My much-travelled Xantia TD has parked me at the side of the road once too often, so it's departing this life and a much newer C5 HDI 2.0 16v joins the fleet at the weekend.
I was just looking at the likely tyre replacement costs for the new toy. 215/55/16W. Ouch. Does anyone know *why* the C5 runs on W-rated tyres? I thought that Citroen claimed 124mph or something, why does it need a tyre capable of 168mph? H or V would do just fine.
Cheers
Pete
Why does the C5 have W-rated tyres?
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Why does the C5 have W-rated tyres?
Xantia HDi 110 Excl Estate 140k
C5 HDi 138 Estate
C5 HDi 138 Estate
That is an interesting thought MikeT.... how-ever:
Me 'personally', I would not think that 100%, the size, width, acceleration (torque), cornering forces (especially on a hydropneumatic cars) are all factors to take into account.
I think it's all a balancing act of top speed vs. safety characteristics for a specific car. Meaning, the top speed rating is based on many factors, not just the stresses imposed on the tyre at top speed, it is a ballpark figure derived to achieve a theoretical top speed based on characteristics.
In saying that, my theory goes out of the window comparing the C5 to a 406.
My old Xantia V6 had V rated tyres even though the top speed is around 145mph. So a H would have done, which I did.
Me 'personally', I would not think that 100%, the size, width, acceleration (torque), cornering forces (especially on a hydropneumatic cars) are all factors to take into account.
I think it's all a balancing act of top speed vs. safety characteristics for a specific car. Meaning, the top speed rating is based on many factors, not just the stresses imposed on the tyre at top speed, it is a ballpark figure derived to achieve a theoretical top speed based on characteristics.
In saying that, my theory goes out of the window comparing the C5 to a 406.
My old Xantia V6 had V rated tyres even though the top speed is around 145mph. So a H would have done, which I did.
Why does everyone only look at speed rating?
It is only half the picture, tyres have a load rating as well.
You may well find that a V rated tyre will not support the mass of the car safely when fully loaded.
Check the load rating before you make any decisions on tyres based upon the speed rating.
To emphasise the point there are almost no H rated tyres with a load rating which is great enough for a laden 1.9Td Xantia
It is only half the picture, tyres have a load rating as well.
You may well find that a V rated tyre will not support the mass of the car safely when fully loaded.
Check the load rating before you make any decisions on tyres based upon the speed rating.
To emphasise the point there are almost no H rated tyres with a load rating which is great enough for a laden 1.9Td Xantia
Just re read your first post, they are w rated because they are a 55 profile, load rating reduces with profile. I'm fairly certain that the load rating of the tyre is correct for the car although the speed rating is excessive.
If you had a 65 profile then you could probably use v rated tyres
Heres a little table to show the load ratings
http://www.tyresave.co.uk/tyreload.html
note most tyres will say something like 81H or 88V, not just H or V.
Another point about tyres that really gets to me, when you have new tyres fitted insist that the red dot on the tyre alligns with the valve, it is the lightest part of the tyre and as such putting it by the valve will minimise the amount of weights needed to balance the wheel. I've only seen one pair of tyres fitted like this (correctly) in the last year or so.
It's amazing what a fitter won't bother doing despite the fact that it is very basic stuff that ultimately makes their job easier.
If you had a 65 profile then you could probably use v rated tyres
Heres a little table to show the load ratings
http://www.tyresave.co.uk/tyreload.html
note most tyres will say something like 81H or 88V, not just H or V.
Another point about tyres that really gets to me, when you have new tyres fitted insist that the red dot on the tyre alligns with the valve, it is the lightest part of the tyre and as such putting it by the valve will minimise the amount of weights needed to balance the wheel. I've only seen one pair of tyres fitted like this (correctly) in the last year or so.
It's amazing what a fitter won't bother doing despite the fact that it is very basic stuff that ultimately makes their job easier.