Dunlop SP2030 tyres - excessive wear on inside edge and cracking between treads

[guest3250]

Would be too far to be worth it unless they actually gave the tyres away 
Nice thought though

[guest3469]

I believe 225/45/17 gives exactly the same rolling diameter at the 175/65/15 tyres.  Has anyone tried going that big or would they snag the inner arches?

[guest3250]

175/65/15 & 185/55/16 aren't even exactly the same - but close
The closest to the 185/55/16 is 205/50/16 - but that is just too wide IMO
I would have had the 175/65/15's if I could have.

17" would require an even LOWER profile and therefor even bumpier ride!
They would only snag the arches if wither the rolling diameter was a lot bugger,
the suspension lwered - or the width was so wide it snagged on tight lock.

[eljuero]

175/65/15 & 185/55/16 aren't even exactly the same - but close

??
They are almost exatcly the same.

[guest3250]

175/65/15 & 185/55/16 aren't even exactly the same - but close

??
They are almost exatcly the same.

Rolling diameter of the Wheel / Tyre combination - the aim is to stay close to the same diameter

Comparing the standard sizes:
15" wheels  175/65/15 
  Sidewall: 4.48 in
  Radius: 11.98 in
  Diameter: 23.96 in
  Circumf: 75.26 in
  Revs/mile: 841.86

  16" Wheels 185/55/16 
  Sidewall: 4.01 in
  Radius: 12.01 in
  Diameter: 24.01 in
  Circumf: 75.44 in
  Revs/mile: 839.92

my suggested
 Alternative 195/55/16 :
  Sidewall: 4.22 in
  Radius: 12.22 in
  Diameter: 24.44 in
  Circumf: 76.80 in
  Revs/mile: 825.04

If we go up in wheel size then we go down in profile to keep the rolling diameter as close
to the same as possible
As I was saying - the 205/50/16 is actually only 1mm larger  than the 185/55/16

With my larger 195/55 suggestion the  small increase won't hurt as the speedo over reads
quite a bit, the slightly larger size will go half way to correcting this...

[eljuero]

If the 175/65/15 is stock, the closest is 185/55/16 (- 0.2%), then 205/50/16 (- 0.5%) and 195/55/16 (- 2%).

And speedo is not correct even with stock 175/65/15.

If I'm not mistaken in my country is allowed up to +- 3% without need to change speedo settings.

[guest3250]

Lost the calculation  - but my 185/55/16 set up over reads by over 4% above 50mph
These wheels/tyres are slightly larger overall diameter than the stock 175/65/15 setup
yet still over reading!
So I am comfortable with using a slightly fatter tyre - the online calculator tells me I will have a 1.8% increase over the 185/55/16 - so I make it that I will still be slightly over reading and therefor at speedo 70mph I will still be under 70mph actual. (but more close to accurate)

My insurance company posativly endorsed the idea - they seemed to think that a fatter tyre is always a better tyre!!! 
While I will benefit from paying less for a given tyre (about 5%) and also have much more choice available - that is really NOT my reason for considering a fatter tyre. Ultimately there has to be a little more rolling and wind resistance,  and on very wet roads there is a slight increase in the possibility of aquaplaning - so I will try to choose carefully balancing the advantage of cheaper options against wet (primarily) perfomance.
It will make the ride very slightly more comfortable and at the end of the day the increase is very small
so it shouldn't make cornering spongy for that small a difference.
Next month I will be buying - so I will report back posative or negative results and observations.
 

[guest3250]

Update:
New 195 tyres ordered - will report on how it feels / drives after I have tried them for a while.

[guest3250]

Anyone considering doing this - changing the expensive 185/55/16 tyres to 195/55/16 I would say
DO IT!!
Visibly the difference is tiny
Even in the freezing weather I can just detect there is a slightly softer thump going over speed bumps.
Handling (discussions about the merits of various differnet brands aside) is completly fine - in fact I reckon the car feels a little better all round -and I have opnly changed the fronts at the moment!
The ride is a little less jittery and yet the handling is not compromised. It is winter and freezing - and I am only driving around town - I will have to wait to see if there is any percievable change in fuel economy - but I did purchase a tyre with a good rolling resitance rating so it should also be fine.

[Defender]

I have a set of those so I'll give that a try, I want a bit more weight to the steering as it still feels too light and that might well do it .

[guest3250]

I have a set of those so I'll give that a try, I want a bit more weight to the steering as it still feels too light and that might well do it .

The weight on the steering will most likely be more affected by the Tyre make and the tyre pressure.
The 185/55/16 is supposed to be 32lbs/²inch I put the same in my 195/55/16's
So it depends if you have a tyre preference I guess
Having said that - I feel the steering 'feels' nicer, so it could be that it is a little heavier

[olduser1]

Great to hear of your success in changing EX tyres.

[guest3250]

Frustrating that I have 2, nearly new, non matching 185's on the back!!
Will pop them on the front in the Summer and leave them there untill they are
finished, now that I am happy with the 195's

[DV]

I`m well behind you guys with 16" 195 tyres... I`ve 14" 175/65 and considering to fit 185/60 next year 14".
Good to hear 195 works well.

[Defender]

That's what I'm looking for basically, more feedback, it's not remote or vague like some cars, just not 'weighted' quite enough for my liking .
BTW, on a cautionary note, I think having wider (195) tyres on the front and narrower (185) tyres on the rear is a contravention of Construction and Use rules?, the other way round is fine, it dates back to when all vehicles were RWD .