A Question About Performance Tyres? Ask The Michelin Expert!

[asharb123]

Jamie,

when should you fit winter tyres? I've been driving for over 20 years and never considered or knew anything about winter tyres and am now worried about this as I now have a family.

Ashar

[Jamie McWhir]

Ian

tram-lining is basically the tyre following the grooves worn in the road by trucks or other heavy vehicles.

The wider the tyre then the wider the contact patch, therefore increasing the likelihood statistically of finding a groove

Equally the shorter the sidewall height (aspect ratio) the more direct the movement from the tyre back up to the wheel. Hence a wide low tyre will always be worse than a tall narrow one.

Always bear in mind that due to road camber and UK road layouts, the most common form of wear is the outer shoulder of the NSF tyre. (you only go round roundabouts in one direction for example...)

[Jamie McWhir]

Jamie,

when should you fit winter tyres? I've been driving for over 20 years and never considered or knew anything about winter tyres and am now worried about this as I now have a family.

Ashar

Ashar

we say when you start seeing 7 celcius or lower on the dash (or if you hear it on the news if your car doesn't display a temp..)

That doesn't mean the tyres only work below 7, it's just a fair representation of the temps you tend to see October through to March/April time..

You don't need to wait for it just to snow.. they work particularly well on a winter road that's cold and damp

[Captain Fizz]

To expand on that (if I may)...

Summer tyres have a rubber compound that gets significantly harder once the temperature is below 7°C. (Significantly in the scientific sense, not observable other than via braking distances)

Most grip is due to the tyre moulding itself around the roughness/imperfections of the road surface, if the tyre hardens, less grip is a result.

An extreme example - Black Ice is an almost perfectly smooth surface, which tends to have next to no grip. (near 0 friction coefficient).

There are no imperfections / roughness for the tyre to catch on / deform round.

Winter (or all-season) tyres remain soft down to... Um... Much less than 7°C. (No idea :D)

So if the temps are below 7°C during your commute / main driving times, that is when a winter/all season tyre would provide higher grip / safety irrespective of snow.

Thanks for the explanation Jamie, I just thought cross-ply / radial etc also affected tram lining to a lesser extent.

[Surfcoast]

Hi Jamie,

I have a 2006 Lexus SC430 just back from service running and handling fine but it will very shortly need new rear tyres. Rather than have what the dealer has available I have decided to start switching over to one consistent manufacturer and model.

We live in the south of England and Tyre size is 245/40/R18. Decided on Michelin but could do with some advice on the final choice.

Pilot Sport 3 - 245/40 R18 Y (97) E,A and 71DB and have also seen the 93 rated version but this takes full economy down to an F (but is this really a big difference)

Other choice is the Primacy HP - 245/40 R18 Y (93) E,B and 70DB (lower noise rating )

Hope this makes sense .

Best regards

Neville

[Jamie McWhir]

Neville

Thanks for your post

I'd actually advise you to wait a couple of weeks if you can.

We are launching the Primacy 3 in 245/40-18 at the start of June (product code..199410), as it gives you the best of both worlds.

It's a good step forward over the Primacy HP and has a great level of grip wet and dry.

Unless you drive the car "hard" I'd go with this one over the Pilot Sport 3

any further queries, or if you struggle for availability, let me know

[PCM]

There has been much discussion on Michelin Latitude HP Tour's on the RX thread, and how much people like them - me included.

They have a M&S marking also.

It would be interesting to hear thoughts on their winter suitability...

[Jamie McWhir]

Hi

The Latitude Tour HP is a good all season type of tyre

Whilst it doesn't have the deep snow/heavy winter capability of the Alpin range, it's good on light occasional snow, and copes well with temperatures down to around -20. So for UK winters it's more than capable

It also gives a good level of wet performance, which to fair is what we experience for the majority of the winter

Also has a better performance if you go occasionally off road, so anything from wet grass, to sand and light mud.

I've recommended it to many consumers over the years, and never had one come back saying they hadn't found it to be a good tyre for their needs.

[Surfcoast]

Hi Jamie,

Many thanks for taking the time to reply. I rarely drive the car hard so will see what availability I can get on the primacy 3. Best regards

[Surfcoast]

Hi Jamie,

Supplier has been onto Michelin about the Primacy 3 who have confirmed that there is no price as yet and that the 245/40/93Y will not be available in the UK for 8 to 10 weeks.

I will not be able to wait that long, so is I am assuming that the Pilot Sport 3 is my best option in a 93 or 97Y. The 97Y seems to give a better mileage rating and is cheaper but is there any down side ?

Any thoughts much appreciated.

Best regards

Neville

[Jamie McWhir]

Neville

How worn are the tyres on the car at present?

In what way do you think the XL (97) load tyre will have a better mileage?

It's fairly irrelevant..

[Surfcoast]

Hi Jamie,

I had them checked at my MOT two weeks ago and was told that the two rears were very close to the limit. As far as the fuel economy I was going with the 93 showing as an F with the 97 as an E but I am not really sure how much of a difference this makes in real terms.

Best regards

Neville

[Jamie McWhir]

Well

If you really need to change them, then go with the PS3's. If they are still at 3mm or better they would probably be ok until the Primacy3 arrives. What I would say if the rears were too worn you'd have failed the MOT

On the Fuel efficiency, it comes down more to testing differences between standard and extra load tyres, the actual difference in service wouldn't be significant.

Are the rear tyres on the wear bars? If you don't do big mileage, then you could wait for the Primacy3 if they aren't

[Surfcoast]

Hi Jamie,

Checked today and under 2nd so I will need to do something this week. I will go with the Pilot Sport 3. Since there seems to be little difference in the 97 or 93 I will go with best price. Many thanks

Neville

[Surfcoast]

Hi Jamie,

I have had the Pilot Sport 3,s (for some reason they fitted the AO version) on for over a week now. Cannot explain why but overall handling of the car feels more precise. Possibly also helped by the discs being refurbished during the MOT. Radio volume is also down a couple of notches on one particular road !

Best regards

Neville

[lexom]

Hello Jamie,

Really enjoyed reading your responses to members' questions. It has been very informative.

Just one quick question: us (very recent) RX450h drivers riding on 235/55/r20 tyres have limited tyre options. Will the Cross Climate 2 be coming out in this size any time soon?

Many thanks.