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      11-21-2019, 12:56 PM   #1
ZedsRedBaby
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Winter tyres

I don't usually bother with winter tyres but these Pilots are definitely a bit slippy now the weather's getting cold. I don't really want to fork out for a second set of wheels but I'm struggling to find winter tyres that come in both sizes, so a couple of possibly dumb questions:

1. Does it matter if the front tyres are different from the rear? I assume not but I'm looking at Continental WinterContact where I can get TS860S for the rear and TS830P for the front.

2. Does it matter if the speed rating is lower than the summer tyres? The Pilots are 96Y and 100Y but winter tyres only seem to come in V rating. V is good for 149mph so probably OK?

Thanks for any guidance.
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      11-26-2019, 01:35 PM   #2
ZedsRedBaby
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If anyone else needs to know, it turns out the answers are:

1. No it doesn't matter as long as each side of the car has the same tyres and they're either all summer tyres or all winter tyres.

2. No it doesn't matter but strictly speaking you're supposed to have a sticker in the car stating that the car is not be driven above 149mph.
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      11-27-2019, 03:49 PM   #3
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I think our cars are limited to 155mph anyhow and I doubt very much that a tire that is good for 149mph comes apart when going 6mph quicker..... and I have to wonder how many of us will EVER drive our cars that fast anyhow; I'd guess most never break 120mph.

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      11-27-2019, 04:38 PM   #4
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The Michelin tires on our cars are not limited to 149mph. That is a common misunderstanding. Our tires are actually limited to 186mph - well above the 155mph limiter.

https://www.tirerack.com/tires/tiret...&affiliate=HM5

When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of vehicles that have extremely high top-speed capabilities.
W 168 mph 270 km/h Exotic Sports Cars
Y 186 mph 300 km/h Exotic Sports Cars

While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed.
225/50ZR16 in excess of 149 mph, 240 km/h
205/45ZR17 88W 168 mph, 270 km/h
285/35ZR19 99Y 186 mph, 300 km/h

When the Y-speed rating indicated in a service description is enclosed in parentheses, such as 285/35ZR19 (99Y), the top speed of the tire has been tested in excess of 186 mph, 300 km/h indicated by the service description as shown below:
285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 (99Y) in excess of 186 mph, 300 km/h

As vehicles have increased their top speeds into Autobahn-only ranges, the tire speed ratings have evolved to better identify the tire's capability, allowing drivers to match the speed of their tires with the top speed of their vehicle.
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      11-27-2019, 05:40 PM   #5
ZedsRedBaby
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Quote:
Originally Posted by DPelletier View Post
I think our cars are limited to 155mph anyhow and I doubt very much that a tire that is good for 149mph comes apart when going 6mph quicker..... and I have to wonder how many of us will EVER drive our cars that fast anyhow; I'd guess most never break 120mph.

Dave
You're probably right about the 6mph tolerance, but last time I drove to Germany I hit 145 on the autobahn so it would be a bit close on V rated tyres.
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      11-27-2019, 05:42 PM   #6
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Quote:
Originally Posted by SakhirM4 View Post
The Michelin tires on our cars are not limited to 149mph. That is a common misunderstanding. Our tires are actually limited to 186mph - well above the 155mph limiter.
I think you're referring to Y rated summer tyres? Winters are rated V (149).
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      11-27-2019, 06:05 PM   #7
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Quote:
Originally Posted by ZedsRedBaby View Post
I think you're referring to Y rated summer tyres? Winters are rated V (149).
You are right - sorry.
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      11-27-2019, 06:22 PM   #8
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Quote:
Originally Posted by SakhirM4 View Post
Quote:
Originally Posted by ZedsRedBaby View Post
I think you're referring to Y rated summer tyres? Winters are rated V (149).
You are right - sorry.
No worries. Thanks for the reply anyway

Looks like I'm going to put winters on and just be a little bit restrained if I do the Germany run this year
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