Traditionally, with alloy rims, the spare tyre was on a steel rim because (a) it was cheaper (b) mostly was not seen (c) it was a temporary fix until the alloy was repaired.
It is easy and cheaper to buy a 175/65 R15 84H steel rim and tyre set as a spare. I am pretty certain that this is what Honda would have supplied in the days when they supplied a full size spare (others might correct me).
A 16” rim with a 185/55 R16 tyre is the same diameter on the road as a 15” rim with 175/65 R15 and is the same rolling circumference.
Both the 185/55 R16 and the 175/65 R15 have an overall diameter (rim and tyre) of about 24”. The additional height of the wall on the 65 on the 15” wheel compensates for the lower wall 55 on the 16” wheel – so the two are virtually identical in overall dimensions as far as overall diameter is concerned.
The 16” is wider and looks more dashing. The 15” is narrower. This difference is shown above by the 185(mm) (wider) for the 16” and 175(mm) (narrower) for the 15”. This is not a problem for emergency temporary use and, I would suggest, is much better than you would get with the space saver. Of course, there will different wheels on the car and you should drive with caution.
Try:
http://www.mytyres.co.uk/Complete_wheels.htmlMy impression is that, with any spare not fitted with TPMS, the TPMS warning light will come/ remain on until the original wheel set is reinstalled. This seems logical and is a factor of having a emergency temporary wheel set fitted and the indicator is telling you to do something about it.
Hope this helps,
Others may have other thoughts,
For some reason it seems rims are measured in inches and tyres are measured in metric!