[SNJ]

Two newbie questions so sorry if they're are naive ones!

Are there are any disadvantages whilst driving or parking to having 17" wheels rather than 16" ones or 15" ones? Is bigger better, in terms of wheels?

My second question is about run flats - why do most people dislike them? Are they really that bad in terms of ride and noise?

I'm looking to buy a Mini and these two wheel questions are in my mind - no point asking a salesman!

Thanks very much!

S

[CC07ERS]

runflats are stinking dear not recomended to get repaired if you get punture

[bigcoyote]

Hey there,

Wheel size effects how well the car handles - a larger wheel ( 17" ) handles better than a small wheel ( 15" ), But a small wheel gives a softer ride. What is more important to you in your dailey driving - better cornering or softer ride????
Also tires for 15" wheels are less expensive then tires for 17" wheels.

As far as the runflats go... I have a set of Pirrelli Euphoria 17" runflats and I like them - they are a "summer only" tire but here in the Arizona Desert it is summer all year round . The run flats are very expensive and you can buy non-run flat tires for alot less $$.

Good luck

[Paul]

Quote: Originally Posted by bigcoyote

Wheel size effects how well the car handles - a larger wheel ( 17" ) handles better than a small wheel ( 15" ), But a small wheel gives a softer ride.

That's very simplified, and I would argue not true in the case of the MINI. Maybe by handling you mean grip, but that's more to do with the width and tread pattern than it is dimension.

It really does depend how and where you drive as to what's ideal, that's why you'll see very different wheel/tyre decisions made in different racing conditions and diciplines. It's trye that a smaller wheel compared to the larger will generally give a "softer" ride, you could also say the ride is more progressive.

There's considerations such as the unsprung weight (VERY important) the rolling radius, the contact patch with the road, the sidewall flex.....

Runflats are generally disliked because they're a bit (well very) stiff in the sidewalls, which means very little flex and a fairly unforgiving ride. The runflat range on offer also isn't great in terms of grip etc when compared to performance tyre options, which often cost less.

[Tonyt3]

As an example between runflats and non-runflats in terms of comfort....

I sufferred from a bad back when I had 17" runflats on my car, and the discomfort was so bad I ended up running them at a lower pressure than recommended to help. The bad back wasnt caused by the runflats, but the car was so 'bouncy' with them that it actually made it worse......

when I changed to non runflats, not only did it help my bad back by not being so jarring a ride, but it actualy made the car substantially quicker, especially on bumpy, cambered B road driving.


Runflats are fine for long motorway journeys, but for spirited back road driving, proper tyres out perform them. However, perhaps they have improved substantially since the three years that have passed since I had some...?

[SNJ]

Thanks for all the advice!

[deggles]

Quote: Originally Posted by SNJ

Are there are any disadvantages whilst driving or parking to having 17" wheels rather than 16" ones or 15" ones? Is bigger better, in terms of wheels?

Just to go back to your original question - one thing to bear in mind is that 17"s with low profile tyres are much easier to damage on kerbs and potholes compared to say, 15"s on standard tyres. Worth remembering when parking and driving around town.

I was reminded of this yesterday as I tried to get out of the way of a rather impatient oncoming bus - had to scrape the kerb to avoid gaining a bus-shaped scratch down my off-side

The 17"s do look much better though

[Richard Crofts]

Runflats make the cars ride quite harsh (bumpy and jarring) they also lack the grip of other types of tyre so seem to slide more and dont perform that well in the wet (IMHO). They also wear very very fast...I had 2 sets since 2003 and in both instances they have been terible for wear with my Coopers tyres doing about 8000-10000 miles and the S ones doing about the same. I have done 6000 miles on my Toyo non runflats and they still have yet to show significant wear.

Regarding wheels. Bigger is better in terms of looks IMO. However with regard to handling the smaller and wider the better. Eg. a 15" rim with an 8" width (sports wheel) and a good tyre will handle the corners etc better than a 18" rim with the same width and tyre. The bigger the rim the worse the handling in corners. Also as the rim size increases the lower the profile (height) of the tyre has to get to keep accurate speedo readings. The lower the profile the harsher and twitchier the ride becomes....17" with a 45 profile is the best compromise. I run 18" with 35 profile and although very grippy (tyre wise as its not a run flat) it doesn't handle as well and is far twitchier than my BMW 17" with a 45 profile without runflats.

[SNJ]

Thanks very much for the last two replies - that's really helpful to me.

Thanks Richard for explaining about the wheels - I will probably go for a 16" wheel as a compromise....maybe 205/ 50 - 16. Not sure which make of tyre as there are so many to choose from!

I haven't got a Mini yet but might look for one that has had its tyres replaced with Non RF ones.

[minigolf]

I took the time to go back a couple of pages to find some similar threads. Remarkably these questions are quite common and it doesn't take much time to find a similar thread.

How does wheel size affect handling?

New tyres?

Which tyres to replace my runflats

Other than that there's been some pretty solid replies in here so far.

[lionhearts]

What's the widest tires and wheels the MINI can take? If wider than 8 is there a benefit to anything wider than this?

[TimCrighton]

Not particularly - other than you will be producing more pure mechanical grip, via tyre to road contact patch. Again as mentioned above fitting wider rims typically increases the 'unsprung' weight (the weight of the car not supported by the suspension when on the ground) and this can be detrimental to handling. That said there are reasons you would choose to run larger/wider wheels, this could be due to brake clearance, chassis clearance, indeed it is possible that the roll centres of the car have been designed for a larger rim (in the case of say a Noble or a TVR) and low tyre profile. You can physically over grip a car, producing so much mechanical grip that the car bogs down in the cars and won't release quickly enough, although this is usually restricted to race cars and not road cars and so sometimes it advisable not to go wider. Other issues to consider for road use are that increasing the wheel width also increases the likelyhood of the car to 'track' on the road and follow the camber which can prove fustrating especially on motorway driving.

Further effects of changing the wheel tyre combination are that you effectively alter the spring rate by doing it. Reducing the tyre profile, and the side wall stiffness changes the 'effective' spring rate and can impact handling a lot, this is one of the factors that makes run flats so unpopular (combined with the price and the lack of compound choices available!). Going for a smaller rim allows you to adjust the effect spring rate more, and this is usually done via tyre pressure, although there are other factors in tyre pressure, but you can run softer pressures to effectively reduce the spring rate on the car. This is one of the reasons that track cars generally run a higher tyre profile than a road car as the suspension is easier to adjust and fine tune.

I hope that makes some sense - Its a little difficult to describe! Its one of a lot of variables used in the set up of a car but it can make a big difference.

[sjrainsford]

Don't forget another simple thing, not yet mentioned.

Yes wider tyres do generally handle better.

But in the wet it's the opposite story. Generally wider tyres aren't as good. Not always I must say, but generally.

It's all about your preferences at the end of the day. Wheel size is more about looks, choose what you think suits the car. Tyre type and width again is preference, getting your favourable compromise between good handling, good ride and price.

[Black&Blue]

hi ive got 18inch JCW wheels and they say i cannot have normal non-runflats, this has not come from bmw dont know if this is true.
i no you can get non runflats on 17'' not sure about 18''.
thanks mark

[Black&Blue]

?

[JG.26]

One day I might try non run flats on my S spokes. I don't dislike the run flats, it's how you look at it, I feel safer driving with run flats than I probably would do with standard tyres, I guess it's what you value in your drive, better grip and better ride with standard tyres verses high speed punctures and safety and the thought of driving in the middle of nowhere at night and getting a puncture and still being able to drive on. Thing to bear in mind is runflat technology is ongoing and improving and most new cars will have runflats over the coming years. Personally I think they are a good thing albeight expensive at the moment

[mini_macky]

i'm rolling on Volk TE37s with Advan AD07 tires. rides great, handles even better, & did i mention they're light as a feather?

one thing you have to do when you get aftermarket 15s: get a set of lowering springs. my Mini simply looked silly on stock springs when i first got the rims

[herbie hind]

Quote: Originally Posted by bigcoyote (original)

Hey there,

Wheel size effects how well the car handles - a larger wheel ( 17" ) handles better than a small wheel ( 15" ), But a small wheel gives a softer ride. What is more important to you in your dailey driving - better cornering or softer ride????
Also tires for 15" wheels are less expensive then tires for 17" wheels.

As far as the runflats go... I have a set of Pirrelli Euphoria 17" runflats and I like them - they are a "summer only" tire but here in the Arizona Desert it is summer all year round . The run flats are very expensive and you can buy non-run flat tires for alot less $$.

Good luck

i disagree ; a smaller wheel will always handle better than a big one . the gyro effect of a large wheel on direction change is greater than that of a smaller wheel . turn in is far better with a smaller wheel . this is why most auto x'ers use 16 and 15 : also why honda motorcycles in the 80's went to 16"front tires for a cheap way to quicken steering responce rather than change head angles and such. i went to 16's from 17's and was amazed . no more push .

[BlackEyedPea]

i recently bought a set of EAGLE RS-A EMT 205/50 R17 93V XL runflats with RS-3 multispoke 17x7 alloys. havent fitted them as yet, but will soon see all the fuss is about. at the mo i have 16" Fin spoke alloys and they feel fine....a little rough on speed humps but great on the highway.

[Black&Blue]

any one want to answer my question?
ive got 18inch JCW wheels and they say i cannot have normal non-runflats, this has not come from bmw dont know if this is true.
i no you can get non runflats on 17'' not sure about 18''.
thanks mark