15 or 16 inch wheels for ride comfort?

[AJP]

Hi all. Thinking of trading in my ten year old Octavia for a new Fabia estate. I am considering the SE, SEL or even Monte Carlo versions with manual gearbox and 110ps engine. I haven’t seen any particular comments on ride comfort so would I be “safe” with either the 15 or 16 inch wheels? Not sure if I will be able to test drive both before finally choosing. Any pointers please.

Thanks

[SurreyJohn]

In general the smaller the rim, and deeper tyre sidewall the softer the ride will be.  The outside circumference will be virtually identical so it not like you get smaller wheels with smaller rims (but tyre width may be different).

 

The latest cars come with Eco summer tyres (officially low rolling resistance summer tyres), these are very firm, and below about +10c are hard and grip poorly.   Changing to an all season tyre, or fitting winter wheels and tyres will make ride lot more comfortable from November until March (until April if you are in North) as these are lot more compliant below about +12c

 

EDIT : Just checked and brochure says 15 inch has low rolling resistance tyres, 16 inch has (normal summer) tyres.  The 16inch is more obscure tyre size (and possibly low rolling resistance not yet made in that size).

 

 This means which is best will be different on cold day to a warm day, which rather complicates your question. Buying the 15 inch gives better/cheaper choice of all season tyre, but go for 16s if you get winter wheel set.  Tyres will cost lot more in the rarer 215/45 R16 86H size

 

Edited 7 March, 2021 by SurreyJohn

[AJP]

Thanks for the info. 

[Carlston]

215/45R16 are fitted to 7Jx16 ET46 rims.

 

Because 215 tyres are very wide, the rims have to use a lot of offset so that the tyres don't stick out past the edge of the wheelarch, which reduces the front and rear track, ie. the distance between the centre of the left tyre and the centre of the right tyre is reduced.

 

Non-standard 195/50R16 tyres could be fitted to 6Jx16 ET35 rims which would increase the front and rear track by 22mm, compared to ET46 rims

 

However, 16" wheels on the Fabia make no sense. Both 195/50R16 and 215/45R16 are not common sizes and far more expensive than alternative 15" sizes.

 

Compared with 16" tyres, 15" tyres are more comfortable on the Fabia due to increased sidewall height.

 

185/60R15 tyres fitted to 6Jx15 ET38 rims is a good place to start on the Fabia MK3.

 

According to the Skoda configurator, it looks like you can only order the 110HP Fabia with 16" or 17" wheels. It makes sense not to include a 14" tyre option with the 110HP model, but to not include a 15" option doesn't make sense, especially as the 16" tyre option is for too wide 215/45R16 and not the more sensible 195/50R16 width. Compared to 185/60R15, there's a signification increase in fuel consumption when using 215/45R16 tyres.

 

Edited 8 March, 2021 by Carlston

[AJP]

Thanks. I think I will be opting for the SE model with 15 inch alloys. I have drawn up a spec from the Skoda UK web site which allows these with the 1.0 tSI 110 ps engine. Going to check availability later as there is a note that “this engine is only available from stock. Check availability with dealer”. I hope I can get this as I would prefer the extra power and, funnily enough, this engine 0-60 time is the same as quoted for my existing 1.4 tsi Octavia.
I appreciated your time taken to offer this response.

[rum4mo]

@Carlston The best part of the "it makes sense not to include a 14" tyre option with the 110PS model" stems from the size of the front brakes.

[HeavyMetalRich]

I was told two weeks ago that there was no 110hp models available new. So existing stock is your best chance. 

 

I ran 16" wheels on our hatch for a few months and didn't notice any real difference in the level of comfort. I was running 205/50R16 on wheels off a Mk1 Octavia vRS, the rolling circumference equated to be the closest to that of the 185/60R15s on the car originally than anything else.

[AJP]

Thanks. Yes. No more available but My local dealer managed to find me one. Very low mileage SE 110 with 15 inch alloys. I have Continental All Seasons Contact tyres on my Octavia and they are brilliant in all weathers, in my view. I will maybe change to them later in the year depending on how I get on with the currently fitted ones. I doubt comfort will be an issue (16 inch MAY have been - hence my initial enquiry)  but the extra sure footedness in snowy conditions was well worth the switch to Continental.

Your reply was much appreciated.

[SurreyJohn]

3 hours ago, AJP said:

Thanks. Yes. No more available but My local dealer managed to find me one. Very low mileage SE 110 with 15 inch alloys. I have Continental All Seasons Contact tyres on my Octavia and they are brilliant in all weathers, in my view. I will maybe change to them later in the year depending on how I get on with the currently fitted ones. I doubt comfort will be an issue (16 inch MAY have been - hence my initial enquiry)  but the extra sure footedness in snowy conditions was well worth the switch to Continental.

Your reply was much appreciated.

Good result

 

Its March now, so the original summer tyres will be fine until weather gets cold again in November, but I would put a note on your calendar to order the all seasons late Aug or early Sept (as prices always rise in Autumn).  Continental all season contact is one of the best all season tyres.

 

 

[Carlston]

8 hours ago, rum4mo said:

@Carlston The best part of the "it makes sense not to include a 14" tyre option with the 110PS model" stems from the size of the front brakes.

 

It's not just that 14" wheels won't fit over the front brake calipers on the 110PS engined models, but 175/70R14 doesn't really have the performance to match the power of the engine. The tyre manufacturers tend to agree, because most of them don't make tyres in that size with a speed rating above 118mph.

 

Edited 8 March, 2021 by Carlston

[Carlston]

6 hours ago, HeavyMetalRich said:

I was told two weeks ago that there was no 110hp models available new. So existing stock is your best chance. 

 

I ran 16" wheels on our hatch for a few months and didn't notice any real difference in the level of comfort. I was running 205/50R16 on wheels off a Mk1 Octavia vRS, the rolling circumference equated to be the closest to that of the 185/60R15s on the car originally than anything else.

 

205/50R16 on 6.5J rims will ride more comfortably than 215/45R16 on 7J rims.

 

205/50R16 is oversize for the Fabia, so the comfort comparison would be better against oversize 15" tyres such as 195/60R15 on 5.5J or 6J rims.

 

205/50R16 doesn't even have as high a load index as 195/60R15...87 (545kg) versus 88 (560kg). So the 15" tyre wins again.

 

Edited 8 March, 2021 by Carlston

[Ootohere]

The assumptions of different sizes that "will ride more comfortably."  is nonsense really.  Very much a generalisation.

As people might find when driving different cars on the different tyre / wheel sizes.

They may do but it depends on the actual car, the suspension it has, the load in the car, passengers and things, and the tyre pressures and what someone considers as 'More Comfortable'.

There are reasons that not all buy the cheaper cars with narrower tyres that feel like they are on a 'Magic Flying Carpet'. 

[AGFalco]

You will also find some tyre manufactures have a thicker / stiffer side wall compared to other manufactures in the same size.

Then some manufacture of tyres make different thickness / stiffness of side wall in the same size.

 

Pirelli only make 3700 different types of passenger tyres.

You can find that they can have as many a 20 different tyres in one size. 

 

Thanks, AG Falco

Edited 9 March, 2021 by AGFalco
of not if typed

[Carlston]

14 hours ago, e-Roottoot said:

The assumptions of different sizes that "will ride more comfortably."  is nonsense really.  Very much a generalisation.

 

You're only saying that because you don't understand the maths and physics behind what makes one tyre size more comfortable than another. If I wasn't sure about one tyre size being more comfortable than another tyre size I wouldn't say it.

 

Here are two groups of tyres with the comfort level gradually getting worse from left to right.

 

Load index 84 (500kg)

175/70R14, 185/60R15, 195/50R16

 

Load index 91 (615kg)

195/65R15, 205/55R16, 225/45R17

 

As you move from left to right in the two groups above, the contact area between the tyre and the road stays the same. This is because in each group the load index stays the same and therefore the tyre pressure stays the same. However, as you move from left to right in the two groups above, the shape of the contact patch changes.

 

Do you know how the shaped of the contact patch changes? The answer to this question is fundamental in understanding what makes one tyre size more comfortable than another.

 

Edited 9 March, 2021 by Carlston

[Carlston]

21 minutes ago, AGFalco said:

You will also find some tyre manufactures have a thicker / stiffer side wall compared to other manufactures in the same size.

Then some manufacture of tyres make different thickness / stiffness of side wall in the same size.

 

Sidewall construction is another variable.

 

Other variables includes tyre pressure and rim width.

 

To maximise comfort from a tyre you optimise all four variables.

 

Edited 9 March, 2021 by Carlston

[Ootohere]

@Carlston I only say it because for the past 5 decades i have driven many cars & vehicles of all types with many wheel and tyre sizes and have had cars i kept for many years and that got many different tyres fitted over the years or changed during the seasons.

My tyre buying over the years for many cars leads me to believe i have some idea about the actual comfort difference tyres can make, 

and the difference to the handling and economy.

 

Maybe eventually you will tell us what car you drive and what tyres you fit to the cars you drive.

 

 

 

 

Edited 9 March, 2021 by e-Roottoot

[AGFalco]

1 hour ago, Carlston said:

Other variables includes

and mass.

 

Thanks, AG Falco

[bongobob]

I found running 6j x 15 wheels with 185/60 r 15 tyres to be very comfortable and increased mpg. Although the increased mpg may have had something to do with the forged Audi Pepperpots. 

[Ootohere]

More likely how narrow the tyres are.

[bongobob]

The Audi Pepperpots are forged, not cast, so they’re very lightweight, but yes, narrower tyres do improve mpg.

Edited 29 May, 2021 by bongobob
Typo

[Ootohere]

We all know about unsprung weight but 'the wheels on the bus go round and round.'#.   so light wheels on the flat and going up hills.   Heavier wheels might help you down hill or coasting on the flat.     Put passengers in the car and there is more sprung weight.     EV,s now have Aero wheels and it is dead easy to check the difference in range so the same as Economy if it was an ICE when you change tyre types and widths.

Edited 29 May, 2021 by e-Roottoot

[Ootohere]

PS, I think you meant 'decreaded MPG.'.  Doh my bad.  Yes you got more miles per litre.  So increased the mpg.  If the tyre circumference was the same and you were accurately getting the distance covered.

Edited 29 May, 2021 by e-Roottoot

[Carlston]

5 hours ago, bongobob said:

The Audi Pepperpots are forged, not cast, so they’re very lightweight, but yes, narrower tyres do improve mpg.

 

6Jx15 ET38 Pepperpots weigh about 5.5kg each without the tyres. They are amazingly light. According to "eshop skoda cz", standard 6Jx15 ET38 alloy rims on the Fabia MK3 are between 7.5kg and 8.8kg. So normal rims add between 8kg and 13.2kg to the weight of the car.

 

Even the lightest 7.5kg Fabia MK3 alloy rims will add 8kg to the weight of the car, and this is revolving weight which affects acceleration more than just adding 8kg to the non-rotating weight of the car.

 

Let's say the standard Fabia MK3 does 0-60mph in 10 seconds on the lightest standard 7.5kg alloy rims. Changing to 5.5kg Pepperpots could knock that 0-60mph time down to about 9.9 seconds, ie. almost a 1% improvement in acceleration.

 

However, running 185/60R15 tyres rather than 215/45R16 tyres, will make a much bigger improvement to the fuel consumption than the change to lightweight rims. Perhaps a 3% improvement from the change in tyre size and 0.5% improvement from the change in rim weight.

 

Edited 29 May, 2021 by Carlston

[Ootohere]

We will assume there is good grip with a dry surface and those narrow tyre grip and go and maybe just maybe the acceleration time will better that on the wider tyres.

[logiclee]

The OP is looking for optimum ride quality and considering SE, SEL or Monte Carlo.

 

Surely the biggest issue here is the sports suspension on the Monte. Makes the ride much firmer around town.