General 15 or 14 inch wheels.

[Theydon Mount]

Hello,
Just joined.
I’m looking for a 2012+ Panda and have seen a 2013 Lounge that looks good.
It has 15 inch wheels. Any thoughts on the benefits and drawbacks of these over 14 inch on the Easy and Pop?
Thank you.
T.

 

[jrkitching]

Hello and a very warm welcome to the forum.

The ride will be slightly harsher on 15" wheels, but not massively so. Wider tyres will slightly reduce fuel consumption, but not by enough to be able to measure.

I doubt most people would notice any handling difference in normal driving.

The actual brand and type of tyre fitted will likely feel subjectively more different.

It's only when you go over 15" that the ride becomes significantly compromised.

The only benefit to 15" alloys will be cosmetic, if that's the sort of thing that floats your boat.

Personally I've a preference for 14"steels over 15" alloys, simply because they're less likely to get damaged by potholes, and cheaper to replace if they do, but it wouldn't be a deal breaker if the rest of the car was what I was looking for.

On a used car, check the rims carefully for damage; Fiat alloys aren't the strongest out there, and a new replacement won't be cheap.

 

[Theydon Mount]

Hello and a very warm welcome to the forum.

The ride will be slightly harsher on 15" wheels, but not massively so. Wider tyres will slightly reduce fuel consumption, but not by enough to be able to measure.

I doubt most people would notice any handling difference in normal driving.

The actual brand and type of tyre fitted will likely feel subjectively more different.

It's only when you go over 15" that the ride becomes significantly compromised.

The only benefit to 15" alloys will be cosmetic, if that's the sort of thing that floats your boat.

Personally I've a preference for 14"steels over 15" alloys, simply because they're less likely to get damaged by potholes, and cheaper to replace if they do, but it wouldn't be a deal breaker if the rest of the car was what I was looking for.

On a used car, check the rims carefully for damage; Fiat alloys aren't the strongest out there, and a new replacement won't be cheap.

 

[Theydon Mount]

That’s great. Very helpful. The pothole thing and Fiat alloy replacement cost are relevant points for me. Not bothered about cosmetics of 15s. I was thinking of getting a real spare wheel too so I guess that would be pricier in 15” too.
I’ll keep looking.

 

[Bonefish Blues]

You'd have to be going some to damage a 15" rim on a pothole though.

 

[Theydon Mount]

You'd have to be going some to damage a 15" rim on a pothole though.

Noted. Thank you.

 

[jrkitching]

I was thinking of getting a real spare wheel too so I guess that would be pricier in 15” too.

If the car does not have one at all, you can buy a used 500 spacesaver spare, with the advantage that it is easier to fit into the boot. These were supplied new with many thousands of 500's, so are easy to obtain on the used parts market, and most will likely never have seen active service.

 

[Theydon Mount]

Ah. That is a good idea. It’s just got the fix and go. (Didn’t know the 500s had 15s).

 

[jrkitching]

(Didn’t know the 500s had 15s)

All but the most basic 500's had 15" alloys at least; some left the factory with 16" or even 17".

The spacesaver is actually 135/80x14, but the rolling diameter is almost identical to the 15" alloys. The only restriction is that you're limited to 50mph.

 

[Bonefish Blues]

Noted. Thank you.

I'm running 185/65 on 15s. Lack of weight and tallness of sidewall + plenty of volume means lots of cushioning, even on some awful roads near here.

 

[Theydon Mount]

Is it feasible to swap 15 inch alloy wheels for 14 inch steel? Just wondering.

 

[The Panda Nut]

You can change them over, but the speedometer is programmed to work with the size fitted originally and I haven't seen any facility in MES to alter it. You certainly can damage 15" wheels as easily as the smaller ones and the Fiat 15 inch wheel are £320 each! My repaired wheel is still not true and Im looking for a replacement secondhand at sensible money. The 14 in tyres are much cheaper. Even parking the 14 and 15" wheels side by side you cant see much difference.

The 185x15 fitted to our lounge and some easy models does feel more planted on the road, but only driven back to back. We have 2 cars on 15 and 1 on 14 inch. There is absolutely no difference apart from a slight feeling the wider tyre gives making if feel just a little like a larger car. The 14 inch and 15 inch alloys of 2013 are of the same rather nice pattern. Someone reported buying a set of 15" genuine Panda wheels for £70 a few weeks ago. Im still deep green with envy.

 

[jrkitching]

Is it feasible to swap 15 inch alloy wheels for 14 inch steel? Just wondering.

Yes. I did this with my 500 shortly after buying it new.

Also a lot of folks with 15" alloys get the 14" steels to fit winter tyres.

You can change them over, but the speedometer is programmed to work with the size fitted originally and I haven't seen any facility in MES to alter it.

There's no need for any reprogramming. 14" wheels have a different tyre profile and the rolling diameters are almost identical.

 

[PuntoHowTo]

Is it feasible to swap 15 inch alloy wheels for 14 inch steel? Just wondering.

Yes but you need to keep the same rolling circumference.

You can use a website like this https://tiresize.com/tyre-size-calculator/

on the comparison side of there app, enter your current tire size, then you can play with the second tire size to keep get as close as possible to the same overall size of the wheel. as an example

you have a 195/65/15 tire currently then a 185/70/14 would be about as close as you could possibly get to the same circumference. a -0.4% difference.
And if you had a super accurate set of dials in the car that read exactly 10mph at 10mph 20 mph at 20mph and so on.

When the dash reads 70mph, you would actually be doing 69.7mph you can play with that tool and see how it works.

One consideration is that many newer cars cannot go smaller than 14/15 inch wheels because the brakes and calipers are much larger than in the past and the wheels won't fit over the brakes. Diesel cars tend to have bigger brakes, so before down sizing look at the gap between the brake caliper and the inside of the wheel, to make sure there is a big enough gap.

Also Steel wheels are thinner than alloy wheels so if down sizing from steel wheels to alloy, the alloy wheels might not fit where as 14 inch steel wheels would.

 

[Theydon Mount]

Yes but you need to keep the same rolling circumference.

You can use a website like this https://tiresize.com/tyre-size-calculator/

on the comparison side of there app, enter your current tire size, then you can play with the second tire size to keep get as close as possible to the same overall size of the wheel. as an example

you have a 195/65/15 tire currently then a 185/70/14 would be about as close as you could possibly get to the same circumference. a -0.4% difference.
And if you had a super accurate set of dials in the car that read exactly 10mph at 10mph 20 mph at 20mph and so on.

When the dash reads 70mph, you would actually be doing 69.7mph you can play with that tool and see how it works.

One consideration is that many newer cars cannot go smaller than 14/15 inch wheels because the brakes and calipers are much larger than in the past and the wheels won't fit over the brakes. Diesel cars tend to have bigger brakes, so before down sizing look at the gap between the brake caliper and the inside of the wheel, to make sure there is a big enough gap.

Also Steel wheels are thinner than alloy wheels so if down sizing from steel wheels to alloy, the alloy wheels might not fit where as 14 inch steel wheels would.

Thanking you. . I’ll save that info in case I ever want to do the swop. T.

 

[Herts Hillhopper]

When considering the effect on the speedometer, it’s worth reflecting on how that changes as tyres wear, and helps show why no speedometer on a particular car can always be accurate. A new tyre has 8mm of tread. Worn to the legal minimum it has 1.6. That means a 6.4mm difference in radius, or over 12mm in diameter over the life of the tyre.
Speedometers are not allowed to indicate a ‘lower than actual’ speed, so have to over-read by a degree big enough to cover the differing diameters due to the tyres wearing.
The speed is measured by counting wheel (or gearbox) revolutions. But the distance covered per revolution gets progressively smaller as the tyre’s diameter diminishes, which would show on a GPS speedometer as a lower actual speed than the car’s speedo indicates. I believe the permitted tolerance is ‘plus10%’, although tyres wear would likely alter it by rather less than this.

 

[jrkitching]

although tyres wear would likely alter it by rather less than this

On a 500, the tyre will start its life with a diameter around 580mm (the exact figure will vary by a few mm depending on wheel fitment); by the time it's worn to the legal limit that'll be reduced to around 567mm. That's a difference of 2.25%; at 30 mph, the difference is 0.67 mph. That's well within all the limits and no normal person is ever going to be able to notice any difference in speedo accuracy due to tyre wear.

Inflation pressure will likely have a greater impact on the effective rolling diameter than tyre wear. 500's with TPMS use the difference in rolling diameters between the wheels to trigger the low pressure warning.

 

[PuntoHowTo]

When considering the effect on the speedometer, it’s worth reflecting on how that changes as tyres wear, and helps show why no speedometer on a particular car can always be accurate. A new tyre has 8mm of tread. Worn to the legal minimum it has 1.6. That means a 6.4mm difference in radius, or over 12mm in diameter over the life of the tyre.
Speedometers are not allowed to indicate a ‘lower than actual’ speed, so have to over-read by a degree big enough to cover the differing diameters due to the tyres wearing.
The speed is measured by counting wheel (or gearbox) revolutions. But the distance covered per revolution gets progressively smaller as the tyre’s diameter diminishes, which would show on a GPS speedometer as a lower actual speed than the car’s speedo indicates. I believe the permitted tolerance is ‘plus10%’, although tyres wear would likely alter it by rather less than this.

I dont know the measurement of a say 14inch wheel, but a wheel with a complete overall diameter of say 18inches, the difference on the speedometer is something like 2-3% between fresh tires and worn out tires. If you want to get really pedantic then the tire pressure can have more of an impact.

 

[Herts Hillhopper]

Fair enough

 

[Theydon Mount]

Thanks for all that expert info.

Are 15s better than 14s for long journeys? Motorways etc?