Kumho WP71 / Oponeo

[2Btoo]

Hi,

I've just had some new tyres fitted to the rear of my car. It's a 987 Cayman and it runs on 17 inch wheels which did have Conti Winter Contact tyres all 'round. I bought these wheels with part-worn tyres already on them and have run them for the last couple of years (I didn't change them during the summertime).

The rears were worn out and I have (this morning) had some Kumho Wintercraft WP71 tyres fitted to replace the Winter Contacts. And I am really quite unhappy about the way that they perform; the rear of the car feels most unstable on them, almost as if it is running on blancmange. You can feel the rear move around and it's most off-putting. Whether this is the tyres moving on the road surface or simply the (new, huge, very soft) treadblocks moving around I don't know; my suspicion is that it's the latter but I'm not inclined to push the car hard to try this theory out. The car feels most unsettled and unstable at speed in a way that it didn't before and doesn't engender confidence at all.

The tyres were bought from Oponeo and fitted by a local fitter and I have no grumble about the service provided by either of them. It seems that Oponeo will take back the tyres within 14 days and charge me £15/tyre for transport, plus I'll have to pay to have new ones fitted (so the cost to me is about £60). I'm just about the tightest person you'll ever meet but I'm seriously considering this as an option given how bad the new tyres feel.

My question is whether I can expect the tyres to improve significantly with use? Is there anything about new tyres that makes them feel wobbly, but which improves with time? I understand that as the tread blocks wear they will settle down but this will take time and miles. Can I expect a swifter improvement from the tyre compound, or any kind of surface treatments that may have been put on them? Or is my best bet to pony up the £60 and change for something better?

Thanks.

[Smint]

Many new tyres need to scrub the initial layer of slippery stuff off before they perform as they will later, the only exceptions on winter tyres to this i've found were Vredestein Wintracs which were brilliant from the moment fitted, so good in fact that my Mrs tried her best to get me to leave them on all year round, all others required anything from 200 to 1000 miles to attain their best performance, lorry tyres can be up to 5000 miles before full grip is found.
Its also not yet cold enough for full winter tyres to be in their ideal temperature range ie below and considerably below 7'.
You have checked the pressures are right from the chart on the car or in the handbook, some cars on winter rubber/sizes need slightly lower pressures.

Your problem of course is that Oponeo won't want them back after several weeks running, in all honesty i'm not sure if they'll be that happy about them even showing signs of being fitted/driven at all, but presumably you've already checked on that.

I don't have any experience with the make you've bought, not through make snobbery but not sure i'd fit anything except a decent well known european make of winter tyre to such a car as you own, not as i'm against far eastern makes, have Falken summers on our Forester XT and rate them highly, but your car is on a different level completely to a Subaru that really anyone can drive swiftly because grip levels are so high.

[2Btoo]

Smint,

Thanks. Your comments about initial slippery stuff is helpful.

Pressures are 37, as per the handbook. (That's to say that I assume they are - it's what I asked the guy who fitted them to inflate them to and he was diligent in all other respects).

Yes, temperature outside was 12DegC this morning so they won't be at their best. However the ones that came off (also winter tyres) were very much better.

Having read the Oponeo T's&C's carefully it seems that the only restriction is that the 'cancellation form' is completed within 14 days of the delivery of the tyres and there is no mention of them having to be new and never mounted.

I take your point about snobbery but have had excellent experiences with Kumho tyres on Porsches before and rate them very highly indeed. (In fact I recall enthusing to anyone who would listen - or read - about how much better Kumho KU-somethings were than some outgoing Conti Sport Contacts on the rear of my old 944 a good few years ago, hence my choice of Kumho tyres this time 'round.)

Thanks again for your help.

[Smint]

Not sure i've been any help at all, but you're welcome.

Regarding Oponeo taking them back, i'd be inclined to drop them an email stating they've been mounted and run, would hate for you to send them back only for them to refuse re-imbursement once they see the signs of fitment and use, better to be up front on this i think.

The Contis will have been better (probably not in snow due to worn out) because most of the sipes worn away.

I've started to come away from full winters myself now that all seasons have come of age, running snowflake stamped Yoko all seasons on the Prado which are so good in all weathers i'll almost certainly replace like for like.
Still run second set of winters on the Subaru purely because we still had them from the previous Outback and they are recommended winter size for the Forester too, plus save the good wheels from winter salt bath, but when both sets have done their time all seasons it will be on that too.