V50 17" Serapis to 18" Medusa

[Cheesa]

Hi all, I was hoping for a little advice please.

I have a V50 Rdesign which currently has 17 inch Serapis alloys fitted.

I'd like to change these to 18 inch Medusa alloys and having read various posts as I understand it the recommended tyres for these are expensive (215/45).

I've seen many posts recommending to instead use 225/40 tyres as these are cheaper and these are what I am leaning towards.

My question is, if I switch from 17 inch alloys with 205/50 tyres to 18 inch with 225/40 tyres do I need to get the speedo updated? Are there any other considerations?

Thanks in anticipation!

[domhart10]

Should be fine, I have changed my wheels over on my car and speedo is fine.

Different variations

215/45 on my 17s which was for a winter tire
225/45 on my 17's again but for a summer tire

My car originall had 18's on but swapped them out for 235/40 all round.

[RollingThunder]

I'm always faffing about with non standard tyres lol. Put the current/proposed tyre size details into this webpage and make sure the overall diameter is roughly the same - within 5% is usually ok, I try and get upto 5% larger rather than smaller.

https://www.tyresave.co.uk/tyre-size-calculator/

You have to be careful that the extra width of the tyres won't be a problem (rubbing on suspension components, wheel arches etc). Its usually only a problem if you go much wider, but its still worth bearing in mind.

Having said that, I stuck with the standard size this time around as I think the ride comfort/handling balance is about right on the S40 std fitment.

HTH