Van tyres - KwikFits opinion

[mikejkay]

Having read some positive reviews I have chosen to replace my Michelin Camper tyres with Nexen Roadian CT8 tyres.

 

Spec: 225/75R 16C 10PR 121/120S Wet performance B, fuel economy B, noise 71dB.

 

I arranged with my local KwikFit for them to fit the tyres. I arrived, unloaded the tyres and carried them to the workshop. After a 1/2 hr wait a fitter came out took one look at the new tyres and the Michelins and then refused to fit them. He stated:

 

1 That it would be illegal to fit the Roadian tyres and the m.h. had to be fitted with "Camper" tyres.

2 That my insurance would be invalid if the Roadian tyres were fitted.

3 The load rating for the Roadian tyres was inadequate.

 

Is this b******t? Or is there a grain of truth in the dung?

 

P.S. This particular branch of KwikFit has been helpful in the past but I won't be going there again.

 

 

[witzend]

Spec: 225/75R 16C 10PR 121/120S

 

If this is the same as the old tyres then they are OK they don't have to be Camper tyres mine never where from new

[colin]

Those tyres are good for 2.8t on any axle, which could be up to 5.6t in total for van. AFAIK there are no Camper tyres capable of this loading.

[silverback]

as above the load rating is correct so whats their problem

Jonathan

*-)

[chas]

The popular term for KwikFit is also known as Quick s**t, how they still stay in business is beyond me, the true stories I have heard from my local garage of how they behave to some vulnerable customers both in pricing and "advice" is incredible. Once bitten.

[Mickt]

I have recently had fitted 4 Michelin camper tyres by Kwik Fit. They gave me the best price and fitted when is wanted them to.

[laimeduck]

I had Michelin camper tyres fitted by quick ..it as they had the cheapest deal but I agree with chas. They didn't know about valves & despite me phoning them to enquire they couldn't fit my motorhome on the ramp so had to jack it up in the road outside.

I tonk they are cheap & nasty!

[Derek Uzzell]

The specification for the equivalent Michelin “Agils Camping” tyre would be 225/75R 16CP 116Q or 225/75R 16CP 118R - so the Nexen tyre’s load-index of 121 indicates that it has a higher load-carrying capacity than either of the Michelin variants.

 

The ETRTO (European Tyre and Rim Technical Organisation) advises that motorhomes should be fited with tyres carrying the “CP” (Camping Pneu) marking, but this marking is an ‘identifier’ and has no ‘technical’ significance.

 

I’ve read in motorhome magazines suggestions that fitting “C”-marked tyres (like the Rodians) to motohomes that are sold originally with “CP”-marked tyres MIGHT have insurance-related implications as it would conflict with the ETRTO’s guidance. I’m pretty sure this idea was originated by Michelin (UK), but I don’t think insurance providers have ever been contacted for their views.

 

Some large motohomes (eg. Ford, Iveco or Mercedes-based ones) have never been fitted with “CP”-marked tyres when new, and it’s definitely not illegal in the UK to replace “CP”-marked tyres with “C”-marked tyres (nor vice versa) provided that the replacement tyres are suitable (size, load index, speed rating) for the motorhome to which they are to be fitted.

 

Given what I’ve said above, it’s quite likely that the KwitFit fitter believed what he/she told Mike, but

 

1: It’s not illegal to fit the Roadian tyres in place of the Michelins and

 

3: The Roadian tyres’ load-index is superior to the load-index of the Michelins - so, if the Michelins are OK for the Hymer’s axle-loadings, the Rodians will also be.

 

Regarding 2: Whatever Michelin and motorhome journalists might suggest, I’m not convinced.

[Keithl]

The Michelein's will be 8PR (as CP must be 8PR by definition of CP) and the Rodian's are 10PR so will most likely will have a stiffer side wall which may give a firmer or even harsher ride.

It will be interesting to hear your feedback on them after you have them fitted.

 

PS What pressures are you going to run them at? They will almost certainly need to be different to the Michelin CP's!

 

Keith.

[Billggski]

It could be an internal Kwik Fit memo to only fit original specification tyres due to liability issues?

[mikejkay]

Keithl - 2019-03-21 9:54 AM

 

The Michelein's will be 8PR (as CP must be 8PR by definition of CP) and the Rodian's are 10PR so will most likely will have a stiffer side wall which may give a firmer or even harsher ride.

It will be interesting to hear your feedback on them after you have them fitted.

 

PS What pressures are you going to run them at? They will almost certainly need to be different to the Michelin CP's!

 

Keith.

 

So far, after a short ride home :-D , the ride seems much the same, as is the noise level.

 

Pressures stated on the tyre wall are 83psi, a bit more than the Michelin. These are for a fully loaded vehicle. I have put in 75psi front and 80psi rear

 

As a matter of interest there was a noticeably greater wear on the centre of the Michelins, indicating over inflation although I think that for a lot of their life the tyres were run at pressures lower than those recommended.

[747]

I replaced the Michelin XC Camping rear tyres on my Tag axle van with Michelin Agilis Commercial tyres. They run at around 50 psi and are more than suitable. The 2 front (driving) wheels are Agilis CP. When I get round to it, I will have a Michelin Agilis CP fitted to the spare as it is now 12 years old but has never been used. That makes me covered for a puncture on any wheel.

 

ps: The only difference with an Agilis Commercial tyre is that it is not Mud and Snow rated like the Camper tyre.

[Keithl]

mikejkay - 2019-03-21 12:19 PM

 

Keithl - 2019-03-21 9:54 AM

 

PS What pressures are you going to run them at? They will almost certainly need to be different to the Michelin CP's!

 

Keith.

 

Pressures stated on the tyre wall are 83psi, a bit more than the Michelin. These are for a fully loaded vehicle. I have put in 75psi front and 80psi rear

 

As a matter of interest there was a noticeably greater wear on the centre of the Michelins, indicating over inflation although I think that for a lot of their life the tyres were run at pressures lower than those recommended.

 

Mike,

 

What are your axle weights in a fully loaded condition?

 

I ask as IMO your pressures are rather excessive, probably explaining the wear patterns you saw on your old tyres.

 

Michelin seem to always advise 5.5 bar (80 psi) for CP rears irrespective of axle load but that pressure in your Roadian's will support far more weight than the Michelin's by my limited reckoning.

 

eg Using Continental's on-line brochure, to support an axle load of circa 2,060 kg your new spec of tyre would only need to be inflated to 3.75 bar or 55 psi. A significant drop from 80 psi!

Even an axle load of 2,275 kg only requires 62 psi!

 

Look at pages 86 - 87 here...

 

https://blobs.continental-tires.com/www8/servlet/blob/85806/e0854f2c7866c64da551474b998ef8b3/download-technical-databook-data.pdf

 

If you haven't already then I feel you need to get accurate axle weights and contact Nexen for more accurate pressures.

 

Keith.

[Deffheads]

Hi, It's common practice now for Tyre dealers like Kwik Fit not to fit customer supplied tyres, as they say they can't guarantee them should you have a fault. I have encountered this with many motorcycle tyres I have purchased cheaper on the internet and try get fitted.

 

 

[mikejkay]

But, they agreed to fit them in the first place!

[aandy]

Derek Uzzell - 2019-03-21 8:34 AM

 

 

I’ve read in motorhome magazines suggestions that fitting “C”-marked tyres (like the Rodians) to motohomes that are sold originally with “CP”-marked tyres MIGHT have insurance-related implications as it would conflict with the ETRTO’s guidance. I’m pretty sure this idea was originated by Michelin (UK), but I don’t think insurance providers have ever been contacted for their views.

 

 

 

One has. I contacted my insurer some years ago when I changed from CP to C rated tyres. I think I was with Coast at the time but cannot be sure. They said it was of no relevance to the policy and that they did not need to be notified of such a change.

[mikejkay]

Mike,

 

What are your axle weights in a fully loaded condition?

 

I ask as IMO your pressures are rather excessive, probably explaining the wear patterns you saw on your old tyres.

 

Michelin seem to always advise 5.5 bar (80 psi) for CP rears irrespective of axle load but that pressure in your Roadian's will support far more weight than the Michelin's by my limited reckoning.

 

eg Using Continental's on-line brochure, to support an axle load of circa 2,060 kg your new spec of tyre would only need to be inflated to 3.75 bar or 55 psi. A significant drop from 80 psi!

Even an axle load of 2,275 kg only requires 62 psi!

 

Look at pages 86 - 87 here...

 

https://blobs.continental-tires.com/www8/servlet/blob/85806/e0854f2c7866c64da551474b998ef8b3/download-technical-databook-data.pdf

 

If you haven't already then I feel you need to get accurate axle weights and contact Nexen for more accurate pressures.

 

Keith.

 

Keith,

 

Thanks for the usefull information. The last time that I was able to check my weights in fully loaded travel configuration I was about 3,300kg all in. 200kg to spare :-D .

 

I recollect the spread being about 1500kg and 1800kg on the rear. I'm surprised manufacturers don't appear to publish tyres for given axle loads. The wear pattern on the Michelins certainly suggest that I have been drving with excessive tyre pressure for some time.

 

Curiously, todays driving would suggest that the Roadians give a slightly better ride than the Michelins. A bonus........on top of the £300 saving!

[Keithl]

mikejkay - 2019-03-21 5:08 PM

 

Keith,

 

Thanks for the useful information. The last time that I was able to check my weights in fully loaded travel configuration I was about 3,300kg all in. 200kg to spare :-D .

 

I recollect the spread being about 1500kg and 1800kg on the rear. I'm surprised manufacturers don't appear to publish tyres for given axle loads. The wear pattern on the Michelins certainly suggest that I have been drving with excessive tyre pressure for some time.

 

Curiously, todays driving would suggest that the Roadians give a slightly better ride than the Michelins. A bonus........on top of the £300 saving!

 

Mike,

 

Going by the Conti book your pressures should be more like 3.0 bar (44 psi) and 3.25 bar (48 psi) Front and Rear respectively.

 

As an example our AT weighs around 3,700 kg and while I don't have individual axle weights I run my Conti 225/70 R15 112/110R tyres at 48 psi Front and 60 psi Rear.

 

Keith.

[Billggski]

I'd look again at the sidewall pressure figures. That just seems wrong, I think white van tyres are usually marked 63psi max, and camper tyres have the same figure for some odd reason to do with the US market although they can go to 80.

[Deffheads]

mikejkay - 2019-03-21 5:54 PM

 

But, they agreed to fit them in the first place!

 

So who supplied the tyres? them our you?

[mikejkay]

Deffheads - 2019-03-21 6:18 PM

 

mikejkay - 2019-03-21 5:54 PM

 

But, they agreed to fit them in the first place!

 

So who supplied the tyres? them our you?

 

Me

[spirou]

Keithl - 2019-03-21 10:54 AM

 

The Michelein's will be 8PR (as CP must be 8PR by definition of CP)

 

Keith.

 

If I remember correctly from the continental tech doc linked above CP isn't limited to 8PR. It goes to 10 at larger sizes/load ratings.

[Derek Uzzell]

Continental’s “CP”-marked tyres are all 8PR. The exception that proves this ‘rule’ is the VancoCamper pattern in 215/75 R16 size that carries a “C” marking (because it’s 10PR) not the “CP” marking of all other VancoCamper sizes.

 

This anomaly used to be highlighted on Continental’s website, the explanation for it being given that the ETRTO had stated that - when the “CP” marking was introduced - this marking was only allowable for 8PR-rated tyres.

 

Ply-rating is an anachronism nowadays (at least in Europe) and best ignored. The load-carrying capability of the Roadian tyres mentioned in the original posting is given by the load-index (121/120), so the 10PR datum can be ignored. Equivalent size “CP”-marked tyres willl have a lower load-index value (so a lower load-carrying capability) and the fact that these tyres will be 8PR is superfluous.

 

The Ply-Rating system does not indicate how many ‘plies’ are used in the construction of the radial tyres that are now near-universal on road vehicles and, although the Roadian tyres are 10PR, that doesn’t automatically mean that their construction includes more ‘plies’ than an equivalent size 8PR tyre might have. The Roadian tyres MIGHT have stiffer sidewalls and, at the same inflation pressures, MIGHT provide a firmer ride quality than equivalent 8PR “CP”-marked tyres, but it’s not certain that will be so.

 

It’s obligatory in the USA for tyres to carry inflation-pressure data relating to the tyre’s maximum load-carrying capability. My Rapido motorhome has Michelin Agilis Camping 215/70 R15CP tyres and each tyre carries on its side-wall the advice “109Q at 80psi”, equating to a load-index of 109 (1030kg) and a speed-rating of “Q” (160km/h) - but that doesn’t mean I’m compelled to inflate my motorhome’s tyres to 80psi, any more than it means I’m compelled to drive it at 160km/h.

 

Michelin’s on-line Tyre Safety Guide says

 

MOTORHOMES:

 

Motorhomes require tyres are that are adapted to their conditions of use.

In 2003, the ETRTO (European Tyre and Rim Technical Organisation) changed

the standard ,as well as its recommendations relating to motorhome tyres,

and now says CP-type tyres have been designed to cater for the higher loads

imposed by motor-caravans”, and that "it is strongly recommended that motorcaravans

are only fitted with CP-tyres”.

 

At replacement, Michelin strongly recommends the fitting of CP tyres to

vehicles originally homologated and fitted with CP tyres.

The load on the tyre must not exceed its maximum limit for any reason, i.e. the

load rating must be respected.

 

The ETRTO also states that where CP tyres are used on the rear axle

(single fitment), they must be inflated to a pressure of 5.5 bar instead

of the normal pressure of 4.75 bar for example.

MICHELIN CP marked tyres are therefore specially designed to be driven

at an inflation pressure of 5.5 bar (550 kPa) This higher pressure improves

road holding and increases resistance to the challenging driving and usage

conditions encountered by motorhomes, especially with regard to loads

(occasional static and/or dynamic overload associated with this type of vehicle;

considerable rear overhang, load imbalance, high centre of gravity due to

highly positioned loads) and long-term periods of disuse.

 

Fitting tyres that are not adapted to this type of use could lead to:

- poor handling (roll, pitch, yaw, difficulties in road holding)

- in difficult or severe conditions, premature deterioration of tyre components,

such as the crown, which could lead to a rapid deflation.

 

In use: check and adjust if necessary tyre inflation pressures monthly and before

any long journey. Under-inflation can be dangerous: for example,

for the tyre size 225/70R15 Camping CP, an under-inflation of 0.5 bar/7.2psi

(11%) is equivalent to an overload of around 100 kg per tyre.

 

Overloading (even temporarily) or poor vehicle load distribution can cause

premature deterioration of vehicle components and/or tyres and thereby cause

damage to persons or property”.

 

If a change of tyre size is foreseen, a tyre of an equivalent overall diameter

should be used and the original load index and speed symbol should be

respected (speed and load ratings must be equal to or greater than the

original tyres). It is recommended that a tyre professional is consulted for this

operation.

 

If the vehicle is parked for a long time, do not leave the tyres under inflated,

and always make sure that the inflation pressures are correct before next

using the vehicle. Protect tyres from UV radiation, e.g. from sunlight, and use

axle stands to avoid tyre contact with cold winter surfaces (concrete, stone ...).

 

Have the condition of the tread and sidewall checked regularly (for impact

damage, cuts, cracking etc...) as well as the condition of the wheels and valves,

by a professional.

 

NOTE: For tyre inflation pressures above 4.5 bar (450 kPa), metal valves appropriate to

the pressures must be used.

 

The ETRTO documentation for their standards is not available on-line, so (unless someone is prepared to buy the relevant documents!) exact details of the “CP” marking standard won’t be known. Nor will it be known why the ETRTO is apparently insistent that a 5.5bar (80psi) inflation-pressure must be used for “CP”-marked tyres fitted to a motorhome’s single-fitment rear axle irrespective of the vehicle’s design and maximum authorised axle-loading, or how many ‘single-fitment’ rear axles it has, or the actual loading when the motorhome is being driven, nor why the “CP” marking should only apply to 8PR tyres.

[Brian Kirby]

mikejkay - 2019-03-21 4:54 PM

But, they agreed to fit them in the first place!

And whoever you spoke to has by now presumably been "re-trained" on company policy! :-D

 

Ring around local non-chain tyre fitting companies and explain what you want. Some just won't price to fit customer supplied tyres. I think most get a bit touchy if they haven't supplied the tyres, as they lose profit compared to supply and fit.

 

This, plus the liability issue, seems to be what underlies the chains' refusals to fit customer suppled tyres.

[Derek Uzzell]

I think the Roadian tyres have now been fitted...

 

(Last sentence of posting of 21 March 2019 5:08 PM above.)