Issues running different sized alloys on same axle?

[Sump]

Buckled one of my 18" alloys. Purchased a used one from ebay, looked exactly the same and was 18".

Turns out the actual width of the alloy is every so slightly different to the buckled one. It's something like 2cm narrower but takes the same 225 40 18 tyre....

Is this going to cause me issues if I run this until I find a new set of alloys altogether?

[LukeR94]

It will probably be alright....probably



But you know what the PH brigade will say....

[Sump]

What are the actual issues with running it? I don't actually know.

[Scootersp]

do you know the offset of the new wheel compared to the older one, higher lower or the same?

[kambites]

As long as the offset is right for the car (so the tread sits in the right place relative to the hub) and the wheel width is within the guidelines for the tyre you're fitting, I don't see why it should cause a problem. I'd imagine any effect on the handling will be small enough to not be dangerous, although it might feel a bit weird because you'll get different amounts of side-wall flex left to right.

[steve_bmw]

If it's on the driven wheels the rolling radius must be the same, as it's the same size tyre I think you will be ok.

[Sump]

Dunno waht this means but on the alloy face it says.

The original is 8 - 50 and new one is 7.5 - 50

[shoehorn]

Sump said:

Dunno waht this means but on the alloy face it says.

The original is 8 - 50 and new one is 7.5 - 50

The figures relate to the rim width,if they are correct your difference is 1/2".

[davepoth]

It will make the car feel a little different from side to side - the sidewall not being at the same angle on the wheel will do that. It's not ideal by any means, but since it's apparently safe to drive on a single space saver up to 50mph I doubt it's going to make you explode immediately. I'd be on the look out for another alloy in one of the correct sizes though.

[fjord]

I know there's an offence of having different size tyres on the same axle, but not sure about wheels themselves.

[V8RX7]

I defy anyone to tell the difference on the road.

I've bought many sets of staggered wheels to find some genius has mixed them up with one wide tyre on a narrow rim etc

It'll be fine

[stesrg]

Hi you will find this app useful for your I phone search in apps wheel calculator , it tells you all the wheel rolling diameters and allows 20% so you will not wind up your diff !

[kambites]

Sump said:

Dunno waht this means but on the alloy face it says.

The original is 8 - 50 and new one is 7.5 - 50

The first figure is the rim width in inches.

[shovelheadrob]

I would think the second figure (50) is the offset

[HertsBiker]

fjord said:

I know there's an offence of having different size tyres on the same axle, but not sure about wheels themselves.

I heard that too... but how do space savers get approved for use?

[Krikkit]

HertsBiker said:

fjord said:

I know there's an offence of having different size tyres on the same axle, but not sure about wheels themselves.

I heard that too... but how do space savers get approved for use?

Emergency/temporary use only - much safer than having people drive around on flats/stripped rims.

[stesrg]

HertsBiker said:

I heard that too... but how do space savers get approved for use?

Its all about rolling diameter don't make any difference to wheel size !! you can dave a small wheel and a larger tyre to compensate

[fjord]

stesrg said:

Its all about rolling diameter don't make any difference to wheel size !! you can dave a small wheel and a larger tyre to compensate

One would assume, if you bought a car with 16's, then fitted 17's, your space saver would technically become illegal, as it would be a 16?