Quote:
Originally Posted by barbel
No it's sir not madam - not sure how to prove that on a forum though http://e84.xbimmers.com/forums/image...happyanim.gif- but no such formality required!!
Mario, re the winter tyres. I guess my environment is a bit different from yours. At home here (Nimes) snow and ice are so rare as to be discounted. It can be torrentially wet though, in the autumn/winter. However, during the winter months I would expect to spend several weekends and a couple of longer trips in the mountains. The alps and pyrannees are each a 3-hour motorway trip from home. I've never used winter tyres before. Based on this lifestyle, would you recommend that I switch to winter tyres for dec-mar... and if so, do these wear out fast - bear in mind that even in the winter months, the majority of my driving would still be on dry, non-mountain roads.
also, what is the practical way to switch tyres - do you get a garage to switch them for you, or do you need to keep another set of wheels?
Your advice is much appreciated, |
Oops sorry...sir..
Its just I knew a german lady called Barbel
many years ago....But loooong story and wrong forum....
Back to the tyres...well it depends. There are four main types, summer tyres, which you find on most cars these days. All season tyres, which are a mix of summer and winter. Mud and Snow tyres (winter tyres marked M&S or a little mountain symbol) and lastly studded tyres for really icy, Nordic conditions. The studded ones are illegal in most southern european countries, including the UK, so you can discount them.
That leaves three choices; summer, combination or M&S. The main deciding factor here is of course your local conditions but the line between summer and winter tyres is roughly a road temperature of 7C. A common fallacy is that winters are only for when you encounter snow and ice, this is not true. As the road gets colder normal summer tyres get harder, to the point where you start losing grip. Best example is in F1 racing where you can see how poorly the driver’s times (and handling) are on cold rubber. Winter tyres have a much higher silica content which means they remain pliable at very low temperatures. Another rough guide is that at 0C winter tyres will give you around 30% shorter braking distances than the summers, quite a difference. Another interesting, and little known, fact is that summer tyres actually wear faster at low temperatures, the rubber becomes brittle. The converse is also true of course, winter tyres wear faster when the road gets hot. So, if you are going to be doing a fair bit of driving on road temperatures below 7C, you should be on winters. Always above 7C, use summers. The All Season tyres are a bit of an in-between. An option if you are looking for a single set of wheels but they are a compromise both ways. Also not so easy to get hold of in the correct size for a X1.
Lastly, just for completeness, winter tyres have a different tread pattern containing more cross tread than a summer tyre, which gives you the extra grip. The better tyres also make use of sipe technology. Difficult to explain but if you look at a winter tyre closely you will see that the tread itself is “cut” into hundreds of smaller blocks. These “cuts” or sipes causes the “blocks” to move independently of each other, giving grip and breaking up any compacted ice.
Where I live our road temperature falls below 7C around November and goes back up above this around March every year, so a good 4-5 months in every year. As a result I have a second set of winter tyres and rims. The winter rims are steel, mainly due to cost but also because I have seen how snow chains have scratched alloys. Everyone says good quality and well fitted chains should not scratch rims but the fact is they do. Incidentally, I went through BMW themselves for the winters as they have a service whereby they store my alternate set and do the swop overs free of charge. If you decide to stick to a single set of summer tyres I would suggest that you then rather invest in the better “rigid” type of chains, like those made by Thule (K-Summit). Also check to see whether there is any legal requirement to fit chains and/or winter tyres, I know some countries have quite strict rules on this.