Can you lock your wheels at 70mph?
Can you lock your wheels at 70mph?
Author
Discussion

Welshbeef

Original Poster:

49,633 posts

228 months

Wednesday 14th November 2012
quotequote all
New thread to avoid OT on he 1.25ltr fiesta doing 28mpg thread.

I don't mean the secondary brake (handbrake) but the foot brake emergency stop can you lock the wheels at 70 mph or is it during deceleration ad if so roughly what speed?
I cannot lock mine at that speed and from memory don't think they lock until down to 20mph ish?

carreauchompeur

18,322 posts

234 months

Wednesday 14th November 2012
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rofl

eldar

25,287 posts

226 months

Wednesday 14th November 2012
quotequote all
Welshbeef said:
New thread to avoid OT on he 1.25ltr fiesta doing 28mpg thread.

I don't mean the secondary brake (handbrake) but the foot brake emergency stop can you lock the wheels at 70 mph or is it during deceleration ad if so roughly what speed?
I cannot lock mine at that speed and from memory don't think they lock until down to 20mph ish?
ABS?

_Batty_

12,268 posts

280 months

Wednesday 14th November 2012
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What was the tipple tonight fella? Gin?

Welshbeef

Original Poster:

49,633 posts

228 months

Wednesday 14th November 2012
quotequote all
eldar said:
ABS?
You can feel that kicking in through the pedal.

C. Grimsley

1,381 posts

225 months

Wednesday 14th November 2012
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If a car is not equipped with abs it will lock at any speed.

Carl

Bohally

943 posts

177 months

Wednesday 14th November 2012
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Pub lunch was it? wink

340600

608 posts

173 months

Wednesday 14th November 2012
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Try putting it in 1st gear.

Chrisw666

22,655 posts

229 months

Wednesday 14th November 2012
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Welshbeef, how do you lock the wheels of your ABS equipped 330d?


911p

2,361 posts

210 months

Wednesday 14th November 2012
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Depends on the weight of the car, tyre grip, road conditions, power of the brakes, loads of factors.

The GT3 is happy locking its wheels at over 100mph in the dry, but the Golf would never be able to do that. Likewise, the same car with very grippy tyres might not lock its wheels at high speeds, but put some st tyres on and it would happily lock up.

The question is a little unclear, but whether or not a car will lock its wheels at a given speed depends on a lot of factors, it's not a generic thing.

C. Grimsley said:
If a car is not equipped with abs it will lock at any speed.

Carl
Not true. The faster a car goes, the harder you will need to press the pedal to lock the wheels - you can get to a point where the wheels won't lock.

ETA - by 'lock', I mean tyres pushed past their limit of adhesion, which would obviously cause ABS to kick in on a car equipped with it.

Edited by 911p on Wednesday 14th November 20:22

Big Fat Fatty

3,315 posts

186 months

Wednesday 14th November 2012
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340600 said:
Try putting it in 1st gear.
Or reverse. hehe

maxdb

1,547 posts

187 months

Wednesday 14th November 2012
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Yes you can lock your wheels at 70mph wink

58warren

589 posts

209 months

Wednesday 14th November 2012
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Try it on ice at 70 mph and let us know how you get on...

FastNReliable

308 posts

209 months

Wednesday 14th November 2012
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340600 said:
Try putting it in 1st gear.
Yes, 1st gear will lock the wheels at 70mph.

And possibly the engine too..


squeezebm

2,319 posts

235 months

Wednesday 14th November 2012
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WTF

surely this clown should get at least a yellow for the continuous bks thread starting or is ph that desperate to keep the google rankings ffs

Gooly

977 posts

178 months

Wednesday 14th November 2012
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Edit, quote not showing, but in reply to your post in the last thread;

Well I have. And as for the F1 comparison, I'm pretty sure thats bks, but if it isnt then thats probably more to do with the fact that F1 cars run high grade racing slicks as opposed to half worn kumho ecstas, or to do with the amount of brake line pressure.

If you really want to check me up on it you can go look at the skidmarks just before one of the cameras on the north circular dual carraigeway.

Also, usually cars with ABS cant lock their wheels, hence why your BMW doesnt do it. Thats usually the point of ABS.

Edited by Gooly on Wednesday 14th November 20:26

Contigo

3,139 posts

239 months

Wednesday 14th November 2012
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Where do these threads come from? I think Welshbeef has been on a session again today, too many shandies at lunch and then decides to wonder if Anti-Lock Brakes actually lock!

Mr E

23,066 posts

289 months

Wednesday 14th November 2012
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Unless the car has serious aero (and therefore weight changes with speed), or somehow your coefficient of friction changes with velocity; it will lock wheels at the same pedal pressure regardless of speed.

vit4

3,507 posts

200 months

Wednesday 14th November 2012
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Done it at ~55-60 mph. On the A13, near the A406 roundabout. Merc CLK on the slip road to A406 up ahead slows down pretty sharply. Brain donor then goes to swerve onto the A13 in front of the car in front of me over the hatchings at about 20 mph, has second thoughts and stops half into the lane yikes. The Insignia in front of me did a fairly uneventful-looking but very bloody rapid emergency stop whereas I screeched up in a mildly impressive cloud of smoke. No ABS and completely missed the threshold grumpy. Definitely glad of the 'two-second' rule that day.

Eighteeteewhy

7,259 posts

198 months