Thinking of changing to a 4x4 next but I like to have a spare wheel in the boot. Bearing mind that the space saver is a smaller wheel will that mess up the differential, I assume that one can not buy a space saver the same size as the normal wheel?

A reduced size spare is ok for what it does. Get you to a tyre centre. The diameter is only reduced in width if I am correct. 4X4 is only used when the surface dictates, less than 1% of the time. Unless of course you have a 280 4X4.

Maybe do not buy a Space Saver, and buy a full size tyre on a steel or allow wheel that Saves Space in allowing the floor to not lift when carried.

As it is the wheel / tyre needs to go in the Spare Tyre Well if on a trip and the boot is full.

 

Emergency Spare Wheels to get you to a place of safety / repair.

Unless the Spare Matches the Tyre / Wheel on the same axle or the other 3, or is the same Directional / or Seasons tyre you need to slow down any way when fitted, 

so Space Saver, Saver of Space or Odd One Out tyre / tread / Compound is what you need to consider.

Or 4 Tyres / Wheels on the car and an identical one as a Spare. Or 2 Spares even.  (Matching Pair for long road trips a log way from Tyre Centres / Holiday / Christmas / New Year in Scotland, 2 days Christmas Closing but 3 or 4 at the 'New Year'.).

15 hours ago, Danny 57 said:

The diameter is only reduced in width

are you sure?

 

https://www.briskoda.net/forums/topic/442912-full-size-spare-wheel/?page=2&tab=comments#comment-5040470

 

20 minutes ago, MartiniB said:

are you sure?

 

https://www.briskoda.net/forums/topic/442912-full-size-spare-wheel/?page=2&tab=comments#comment-5040470

 

 

Doesn't it read very differently   when the obvious is pointed out. I could have said circumference.

Edited 21 November, 20187 yr by Danny 57

I've not seen a full size spare in a car for a while.  My previous Octavia vrs had a smaller diameter spare wheel.  The problem being that if the problem was on the front wheel, you could not fit the spare over the front brakes, so you had to put the spare on the rear and then the rear on the front.

My current superb 280 has a space saver, but the wheel will go over the front.  I

 

In a way space savers are good, compared to full size spares as it means you definitely will get the tyre replaced, instead of possibly leaving it knackered in the boot until it's too late (I've unintentionally had that problem too)

As I understood it the space saver is actually a smaller radius (as well as smaller in width) than the full size wheel, which means it travels a difference distance, That is why the cruise control does not work when you have the space saver on. I will ask my tyre supplier if he can get a spare on a steel rim the same size as the fitted wheel but I suspect it will not go in the space provided for the spare. Why on earth they dont make it big enough is beyond me. With regard to the 4x4 only working some of the time that is true for the rear axle but if the puncture is a front tyre that would mean swopping the punctured wheel (Space saver when changed) on to the rear axle while you got home.

^^^

add to favorites this link

https://tiresize.com/comparison/

 

On 16/04/2018 at 13:34, MartiniB said:

diameter comparison to 215/55r17 and 225/55r17:
205/55r16 _ -5.3% _ -6.7%, this huge size difference cancels usage of cruise control
205/65r16 _ +0.8% _ -0.7%, not tested yet

On a 4x4 the use of the spacesaver spare throws a TPMS warning and will not let you use the cruise control. After a recent incident where we had a tyre basically destroyed while fully laden on the M1 in the 50mph bit, I was very glad I had the spare. Foam would certainly not have helped.

 

The 19" wheel on the car won't fit in the wheel well in the boot so if you really wanted a 'full sized' one then it would need to be a narrower width. I have no idea if it is possible to get a tyre the same diameter but narrower.

 

I can't think that a different size tyre would damage the differential. After all, a differential is designed to allow the wheels to turn at a differential speed   the spare is supplied by the manufacturer so seemingly they have no issues. Anyway, its not like you are going to do lots of miles on the spacesaver unless you like going at 50mph.

 

Be aware that the 19" on the SportLine are an odd tyre size and not commonly available, so finding a replacement quickly might be an issue. When ours let go we were at Northampton on our way to Yorkshire, and the first tyre of that size I found in stock was in Sheffield after about 20 phone calls to places all up the M1. They could all get me one 'for Monday' but on Saturday afternoon with a few 100 miles to go, that wasn't ideal...at least we had the spacesaver so we wern't totally marooned.

On 20/11/2018 at 22:40, Danny 57 said:

A reduced size spare is ok for what it does. Get you to a tyre centre. The diameter is only reduced in width if I am correct. 4X4 is only used when the surface dictates, less than 1% of the time. Unless of course you have a 280 4X4.

Hi Danny,

This is wrong. The Haldex 4 on the old Superb and the Haldex 5 have instant traction. The car's ECU engages 4x4 on starts, acceleration, in cornering conditions and also, as you say, when there is loss of traction.

For the duration hat I'd need to have a space saver on until I get my proper wheel fixed, I'm fine with it.