V70 Wheels/Tyres: Winter Tyres

[Bill_56]

Originally Posted by Foreigner500

>>By the way winter tyres are not only for snow.

What are the downsides of winter tyres when its not wet or snowing ? I guess trying to understand how practical it is to drive on them all winter when actually conditions might only be bad 20% of the time.

There shouldn't be any real downside in winter. They are suppose do improve grip in all cold (not just frosty) weather conditions. I've seen it suggested that winter tyres are generally superior whenever the average daily temperature is 7 degrees or lower.

The rubber is a softer compound however, and if used in summer it may soften even more, to the extent that the tyre wears out too fast. That, together with the fact that winter tyres should generally need a minimum of 4mm tread, means you should switch back to summer tyres once the weather has warned up again. But it's not critical, it can wait till you can spare the time.

[kenny]

i fitted cooper mud and snow tyres to the front of my S80 last year, 225/45/17

thet transformed it, was able to tow a transit van up a long steep hill with no spin or probleems at all, would plough through 16 inces of snow like it wasn't there.
They cost me £94 each and were worth every penny, they are now in the shed and for sale hint hint £100 the pair will post at cost price.

[yoda960]

Originally Posted by Foreigner500

>>By the way winter tyres are not only for snow.

What are the downsides of winter tyres when its not wet or snowing ? I guess trying to understand how practical it is to drive on them all winter when actually conditions might only be bad 20% of the time.

I think part of the reason is that they are a softer compound (so they don't go rock hard below a certain temperature), this means they can wear out quicker than 'all weather' tyres.

[Gazdok]

Originally Posted by kenny

i fitted cooper mud and snow tyres to the front of my S80 last year, 225/45/17

thet transformed it, was able to tow a transit van up a long steep hill with no spin or probleems at all, would plough through 16 inces of snow like it wasn't there.
They cost me £94 each and were worth every penny, they are now in the shed and for sale hint hint £100 the pair will post at cost price.

If you fit winter tyres only to your driven wheels this may be great for traction because the rear wheels do not matter too much, BUT when it comes to braking the summer tyre axle can catapult you off the road in no time time and land you in the ditch at best.
The winter tyres on your front will bite and the summer tyres on the rear will loose contact a) because of the wrong rubber for snow and b) because the dynamic weight shift forward further offloads them.
Spend another £190 for safety.

[v_matt_v]

Originally Posted by Foreigner500

>>By the way winter tyres are not only for snow.

What are the downsides of winter tyres when its not wet or snowing ? I guess trying to understand how practical it is to drive on them all winter when actually conditions might only be bad 20% of the time.

Winter tyres are designed to be more flexible in winter conditions (below 7-8 degree C) that's why the rubber is softer. The main tread blocks are filed with very small cuts known as sipes (I refered to them as lamels).
Tread sipes create little biting edges that aid snow traction. The sipes bend away more easily because larger section of the tread is sliced/cut into smaller sections.


In normal summer tyre one of the blocks would be as a hole block whereas in winter tyres it's additionally cut for more flexibility and for this biting edge effect which more effectively removes snow, water or cuts through the ice when in contact with the boundary layer of either snow, ice or water - the tyre is more sticky you could say. The boundary layter is the most crucial part for the tyre to remove the obstacle (water, snow or ice). If it's not effective the tyre will lift off (I think it's called aqua-planning) and will be travelling over the water with no contact with the ground.
Additionaly when the expanded tread goes back to normal postion after the part of the tyre lost the contact with the ground (the wheel is rotating) then the excessive snow or water is pushed out from the tread. That's why with winter tyres you see the snow splashing away (the same with water but more difficult to spot) when the wheel is rotating.
A very general idea of winter tyre is like a pump which is pumping out the snow or water. It's the same thing with summer tyre but due to harder compound and less holes in the tread the water or snow removal is significantly less efficient. That's why quite often winter tyres are also narrower - it's more easy to remove the water or snow from a slimmer tyre sideways because most of the water is removed sideways anyway.

The winter tyres should be used only during winter season becasue due to softer compound you've got more grip which means there is more friction and this means lower fuel economy and higher wear.
I'm not sure to what 20% of bad conditions you're refering to. Winter tyre is also far better in wet conditions compared to summer tyre. There is a lot of rain and low temperatures in UK during winter.

That's a long explanation. I hope it makes sense.

[MrP]

i dont think this got answer from my earlier post, but what rims can i use???

obviously volvo ones (s60, v70, s80 i assume, what about 850, P1 S70/V70 or V40/50 rims?)

but what rims from other cars can i use, will ford ones fit, or am i just stuck with volvo rims?

[Bill_56]

Originally Posted by MrP

i dont think this got answer from my earlier post, but what rims can i use???

obviously volvo ones (s60, v70, s80 i assume, what about 850, P1 S70/V70 or V40/50 rims?)

but what rims from other cars can i use, will ford ones fit, or am i just stuck with volvo rims?

If you can find another rim that matches the Volvo offset, hub bore, and bolt pattern then you should be able to use it. Realistically, that means you have to tread carefully if you deviate from Volvo originals. Don't believe anybody who tells you that hub-bore or offset don't matter, they do.

If you're on a tight budget, then you can save on rims by buying winter tyres bundled with rims, which work out very cheap. Plus, you save on fitting costs as they are supplied fitted and balanced. For example, see:

http://www.mytyres.co.uk/Steel_wheels.html

As I already said, I can't vouch for the accuracy of mytyres' wheel dimensions as their helpline didn't understand my questions, though I suspect they are probably OK.

Alternatively, you could get lucky and find a used set of Volvo alloys on ebay. The trouble then is, if you slide into a kerb and damage one, you may not be able to find a matching used replacement so easily. The only quick fix then may be to buy a brand new alloy at full price. Ouch!

[kenny]

Originally Posted by Gazdok

If you fit winter tyres only to your driven wheels this may be great for traction because the rear wheels do not matter too much, BUT when it comes to braking the summer tyre axle can catapult you off the road in no time time and land you in the ditch at best.
The winter tyres on your front will bite and the summer tyres on the rear will loose contact a) because of the wrong rubber for snow and b) because the dynamic weight shift forward further offloads them.
Spend another £190 for safety.

Very valid point, however i was on a tight budget last winter and to be hounest i did not ever feel the backend twitch.

[Voyager03]

Originally Posted by Bill_56

If you can find another rim that matches the Volvo offset, hub bore, and bolt pattern then you should be able to use it.

What is the 'Volvo offset, hub bore, and bolt pattern'?

[Bill_56]

Originally Posted by Voyager03

What is the 'Volvo offset, hub bore, and bolt pattern'?

The offset depends upon the specific model and the width of wheel fitted. For My S60, the correct offset (confirmed with my parts dept) was 43mm for 6.5x16 wheels.

If you put your details into the 'mytyres' link I provided earlier, and then click on (any) one of the results, it will list what they believe to be the recommended wheel's parameters, eg 5 x 108.00 x 65.00 ET: 43.00. 5x108 is the bolt pattern, 'ET: 43' is the offset. I think (not certain) that the '65' is the hub bore.

The mytyres calculator got it right in my case, but I'd strongly suggest you check the calculator's proposed dimensions with a main-dealer's parts dept.

- Bill

PS: I just noticed, if you google for wheel bolt pattern, you get a long list of sites offering dimensions for different manufacturers and models. Some of them may be accurate.