Can I replace 215/55 R16 tyres with 225/55R16

CDTi · 9th January 2009, 18:40

As per the title.

Will the 225s fit the same rim?

I think the wider tyres should look better, give more grip but probably use a bit more fuel.

Any opinions?

P.S. apologies for all my tyre queries

T-Cut · 9th January 2009, 19:18

A few thoughts.
The handbook only indicates 225mm tyres fitted to 7.5J rims, not the 7J used for the 215mm ones. They may well be OK, but its non-standard. Advice needed.
Do 225mm look better than 215mm? It's a personal thing.
Will they give more grip? I doubt it actually. Increasing the width will reduce the contact pressure, so it may be swings and roundabouts. Advice needed.
Will they use more fuel? I've no idea, but it doesn't seem very useful. The rolling diameter is longer so there'll be some implication on speedo etc accuracy. It's likely to be OK, but best check this for legal reasons.

You can probably do it without any problems, but why would you want to? Are your standard tyres not coming up to expectations? Would a brand change rather than a size change be better?

TC

Jules · 9th January 2009, 19:31

Wider tyres on the same rim won't necessarily grip better, instead the tyre wall will "flex" more round corners IMO

afcbadam · 9th January 2009, 19:52

Quote:

Originally Posted by Jules

Wider tyres on the same rim won't necessarily grip better, instead the tyre wall will "flex" more round corners IMO

agreed. i would have thought to be quite dangerous

CDTi · 9th January 2009, 19:59

Thanks for the input guys.

I think I'll be sticking with the recommended size.

Samuelle · 9th January 2009, 20:08

Back in my motorcycle courier days I sometimes used to put oversize part worn tyres on my cbr600 or vfr750, when it was all that I could get. They could be hard work getting on and off, would pull the tyre out of it's correct profile, and were certainly never an improvement over standard sizes.

Will they clear the wheel arch? Don't forget they will be higher as well as wider, as the 55 is a proportion of the 225, rather than a measurement itself. I certainly wouldn't pay a few quid extra just to get a tyre that doesn't fit the wheel correctly.

JohnDotCom · 9th January 2009, 20:22

It is also meant to be the tyre wheel combination size as fitted or available by manufacturer for Insurance purposes.
An easy way for a non payout scenario.

EXMSRalph · 10th January 2009, 12:25

The speedo will also be affected, since you will have a larger rolling circumference. Thee 55 in the tyre size is the depth of the side wall as a percentage of the tyre width, so you will have a large diameter tyre.

James.uk · 10th January 2009, 12:50

This will answer most of your tyre questions. And it's simple to use.

http://www.miata.net/garage/tirecalc.html
.

CDTi · 10th January 2009, 18:05

Thanks for all the help, lads, but I have now ordered the standard size tyres.

9th January 2009, 18:40	#1
CDTi This is my second home No longer in the MGR club Join Date: Nov 2006 Location: Tipperary Posts: 3,933 Thanks: 35 Thanked 51 Times in 35 Posts	Can I replace 215/55 R16 tyres with 225/55R16 As per the title. Will the 225s fit the same rim? I think the wider tyres should look better, give more grip but probably use a bit more fuel. Any opinions? P.S. apologies for all my tyre queries __________________ 'Tis better to be silent and be thought a fool, than to speak and remove all doubt.

9th January 2009, 19:31	#3
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Wider tyres on the same rim won't necessarily grip better, instead the tyre wall will "flex" more round corners IMO __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

9th January 2009, 19:59	#5
CDTi This is my second home No longer in the MGR club Join Date: Nov 2006 Location: Tipperary Posts: 3,933 Thanks: 35 Thanked 51 Times in 35 Posts	Thanks for the input guys. I think I'll be sticking with the recommended size. __________________ 'Tis better to be silent and be thought a fool, than to speak and remove all doubt.

10th January 2009, 18:05	#10
CDTi This is my second home No longer in the MGR club Join Date: Nov 2006 Location: Tipperary Posts: 3,933 Thanks: 35 Thanked 51 Times in 35 Posts	Thanks for all the help, lads, but I have now ordered the standard size tyres. __________________ 'Tis better to be silent and be thought a fool, than to speak and remove all doubt.

9th January 2009, 19:18	#2
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,753 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	A few thoughts. The handbook only indicates 225mm tyres fitted to 7.5J rims, not the 7J used for the 215mm ones. They may well be OK, but its non-standard. Advice needed. Do 225mm look better than 215mm? It's a personal thing. Will they give more grip? I doubt it actually. Increasing the width will reduce the contact pressure, so it may be swings and roundabouts. Advice needed. Will they use more fuel? I've no idea, but it doesn't seem very useful. The rolling diameter is longer so there'll be some implication on speedo etc accuracy. It's likely to be OK, but best check this for legal reasons. You can probably do it without any problems, but why would you want to? Are your standard tyres not coming up to expectations? Would a brand change rather than a size change be better? TC

9th January 2009, 20:08	#6
Samuelle Regular poster MG ZT CDTI 135+ Join Date: Jul 2008 Location: Sussex Posts: 84 Thanks: 8 Thanked 0 Times in 0 Posts	Back in my motorcycle courier days I sometimes used to put oversize part worn tyres on my cbr600 or vfr750, when it was all that I could get. They could be hard work getting on and off, would pull the tyre out of it's correct profile, and were certainly never an improvement over standard sizes. Will they clear the wheel arch? Don't forget they will be higher as well as wider, as the 55 is a proportion of the 225, rather than a measurement itself. I certainly wouldn't pay a few quid extra just to get a tyre that doesn't fit the wheel correctly.

9th January 2009, 20:22	#7
JohnDotCom * Rover 75 FaceLift Tourer CDTi 170BHP Auto ConnSE 2005 Model Starlight Silver Join Date: Nov 2006 Location: Abergele Posts: 28,735 Thanks: 0 Thanked 6 Times in 5 Posts	It is also meant to be the tyre wheel combination size as fitted or available by manufacturer for Insurance purposes. An easy way for a non payout scenario.

10th January 2009, 12:25	#8
EXMSRalph Gets stuck in ZS180, MGF, Rover 400, MG Montego Join Date: Sep 2007 Location: Sittingbourne Posts: 534 Thanks: 0 Thanked 0 Times in 0 Posts	The speedo will also be affected, since you will have a larger rolling circumference. Thee 55 in the tyre size is the depth of the side wall as a percentage of the tyre width, so you will have a large diameter tyre.

10th January 2009, 12:50	#9
James.uk Passed Away 2002 Pale Blue. Rover 75 CDTi Connoisseur auto. 170K miles Join Date: Dec 2008 Location: Near the M67. Posts: 14,509 Thanks: 199 Thanked 585 Times in 397 Posts	This will answer most of your tyre questions. And it's simple to use. http://www.miata.net/garage/tirecalc.html .