True. Trouble is, the limiting factor is not rotating the wheels, but moving the weight of the vehicle, which is much, much heavier than the alloys. I'm sure an accurate enough dyno could spot the difference, but I seriously doubt any driver could in a blind trial. This would only matter if you jacked the car off the ground then raced the wheels alone.
Advantages and disadvantages of different wheel sizes?
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True. Trouble is, the limiting factor is not rotating the wheels, but moving the weight of the vehicle, which is much, much heavier than the alloys. I'm sure an accurate enough dyno could spot the difference, but I seriously doubt any driver could in a blind trial. This would only matter if you jacked the car off the ground then raced the wheels alone.
As the above is specified I'd say you need skinny tyres as they out perform anything else when it comes to snow.
Those that doubt me just look at the tyres on Snow/Ice racing cars & Rally cars when they do snow.
If you change the wheel size AND tyre size so the overall radius/diameter/circumference change, you're effectively changing the gearing of the car, that's what changes the rate of acceleration and top speed capability most significantly.
If you change the wheel size but have a tyre size that maintains an equivalent radius/diameter/circumference to before, then the effect of different rotational inertias etc. will be negligible.
If you change the wheel size but have a tyre size that maintains an equivalent radius/diameter/circumference to before, then the effect of different rotational inertias etc. will be negligible.
Reducing rotating mass is like fitting a lighter flywheel. It has a massive impact in the lower gears. It's not the mass reduction of the car that's giving the benefit.
Lighter wheels also let's the suspension work more effectively and the dampers have better control of the wheel. This will help improve ride
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I take your point about skinny tyres - last season I watched some woman turn up to work every day, regardless of how deep the snow was - she was driving a 2CVAs the above is specified I'd say you need skinny tyres as they out perform anything else when it comes to snow.
Those that doubt me just look at the tyres on Snow/Ice racing cars & Rally cars when they do snow.
Still, cool car though the 2CV undoubtedly is, I would like to get five steel wheels and winter tyres.
If it's specifically for winter tyres then definitely don't go for a larger diameter wheel. You may even find that your manufacturer recommends a smaller wheel for winter wheels. My S4 comes with 17" as standard but 16" is their suggested winter size.
The smaller wheel gives a larger (higher profile) sidewall which helps the tyre to conform to the uneven road surface you can get with compacted snow, especially if you lower the tyre pressures for extreme conditions when it'll lengthen the contact patch much more than a lower profile tyre would, giving you more rubber on the road.
In your case I'd check the handbook for the manufacturers recommendation, or at least stay standard
The smaller wheel gives a larger (higher profile) sidewall which helps the tyre to conform to the uneven road surface you can get with compacted snow, especially if you lower the tyre pressures for extreme conditions when it'll lengthen the contact patch much more than a lower profile tyre would, giving you more rubber on the road.
In your case I'd check the handbook for the manufacturers recommendation, or at least stay standard
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Agreed - sports low profile tyres are ideally suited to the snow/cold weather, and do not heat up enough to offer grip. When driving in a spirited manner a lower profile tyre will give you more feedback and better handling, but a larger tyre (smaller wheel) will offer you more comfort on rutted roads, but a little compromise on handling.
If I were in the Alps, and spending winter there, I'd go for the comfort and winter handling performance, rather than worry about a sport-centric type of tyre. In the summer though, that's different, but then again it doesn't seem as though you're after that sort of thing anyway.
If I were in the Alps, and spending winter there, I'd go for the comfort and winter handling performance, rather than worry about a sport-centric type of tyre. In the summer though, that's different, but then again it doesn't seem as though you're after that sort of thing anyway.
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Yesterday I spoke to a dealer about the spec of a car I had just test driven. When I asked about "smaller" wheels I was told that only larger wheels were an option on the car and as a result I would have a problem with insurance if I went with smaller wheels.
I 'phoned my current insurers who confirmed that this was the case even if the smaller wheels were supplied by the dealer with a new car. When I pointed out that these smaller wheels were standard on a lower spec version of the same car I was told that they still weren't the standard or optional spec wheels and as a result would involve an increased insurance premium.
MADNESS!
I 'phoned my current insurers who confirmed that this was the case even if the smaller wheels were supplied by the dealer with a new car. When I pointed out that these smaller wheels were standard on a lower spec version of the same car I was told that they still weren't the standard or optional spec wheels and as a result would involve an increased insurance premium.
MADNESS!