Tyre Speed Ratings

[julesg007]

Hi,

Got some pretty cheap tyres that will need changing (Infinity INF-05 front and Federal SS595 rear), but wanted some guidance on speed ratings.

The manual states that I should be using W rated tyres (168mph) and those fitted are W rated.

So, the question is should I stick with a W rated tyre or could I drop back to say a V rated tyre (149mph) or even a H rated tyre (130mph).

Both of the lower speed rated tyres are way above the legal limit and I'm not planning to hitting a German Autobahn, although I do suspect tthe car can go faster than the H rated tyre but won't be going anywhere near that speed.

Thanks for the help

 

[television]

I read on a tyre web site recently said that you do not have to have the max speed rated tyres on your car, this must be so for there are hardly any winter tyres with a speed rating of over 100 mph made

 

[drivinggod09]

stick with the w rating if thats what it came out of the factory with ive heard storys that some insurances check these things in the event of a claim not sure if its true

 

[jberks]

The cost difference are going to be minimal if they even exist. If the car is intended for W, then stick to W. As Malcolm rightly says it doesn't really matter but as there is no benefit in not doing so, why switch and risk the wrath of the insurance company.

BTW - I don't know infinity but the Federals aren't cheapies, they're upper-mid range tyres that give Bridgestone and Continental a hard run for their money. (They're actually better IME) They just don't advertise heavily in the UK so can't charge premium prices. A quick trawl on the "Scubi" and Alpha' sites where the 'turbo nutters' reside and you'll find them highly rated. That said, you can't beat Michelin for longevity and long term value for money.

 

[television]

For what it is worth the Police use W rated tyres across their whole fleet

 

[television]

I have come back to this to say that the cars weight/ load idex is almost more important,my car requires a 98 you are asking for trouble if you cheat on this one

 

[julesg007]

Hi all,

Thanks for the advice and information - will stick to W rated tyres and correct load ratings (91 per my owners manual)

Will concur that the Infinity is a cheaper option than the Federal but my god are the Federals noisey as hell - so bad I thought I had wheel bearing problems - they also pulled the car to the left and had to fight to keep the car straight. They also became stepped on the inner edge.

Just as well I have the same size wheels all round so at least I managed to swap the wheels around. The noise and the pulling has all but dissappeared, at least the car is now a much better drive.

Still haven't finally decided on brand just yet - the car won't be doing much mileage and I don't drive on the edge so something that performs well in all areas is what I'm looking for.

Been on a number of the web based tyre suppliers and I can get pretty good braded rubber for less than £80 per corner (205/55/16). Will need to start reading some reviews.

Heard good things about Avon ZV5 and Firestone TZ200, but I must say the new Goodyear Optigrip does seem very interesting.

 

[television]

Kwikfit are the cheapest on line by a long way on all of the searches that I have done in the last few days, and a 30% discount on 4 tyres on top

 

[television]

Take a look

http://www.kwik-fit.com/tyre-search.asp

4 Pirelis P6000 £69 each
firestone £57 each

 

[doversole]

This is all good advice and safety first too.

May i just add, the speed rating also takes into account the cars accelleration capabilities.
You wouldn't want traction 'breaking away' during an evasive manoeuvre.

DoverSole

 

[julesg007]

As always very good advice - making owning a MB that much easier.

Well I have learnt something new - Kwikfit aren't as expensive as expected, especially for the Firestone TZ200's.

Will sort out some new rubber soon.

Thanks again for the help

 

[David Nock]

I had a Mondeo a few years ago and queried the speed ratings for replacement tyres with Ford Technical.
Their reply was that you must fit the speed ratings given in the manual for two reasons:
1. Insurance is void if you deviate from makers spec and do not advise the insurance company.
2. You cannot know categorically that your car will never be on the autobahn during the life of those tyres. That is why Ford fit tyres to the vehicle's limit and not to the speed limit required in Britain.

 

[television]

I had a Mondeo a few years ago and queried the speed ratings for replacement tyres with Ford Technical.
Their reply was that you must fit the speed ratings given in the manual for two reasons:
1. Insurance is void if you deviate from makers spec and do not advise the insurance company.
2. You cannot know categorically that your car will never be on the autobahn during the life of those tyres. That is why Ford fit tyres to the vehicle's limit and not to the speed limit required in Britain.

I agree David that this info was put out some years back, but info on tyre web sites say that this is not true, one reason being the Winter tyres are only good for up to say 90 mph.

 

[julesg007]

The reason I asked the question was 2 fold:

1) The speed ratings seemed excessive in comparison to the actual speed generally driven at although.

Whilst I am aware that the max speed of the car is 149mph and only W or higher can handle this speed, I suspect that the vast majority of drivers will never get anywhere near the top end of the cars performace.

Far too dangerous on our crowded and poorly maintaned roads.

2) I did read on a web site that said it wasn't a requirement to replace with the same speed rating.

If I find the information, I'll post the link.

Of course it would be foolish boardering on the insane the drop to a much lower rating say an R rated tyre (106mph) when you know that you may be at some time travelling in excess of this speed,

Costs do vary between ratings but not by a huge amount but it wasn't a cost driven question.

Thanks again and regards to all

 

[David Nock]

OK folks, I stand corrected. Thanks for the flick with the wet towel Malcolm.

 

[television]

OK folks, I stand corrected. Thanks for the flick with the wet towel Malcolm.

I thought the same as you until a few weeks ago, its hard sometimes and not always possible to find other reasons why something written should not be so

 

[Alex M Grieve]

2) I did read on a web site that said it wasn't a requirement to replace with the same speed rating.

A point which reaches wider than this debate is that higher performance cars are exactly that. They have a considerable margin of acceleration, speed, cornering and braking which may never be used but provide a significant comfort zone when operating under normal conditions.

Let us assume that you are bowling along the M something in your MB @ 70-80 mph. You have large margins of all of the above up your sleeve. The driver in the Fiesta 1.1 Ghia who is flashing to overtake does not. He might pass you going downhill with the wind, but going the other way he can not.

Now add a howling wind and driving rain. His position has deteriorated significantly, yours has not changed. So we need to bear this in mind - I may be the slowest guy on the road on a dry day, but suddenly become the fastest guy on the same road in bad weather. It is then that I expect the higher spec tyres, brakes and suspension to keep me clear of, and allow for, the other motorists, who may well be at the limit of their envelope.

My preference is to stick with the manufacturer's spec and fit like for like - even if it was not a legal requirement.

 

[jeremy156]

Was hunting and found this - seems fairly black and white, so I thought I'd post this to the old thread to avoid doubt:

Section 16 point 7: The speed capability of all tyres fitted shall be not less than the maximum design speed of the vehicle.
from http://www.legislation.gov.uk/uksi/2001/25/schedule/3/made

 

[davidsl500]

You're 9 years too late !

 

[jeremy156]

I know.... but still a relevant topic, no? I use the forum as reference, so thought it worth closing out with clarity.