Tyre width question

[Jon Doe]

I have heard of oversizing the width of tyre that should be used. So for instance, my specific question is this-
Can I fit a 205 width tyre to a 195 size wheel. Would this give me some benefit or is there a train of thought saying dont do it.

Also, if you have some reasoning as to why or why not then let me know. Obviously, there would have to be the clearance with suspension, but apart from this is it ok?

[LaurenceFrost]

Most performance tyres list their minimum, optimum, and maximum rim width. A 205 in one make will have different rim requirements from another.

The best thing to do is look up the tyres with the manufacturer and see which rim sizes they will fit.

Typically a 205 tyre will fit on anything from a 6 to a 7.5 inch rim for example, so you have room for movement.

There is no major advantage to fitting a wider tyre though unless you are overheating the ones you have.

[jon-]

Tyre width to rim width is largely effected by the tyre profile. For instance a 205/25 would have a much smaller rim window than a 205/65.

Toyo list tyre sizes to rim width on their site, it's a good read.