I have a 3 year old Corsa 1.2 Design fiited with Pirelli P6000 185/55 R15 on 6J by 15 H2 steel wheels. I recently needed to use the spare for the first time and was surprised to find it was a 175/65 R14 Continental Eco on a 5 1/2J by 14 H2 wheel. My initial thought was that was intended to save space in the spare well as it is 1/2 inch less deep - but more likely it's just the wrong wheel.
Any ideas?
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Did you buy the car new ?
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Bought 6 months old as ex Vauxhall company vehicle from with 2k on clock
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Could be that it had optional sized wheels retro-fitted and someone "forgot" the spare was a different size.
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Don't think so - I'm pretty sure 185/55 are standard for the model.
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Yep, 185/55 is standard size according to the Dunlop website.
Pretty sure reference has been made on here before, regarding a different sized spare. I think though as the rolling circumferance is the same, it can be used as a "get you to the nearest repair centre" type spare. ie, pretty much the same as a space saver really.
If I find the link, I'll post it up. Does the handbook say anyhting at all about it?
Edited by Dynamic Dave on 08/10/2007 at 01:47
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Just looked in an Aug 2003 handbook. It says "The spare wheel is designed for use as a
temporary spare. The temporary spare is designated by a sticker on the rim.
I can produce a snapshot of the relevant page (p.164) if you haven't got a handbook. Or you might still be able to download a free pdf version from the Vauxhall website once you've signed up (for free) to "My Vauxhall". If it's not there, then providing you have space on your mail server, I can email you across my copy (7.7MB or thereabouts). Just contact me on my moderators email address.
Edited by Dynamic Dave on 08/10/2007 at 02:18
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This is the correct spare wheel. It's not a 'spacesaver' which has a very narrow 125 size tyre, instead Vauxhall won't go to the expence or waste of providing a matching spare alloy wheel and tyre so instead provide a steel wheel with a tyre that is the same overall size as the alloy wheel, even though it's a fourteen inch steel wheel. It will be perfectly safe and give better grip than a temporary space saver.
Ford do the same on their Fiesta Zetec which has standard 15 inch alloys with 195/50 tyres but look in the boot and there is a black steel wheel 14 inch with 175/65 Conti tyre.
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It will be perfectly safe and give better grip than a temporary space saver.
If one wheel has better grip then don't you increase the chance of skidding?
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Chris, how I read it was the 'proper' spare wheel will give better grip that a space saver spare wheel.
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And on the SportKa which has large alloys but a std. Ka steel spare(same rolling radius)-the good thing is no speed restrictions tho' I would make sure the alloys were always on the front.
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>>tho' I would make sure the alloys were always on the front.
Why so?
Number_Cruncher
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Because I accelerate,decelerate and steer with the front wheels and I prefer instability at the rear not the front.
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jc2, you give exactly the answer I was expecting you to give. As you might expect, I don't agree.
First let's get the tedious point out of the way! Of course this is a preference thing, but most tyre companies would advise that if there were an instability it is more controllable at the front end - although I don't particularly want to open the perpetual debate on where to put freshly changed tyres, front or back.
More to the point of my question, I don't think having a slightly different sized tyre of the same rolling radius necessarily means instability. If the tyre pressures in each tyre are the same, the contact area with the road will be virtually the same. With the modest changes we are considering, for most people who do not have the level of sensory feedback of a racing driver I would challenge them to even be able to tell.
I would expect there to be far greater differences in available grip side to side from variations in a typical UK road surface, from diesel spills, manhole covers, white lines, and depressingly the ubiquitous botched road repairs and potholes.
However, I do agree with the MOT stipulation of same sized tyres across an axle - without some sensible baseline, there would be all sorts of lethal cobinations on the go. I'm thinking of cases where the rolling radius would differ, and with stiff suspensions some tyres might not have any vertical load at all while others would be overloaded.
Number_Cruncher
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Whilst not a racing driver,my work for 40+ years did include a fair amount of driving of ultra-high performance cars on race tracks,test tracks and the road-and,as I said,I prefer the front end to be stable on a FWD car.For RWD,it's different and for people just starting out on a driving career,I would agree it would be different.Spending a winter in the north of Finland,it is noticeable that many of the FWD cars there are only fitted with studs on the front wheels.
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Thanks Dave. There is a label on the wheel - but it doesn't say temporary spare - it says 185/55 - which it isn't. Anyway it does seem from other replies that this is the correct spare and that Vauxhall are just trying to save themselves a few pence.
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It's 'temporary' in as much as it doesn't exactly match the other three tyres on the car, and the car wouldn't pass an MOT with it in place. As it will potentially have a small effect on the handling of the car, in extreme circumstances it shouldn't be left in service for extended periods. However, the tyre is a 'normal' tyre without the particularly low speed and distance restrictions of the skinny space-saver spares.
JS
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John S,
It *might* pass an MOT. It depends whether the aspect ratio is smaller than the requirement to pass:-
www.motuk.co.uk/manual_410.htm
Reason for rejection:-
1a. One tyre is of a different nominal size or aspect ratio to any other on the same axle.
Note: Tyres with aspect ratios of 80% and 82% are almost indentical in size and can be safely mixed in any configuration on a vehicle. Where this is done, Reason for Rejection 1 does not apply.
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DD
Hmm. The wording is is key here. It says 'nominal size', not matching diameter. The profile example given shows an acceptable variation of 2 percentage points. This car has 15 inch road wheels and 55 profile tyres and a 14 inch spare with a 65 profile tyre. I think it is therefore clearly a different nominal size (15" v 14") and aspect ratio varies by 10 percentage points. Generous tester might say 'you will get that puncture fixed, won't you?' and pass it, but I wouldn't be hopeful!
JS
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Standard practice on Vauxhalls and others. Usually seen with alloy road wheels, but also with expensive tyres on stel wheels. It will have the same rolling radius as the road wheels. Check the handbook as indicated by other posters. Maybe not ideal but much better than a skinny, speed limited space saver!
JS
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