Technical Different-size winter tyres
- Thread starter roob
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Technical Different-size winter tyres
is the load index right for the sedici?
Hi I'm a tyre fitter. The speed index (letter after load rating) dosent matter with winters. They will fit the wheels fine, the aspect ratio (height) of sidewalk will be marginally smaller but perfectly safe
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Your joking right?
The Speed and weight ratings are very important just as getting the tyre size correct
The tyres you wish to fit are yes slightly smaller then the current tyres, your speedo will over read (for example your doing 30mph speedo, your actually doing 26mpg)
But Winter tyres are also stated in the Owners handbook to what level they must be acceptable
No point fitting a car that requires H speed tyres with R rated tyres, as the insurance company may refuse to pay out due to ""incorrect tyre fitted""
So please make sure the tyres are the same as whats stated in the handbook (or better!) just for peace of mind and so the insurance companies dont leave you high and dry
Ziggy
my book list Y for summer but as low as a H for winter. load index stays the same though
I've the speed rating below what's stated in my handbook on my winters. Still rated to 118mph, and I've no track days planned! Got the sticker on the dash so if the car is stolen and they kill themselves I'm not liable - always forward thinking!
Speed rating shouldn't affect insurance, but worth checking.
Speed rating shouldn't affect insurance, but worth checking.
dieselglider
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The load index for 205/60/16 tyres is 92, or 96 XL (extra load/reinforced ?). The load index for 205/55/16 is 91, or 94 XL. This equates to 630kg (92) vs 615kg (91) standard load rating per tyre, so I don't think there's any safety issue.
There will also be a difference in speedo reading of 3%, so at an indicated 60mph the car will be traveling 2mph slower than standard.
But, if you happen to have an accident, and the insurance assessor happens to notice non-OE sized tyres, there could be an issue.
There will also be a difference in speedo reading of 3%, so at an indicated 60mph the car will be traveling 2mph slower than standard.
But, if you happen to have an accident, and the insurance assessor happens to notice non-OE sized tyres, there could be an issue.
Thanks Dieselglider,
I think the answer is to contact my insurance company before fitting the tyres. No doubt they will try to make a charge of some kind. Might be easier just to stick the tyres on ebay and buy a set of 205/60s for the Sedici.
I think the answer is to contact my insurance company before fitting the tyres. No doubt they will try to make a charge of some kind. Might be easier just to stick the tyres on ebay and buy a set of 205/60s for the Sedici.
Caravadossi
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Let us have feedback on their comments.
A 3% speedo variation is insignificant & won’t get you into any trouble as you’re just adding in a further buffer to the designed-in speedo variation. The variation maybe greater if you’re not comparing like-with-like – e.g. new for worn (you don’t give your tread depth?).
If the winter are down to 4mm then probably good to offer on eBay to someone gullible – although I believe the AA argue that 3mm is the minimum.
121214
Don't forget that'll only be the view of one company, or broker most probably, and can change at any point so no-one should assume the same allowance would apply to them.
Caravadossi
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The tyre options will be in your OH – that I don’t have access to.
But as far as I can make-out the Sedici (& Suzuki SX4) wheel options roll within the envelope of 782(±9) revs/mile.
205/55R16 are marginally (<3%) outside that at 811 – but 205/50R16 at 838 are more (6%) of a step outside.
How come 205/50R16 were selected?
121214
Thank you Caravadossi for your helpful reply. I had the tyres fitted yesterday, and only when I got home did I notice the discrepancy in sizes. I have already noted a 6m.p.h. difference as against my g.p.s. at 50 m..p.h., and the Fiat supplier of the vehicle have told me to get them off immediately. The garage who fitted the tyres are going to put matters right on Monday; in the meantime will not be using car, as apparently the insurance is invalidated. These things happen.
