What speed rating of tyre for Griff 500

[FFMan]

the current tyres are z rated. This table would suggest that a W rating is fine as well:-

http://www.blackcircles.com/general/speedrating

What do people recommend - the Toyo seems to be highly rated on this forum.

[900T-R]

This is correct - 'ZR' is the old catch-all for any tyre with a 240 km/h (149 mph)+ speed rating, covering the later 'W'(270 km/h) and Y (300 km/h) categories. For this reason one can see tyres designated as '225/55ZR16 W' for instance.

[JR]

900T-R said:

This is correct - 'ZR' is the old catch-all for any tyre with a 240 km/h (149 mph)+ speed rating, covering the later 'W'(270 km/h) and Y (300 km/h) categories. For this reason one can see tyres designated as '225/55ZR16 W' for instance.

Just to clarify, W and Y are sub categories of Z that did not exist when the Griff was designed.