Upgraded my 2012 FIT Sport with 205-50-18 YK-580s. Result was a marked improvement at highway speeds; 60-75MPH. YK's are quieter than the OEM Dunnies.

H/W MPG average appears same as before but city MPG average has decreased a bit.

Suggestions for other handling improvements would be welcome.

 

its probably a good idea to keep within stock diameter. 18's are a bit big, especially with those tires. this may help http://www.rimsntires.com/specs.jspa

 

Big typo error when I entered tire size. My YK580s are 205-50-16.

 

I actually did the same upgrade two weeks after I bought my 2013 fit and it was one of the best upgrades I have done. Handling, gas mileage, ride quality and many other attributes have been impacted greatly. All are much better now. I am trying to not upgrade the fit so I do not have to deal with warranty issues if anything was to ever happen but it is difficult not to want to. Good tires but I could use a wider wheel.

 

interesting, i saw a consistent 1-2 mpg drop in my mileage when i put these on as replacements for the OEM Dunlops... im running the same size too, 205/50-16... agree they are a great tire, i'll probably buy again if they're still available when this set goes... they're rated at 60k but i doubt i'll get that out of them... currently have about 34k now, and im hoping they make it to 50k

 

With these tires on the car and I drive about 80/20% hgwy/city, I see an average of about 38-42mpg. Better than the stock dunlops.