Tyres!

Stephen H · 2012-03-23T14:27:00+00:00

Hi all.I bought my current golf M4 Estate 2 litre turbodiesel privately two years ago.The car originally has steel wheels with 195/65 R15 91V tyres on it.The seller claimed that he found them "rubbish" under his ownership and put four 17 inch alloy wheels on it.The front tyres are Event WL905 255/45R17 94W's and the rears are Talon Triangle TR968 255/45 R17 90V. The spare tyre is a steel rim with a Continental Conti Eco Contact 195/65 R15 91V.According to the Golf manual, I can use any tyre between the rim diameter range of 16 to 17 inches and between 195 to 255mm wide and a aspect ratio of 45 to 65.I've now had the Golf two years and I find that they current tyres on the alloy rims are really rubbish as soon as the roads have the slightest bit of wetness on them. I find I get front wheelspin when I accelerate and also the back end slides outwards when I corner. So when there's a slightest bit of rain, I have to drive much more gingerly as if I am driving on Black ice. Thankfully there is no problems when I need to brake sharply.Now the tyres are up for replacement.I'd like the panel to advise what tyres will achieve that sweet spot of:Value for money tyresImproved fuel economyCan do high miles between replacement intervalsLong lasting in time (I do 6k miles a year so don't want rubber perishing before tyre has worn)Improved handling in rain for both accelerating and corneringObviously in achieving that sweet spot, I have the additional choice of:(a) stick with the alloy rims and get a set of four matching tyres(b) To go back to four steel rims and buy 4 Conti Eco Contacts so that I can then start using the spare in a 5 tyre rotation pattern?(c) Do (b) but replace the spare tyre as well so I have a matching set of 5 tyres to achieve that sweetspot?(d) use another wheel rim size to use specific tyres that hit the sweetspot?RegardsStephen.

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Gordon H 14 years ago

That can only be because everyone gives them a wide berth. ;-)

Ironically, a white van man (10 year old Transit) had an accident involving damage and injury in a store car park about 3/4 mile from where I live.

I received notification of intent to prosecute because the b*****d gave a false name, and my address and postcode, and also filled in a transfer of ownership to the false name at my address.

I had some "interesting" communications with police, a lawyer, and the DVLA before I could convince them I had never seen the vehicle.

A simple phone call satisfied the law firm, but the cops required a recorded delivery for the vehicle documents, even then still harassed me, and my daughter made a personal call at the station and gave them a piece of her tongue. That shut 'em up, but they obviously failed to take up my lead of "why don't you pursue the previous owner", because then the DVLA entered the scene with a threatened debt recovery action because I hadn't taxed or SORN ed the van or paid a fine!

That necessitated a Fax of my declaration and evidence, but all went quiet after that...

I have no doubt that some white van men are first class chaps!

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Yvan 14 years ago

Nedavno Mrcheerful napisa:

Testing was done from 100kph (~62mph ~28mps).

5th: Pirelli CINTURATO P7 --> Wet: 45.3m 42nd: Linglong L688 --> Wet: 60.5m

Someone will correct me if I am wrong:

a=(v1^2-v0^2)/2s=28^2/2*60.5~6.5m/s^2

v1=sqrt(vo^2-2as)=sqrt(28^2-2*6.5*45.3)~14mps ~50kph ~30mph

So while car with Pirelli tires is stationary, same car with Linglongs will still travel at 30mph.

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Mrcheerful 14 years ago

whic sounds plausible and a speed I don't want to hit anything at. Particularly not a person.

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Mrcheerful 14 years ago

I am very glad that has never happened to me, I hate grief like that. I once had the misfortune to mow down a pedestrian that walked straight off the pavement, she only suffered bruising, but I went and reported it and produced the documents at the nearest police station within a couple of hours of the collision. Two weeks later I got a recorded delivery letter threatening prosecution for failing to produce! Happily everything had been correctly written down, so quite why it happened I'll never know, but it made me feel quite physically sick at the time.

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Mrcheerful 14 years ago

ears sell pirelli at 58 quid in that size

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johannes 14 years ago

If the cars are nose to nose, then why use this measure instead of the perfectly understandable 10.5m. As I pointed out, 10.5m is NOT 3 small cars driving on the road! So your introduction of small city cars were irrelevant. Perhaps I am more familiar with the metric system than you are. But the length were give in metres in the first place.

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johannes 14 years ago

I do too as a habit, probably because of fear of missing the odd camera. But I feel that cars behind me don't like this and start tailgating; they expect me to go faster after passing the camera. But I don't...

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SteveH 14 years ago

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johannes 14 years ago

If you block the tyres, then friction is a constant negative force, so the negative acceleration (a) is constant, so the speed decays linearly in time.

v = v0 - at, stops at T= v0/a

s = [integral (v0 - at) from time 0 to time T ] = v0*T - aT^2/2

When substituting T = v0/a gives s = 1/2 v0^2/a

--------------- 0 ----------------- Now we have to cases

s1 = 1/2 v0^2/a1 = 45.3m

s2 = 1/2 v0^2/a2 = 60.5m

In the second case, what is the speed at 45.3m? Fist we need to find the time (t2) at 45.3m. We use the integral again:

s1 = v0*t2 - a2*t2^2/2 (notice that I have used the slower accellaration a2)

This gives a quadratic equation for t2 from which we can find the speed

But to cut a long story short, I end up with the result

speed at 45.3m = v0*SQRT( 1 - 45.3/60.5) = 62mph*0.501238 = 31mph !

---------------- 0 ------------------

But more to the point, at 62mph he could have reacted 0.55 secs earlier, that would have solved the problem.

If it stops at 60.5, then the speed at 45.3 m

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Gordon H 14 years ago

In message , johannes writes

One of 'em is on the wrong side of the road, or has just spun.

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John Henderson 14 years ago

Even more to the point, he didn't. Consistent with his mental aptitude in which he "justifies" his tyre choice, he reacts slower.

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Gordon H 14 years ago

In message , Mrcheerful writes

I can understand that.

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Chris Bartram 14 years ago

I hope he's trolling.

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johannes 14 years ago

No, his argument was that 3 * 3.5m = 10.5m and he somehow had to use baby cars in order to solve the arithmetic. The cars were packed on a car transporter, so nose to nose was perfectly possible.

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SteveH 14 years ago

Honestly, having been around on usenet for a while, and frequenting a few of the same groups as he does, he's a fully signed up foil hat wearing looney.

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Mike P 14 years ago

On Wed, 28 Mar 2012 18:09:46 +0100, johannes drooled:

Who gives a s*it what the distance between the cars is? It makes no difference if there is *no* cars in front of you if one suddenly appears from a side road, or do your cheap and nasty tyres have some magic car- repellent in them?

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Mike P 14 years ago

On Wed, 28 Mar 2012 18:09:46 +0100, johannes drooled:

Who gives a s*it what the distance between the cars is? It makes no difference if there is *no* cars in front of you if one suddenly appears from a side road, or do your cheap and nasty tyres have some magic car- repellent in them?

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Mike P 14 years ago

On Wed, 28 Mar 2012 18:09:46 +0100, johannes drooled:

Who gives a s*it what the distance between the cars is? It makes no difference if there is *no* cars in front of you if one suddenly appears from a side road, or do your cheap and nasty tyres have some magic car- repellent in them?

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