Been trawling through web site's after some cheap Toyo T1R's, but when looking i've found that some site's advertised 225/45ZR17 94Y RF and other's 225/45R17 94Y. Now I have the 225/45ZR17 94Y RF on the rear and would like the same on the front. Are they just different speed rating's of the same tyre or just advertised differently. Also about £30 cheaper per tyre for the non ZR ones????

All advice thanked in advance.

Using the example of a tyre marked : 225/45R17 94Y

225 : the tyre width is 225 mm,

45 : the sidewall represents 45% of the width of the tyre,

R : the tyre is of Radial construction,

17 : the internal diameter of the tyre is 17 inches,

94 : the load rating is 94 which corresponds to 670 kilograms,

y : the y performance symbol corresponds to a speed of 186 mph

Chekc this out

Tyre Sidewall Explained

Some say that the Z in one of your examples refers to the performance rating there seems to be varying opinions. Most support above. It could be just the Japanese or European notation being slightly different.

I would say that there will be little difference and you would be fine as long as you use the above information

:iagree: - what bothers me slightly is the RF, which appears to indicate a re-enforced sidewall Winter tyre?

:iagree: - what bothers me slightly is the RF, which appears to indicate a re-enforced sidewall Winter tyre?

RF is Run Flat on Pirellis - don't know about other brands?

In which case, ISTR RFs (not Toyos; I wasn't aware of a runflat Toyo) being implicated in poor ride on broken surfaces due to the very stiff sidewalls.