[ghostrider]

So those of you who've read some of my previous posts will know that I've just had the shoes on my brand new Swift diesel upgraded to 15" rims riding Yoko A-drive 195/60 R15 rubber. I was enjoying them - they looked good, they soaked up the bumps, they were quiet, and they handled well. Not as well as the 195/50 R15 S-drives on my Ikon, but they were good nevertheless.

Till two nights ago.

I was coming back home at 2am in the morning on LJ road (which is a divided 2+2 lane arterial road in the city), and my phone rang. I took my eyes of the road for about three seconds to see who was calling. Big mistake. I know, I know. I shouldn't have done it, but anyway...
I look up, and there's a taxi driving on the wrong side of the road!!! He's heading straight for me, with no lights on. Instinct kicked in, and I slammed on the brakes. At that point, I must have been about 75 feet away, doing no more than 45 or 50 kph.

And the tyres locked up completely.

Now my Swift doesn't have ABS, and I was in 4th gear. Thank god I had the presence of mind to take my foot of the brakes and swerve hard left, and then time came to a complete standstill. I must have missed the cab by a couple of millimetres. If there had been someone on my left, I would have collected him broadside when I swerved left.

So...

How on Earth do Yoko A-drives lock up on a level road at 50kph??? I pulled over to the side of the road ready to beat the cabdriver to within an inch of his life, but he was long gone. I walked over to the spot where I had locked up, expecting to find dirt or loose gravel on the road, but there was nothing. It was completely clean. The tyres locked up on a clean road with no loose debris!!!

This can't be normal, can it?? I know that cars with no ABS have a greater propensity to lock up under hard braking, but at 50kph in a new car whose brakes have only done 1500 km??? I can understand brakes locking up, but not at such a low speed. And the tyres provided no stopping assistance AT ALL. Is it the lack of ABS, or the tyres, or both??

[ashthedivx]

Yoko lockup at 50kph ?? It something new for me.. I have been recently upgraded to 195/65 R14 with Yoko A drive and i found it pretty easy to drive. I have been driving at 60-70-80 easily and didn't found any such breaking issue so far. Though haven't been on highway so far till now but in-city driving they seems to be perfect !!

[ghostrider]

Me too. I've been on a few 90+ runs with this car on the Western Express Highway, and it braked just fine when needed. But my point is under emergency braking, everything locked up at 50kph, and the A-drives skidded merrily along the road.

This sucks, because now I have to drive knowing that if I'm ever in an emergency braking situation, things are going to go to hell in a handbasket very quickly!!

Originally Posted by ashthedivx

Yoko lockup at 50kph ?? It something new for me.. I have been recently upgraded to 195/65 R14 with Yoko A drive and i found it pretty easy to drive. I have been driving at 60-70-80 easily and didn't found any such breaking issue so far. Though haven't been on highway so far till now but in-city driving they seems to be perfect !!

[Jaggu]

panic breaking at 40 with no ABS can happen, I have experienced in many cars, please note that swift brakes have real food grab.

[ghostrider]

Food grab? What's food grab?? You've lost me there...

Originally Posted by Jaggu

panic breaking at 40 with no ABS can happen, I have experienced in many cars, please note that swift brakes have real food grab.

[Jaggu]

LOL that was a typo! Good grab!

[ghostrider]

Well, that makes perfect sense.

But seriously, most of the car's I've driven here in India have been non-ABS. And the way the Swift locked up with the A-drives in that situation is disconcerting, to say the least.

Still trying to understand... is it the brakes, or the tyres?

Originally Posted by Jaggu

LOL that was a typo! Good grab!

[iraghava]

GR - Most tyres would lock up even at 50 kmph if you're doing panic braking. It's not the tyre's fault but rather the driver's. Reason is that you're applying more force on the brakes than is required & as a reason they're going beyond the adhesion limits of the tyres.

[Vid6639]

Are you pressing the clutch imemdiately? Generally with whatever tyres you have the tyres will lock up.

I've got the Ptenza G-III and the michelin's energy XM1's to lock up at 40km/hr. Idea is to downshift as well to prevent the lock up and modulate the brakes. That's the only way out in a non-ABS car.

[ghostrider]

Vid, Ishan,

Nope. No clutching. Even in an emergency braking situation, I usually have the presence of mind to use the clutch only when the car's starting to stall, or if I have time to downshift into a lower gear. Modulating the brakes is a great concept in an ideal world, but I think nine times out of ten either you're not going to have the time to do so, or you're not going to remember to do so.

Thanks for your inputs. I'm inclined to believe that any tyres would lock up, and there's nothing wrong with the Yokos, as such. Especially if you're having the same issues with the XM1s.

Originally Posted by vid6639

Are you pressing the clutch imemdiately? Generally with whatever tyres you have the tyres will lock up.
I've got the Ptenza G-III and the michelin's energy XM1's to lock up at 40km/hr. Idea is to downshift as well to prevent the lock up and modulate the brakes. That's the only way out in a non-ABS car.

Originally Posted by iraghava

GR - Most tyres would lock up even at 50 kmph if you're doing panic braking. It's not the tyre's fault but rather the driver's. Reason is that you're applying more force on the brakes than is required & as a reason they're going beyond the adhesion limits of the tyres.

[nitrous]

Originally Posted by viddy

Idea is to downshift as well to prevent the lock up and modulate the brakes.

Who can do that when panic braking? Maybe Lewis Hamilton. :

The last time my tyres locked up when braking, my reflex made me take my foot off the brakes. Modulating is tough in my experience because of the forward G-forces.

[Shan2nu]

Who can do that when panic braking? Maybe Lewis Hamilton.

If he could he wouldn't have hit Kimi in Canada. They don't call it "panic" for nothin. LOL

Shan2nu

[ghostrider]

Somehow I doubt Hamilton can do that. All he seems to be able to do is lock up his brakes every other corner, crash into his rivals in the pitlane, and then force them off the track in the run up to the first corner on lap 1.

Originally Posted by Shan2nu

If he could he wouldn't have hit Kimi in Canada. They don't call it "panic" for nothin. LOL

Shan2nu

[Rehaan]

As Ishaan said, ANY tyre (available today) would lock up.

In a case like this, a grippier tyre would lock up a fraction of a second later than a less grippy tyre (and hence also help retardation a bit more), but it still would lock up - assuming that your car's braking system was good enough (which it really should be).

Originally Posted by ghostrider

...Modulating the brakes is a great concept in an ideal world, but I think nine times out of ten either you're not going to have the time to do so, or you're not going to remember to do so...

Absolutely agree, and thats one of the reasons why they have ABS!


However, to state the obvious (and important) - dont forget that if you had looked up 2 seconds earlier or avoided looking at your cellphone - this could have been avoided all-together

cya
R

[ghostrider]

Originally Posted by Rehaan

However, to state the obvious (and important) - dont forget that if you had looked up 2 seconds earlier or avoided looking at your cellphone - this could have been avoided all-together
cya
R

Totally with you on that last point. However, I think the idiot cabbie driving on the wrong side of a divided road with no lights on whatsoever had a minor role to play in the whole incident as well.