View Full Version : for the record.... rta tyre max

22-08-2003, 01:49 PM
spoke to the rta tech centre,
you are allowed 1 inch wider, and 15mm tyre and rim combined higher than the maximum on your manufacturers tyre plaquard.

23-08-2003, 09:40 PM
the reason they quote 15mm is that at 10mm lower or higher the speedo dosent alter at 15mm it is with in 10% allowerable after that the speedo is way out needs to be calerbratied to be legal

01-09-2003, 09:19 PM
I called today and got the same answer from the RTA. The guy sounded like he'd rather be in bed though :?

Anyways, with my tyre placard saying the largest wheel for the Laser was 15x6 I'm assuming it's safe to go as high as 17x7 (keeping same wheel/tyre diameter) and maybe 18x7 if you wanted?

You Astina guys probably got larger wheels as standard though right?


02-09-2003, 03:38 PM
You have to watch it...

I think the widest wheel fitted to a 4 pot Astina (on the tyre placard) may have been a 6"

On the v6 it may have been a 7"?

Which means the wheel maxes are different between them, also make sure you're insurance company won't freak. One will only let you go 1" wider and 1" larger diameter, others will stop you at 1" wider and 2" diamter. And yet others will not really care as long as it's legal...

Then you get to start on the load index of the tyres - which you have to make sure you don't fit tyres with a lower load index than stock.... If you do it's against the rules, and a technical defect usually voiding insurance as well...