by the new guy that it was unnecessary with modern cars and just to use the foot brake. Confusing...

Anyway I drive an auto now so it doesn't really matter.

LotusExige

I would suspect that the idea of useing the gears to slow the car down comes from two old facts. The first one is that once upon a time cars had mechanicly operated brakes and uneven brakeing would have probably been the rule more often than not. Probably not a big beal on a dry road but on ice or snow a bit too entertaining hence the idea of useing the gears to slow down in slippery conditions. However, these days with hydraulic brakes that would not apply. In fact as the brakeing by changeing down will only be via the driven wheels it will be very limited compared to the brakeing by use of the brakes.
The other one, useing a lower gear for a long descent has two reasons, one historical and one still valid. The historical one is that in the days of drum breaks the drum would expand more than the show as it heated up thus causeing the shoe to have to travel further to maintain contact with the drum. This would translate into the pedal gradually sinking further and further eventually running out of travel. That situation does not apply with disk brakes. The second is that as the brakes heat up the coefficient of friction will lower and more and more pedal pressure will be needed to give the same brakeing effect. In extreme cases the fluid can boil and really spoil your day.
The HGV is of course a totaly fifferent animal. It can weigh up to 44 tonnes as aginst 1 to 2 tonnes for a car so that each and every time he slows down he has to dissipate between 22 and 44 times as much energy as the car driver.

pault123

Idiophreak wrote: »

If you're decelerating from (say) 60 to a standstill, by the time you get to 20, a lot of people on here will still be in fifth, just about to stick the clutch down. If you were using your gears you'd be in 2nd or 3rd.

Now, who stands more chance of being able to stop? The one that's already in second, or the one in fifth that's going to have to have to change hastily into second (through neutral)?

Hold on I think i'm misssing something here? Why would the driver in 5th have to go into 2nd!!?? The driver in 5th who had slowed down to 20mph with engine braking would simply press the brake and put the clucth down as he pulls up to the lights. The brakes would stop the car.

Idiophreak

pault123 wrote: »

Hold on I think i'm misssing something here? Why would the driver in 5th have to go into 2nd!!?? The driver in 5th who had slowed down to 20mph with engine braking would simply press the brake and put the cluth down. The brakes would stop the car.

Not if the brakes had failed, which is what we were talking about...

tomstickland

In fact as the brakeing by changeing down will only be via the driven wheels it will be very limited compared to the brakeing by use of the brakes.

Yes, but in most cases you're only doing gentle braking anyway because you anticipate and start early.

pault123

Idiophreak wrote: »

If you're decelerating from (say) 60 to a standstill, by the time you get to 20, a lot of people on here will still be in fifth, just about to stick the clutch down. If you were using your gears you'd be in 2nd or 3rd.

Now, who stands more chance of being able to stop? The one that's already in second, or the one in fifth that's going to have to have to change hastily into second (through neutral)?

Idiophreak wrote: »

Not if the brakes had failed, which is what we were talking about...

If you read my message you quoted - I was saying surely you guys don't go through your gear box on every stop on the off chance your brakes might fail? That seems a bit paranoid to me! Its like saying i'll check my tyre pressure before EVERY journey and my oil and water incase something else goes wrong.

Conor_3

Inactive wrote: »

Of course if you were driving at an appropriate speed for the prevailing conditions, that wouldn't happen.:rolleyes:

So how would you come to a stop, by magic?