MX5Ireland

Hi
I fitted new 15x6" alloy wheels with Nokian 185x60x15 winter tyres today and decided
to compare the weight of these to the OE Mazda 16" ones I was removing.

The new 15" combination weighed exactly 15Kg or 33lbs The rim alone was 7.73Kg
The Mazda 16" combo weighed 15.64Kg or 34.4lbs

I had expected the Mazda 8 spoke wheel would have been lighter than that.

Tom

I would have imagined so too - given the way they promote their cars' weight saving features. It seems that 1 inch of extra circumference accounts for the extra .64 kg per rim, which makes it sound like you have got nice, light alloys for the winter tyres (are they Mazda rims?)

No the wheels I went for are actually just the cheapest ones I found on-line that I liked the look of.
https://www.oponeo.ie/alloy-wheel-detail/dezent-re-6-00x15-4x100-00-et44-00#21120412
I thought I would give the car a different look in winter, so I picked silver ones.


I think with these, the car looks lighter (more juvenile) and ready for fun. The darker wheels make
it look more serious and business like. Or maybe it's the smaller rim size that harks back to the early MX5s

Also after 200km driving on the roads that I use most every weekend, I believe these Nokian tyres
http://www.tyrereviews.co.uk/Tyre/Nokian/WR-D3.htm are quieter than the OE tyres
and also more comfortable on small bumps or rough surfaces.

Tom.

I kinda prefer silver wheels. They look great on the car - and interesting about the noise levels - wonder us it the brand or the fact they are winter tyres (I've never had winter tyres on a car).

It's because they are winter tyres.
Winter rubber is always softer for better grip in low temperatures. Non winter rubber goes hard in low temperatures and looses grip on the same surfaces on which they have good grip in warmer temperatures, even without snow or ice. It's also why they have to be removed when summer temperatures return,-or the handling will suffer and they will wear faster.


Since I got this car I have been following the US Miata Forum and there is an interesting thread there about this

https://forum.miata.net/vb/showthread.php?t=680947
It seems high performance summer tyres can crack if flexed below minus 7 deg C

The Miata.net Forum is always worth exploring.

could it be the weight of the taller tyre that is making the difference?

I went looking online for the weight of the OE tyres that I had removed from the car, but I didn't find an answer. But I did find this on TireRack.com USA website. (and also that they cost over 200 dollars each.)

Quote:
Yokohama ADVAN Sport V105 (Max Performance Summer): The ADVAN Sport V105 is Yokohama's Max Performance Summer tire developed for the drivers of high-powered sports cars, sporty coupes and performance sedans. Based on technology fostered through participation in motorsports and development at the Nurburgring Circuit in Germany (one of the world's most grueling race/test tracks), the ADVAN Sport V105 combines an increase in agile handling with a more comfortable ride when compared to its predecessor by featuring precision-tuned materials and structures. Like all summer tires, the ADVAN Sport V105 is not intended to be driven in near-freezing temperatures, through snow or on ice.


I underlined the last sentence. I had assumed that all new cars were delivered with All Season Tyres unless otherwise stated, I hadn't realised that the original tyres on this car were actually Max Performance Summer tyres when I wrote the post above about them cracking if flexed in freezing temperatures.
Also could that underlined sentence be took to mean that using these OE tyres in Irish winter conditions means that an insurance claim could be easily refused because the tyres were not being used within the manufacturer's guidelines? There might even be legal implications?

Maybe everyone should be checking the specifications of the tyres they are using and do some research into whether they are safe to drive on for the next couple of months. Last December I only had this car for a few months and didn't worry at all about taking it out on dry cold roads, even at minus temperatures.

There’s something about summer tyres not being as good under 7degrees
https://www.uniroyal-tyres.com/car/tyre ... -in-winter
Found a pretty good explanation of Tyre types and usage here
https://youtu.be/RU4O3ulin80
Says a lot about using full winters when not really needed

Those are the type of web sites I have been exploring lately. After my last post about my OE tyres I went back to tirerack.com and dug deeper. I discovered that they weigh 18 lbs new. So after 6000kms mine were probably 17.9 lbs. The wheel and tyre together are 34.4 lbs, making the 16 inch Mazda wheel 16.5 lbs or 7.5Kg

So the Mazda branded original 16" wheel is lighter than my cheap 15" wheel by just 8 ounces.
So long as 18 US pounds equals 18 imperial pounds, unlike their gallons which means their MPG figures have to be re-calculated to compare to ours. 40 US mpg ---48 mpg here.