Tyre markings
26 February 2004, 12:00 AM
#1
Scooby Regular
Thread Starter
Join Date: May 2002
Posts: 399
Likes: 0
Received 0 Likes
on
0 Posts
Tyre markings
Have seen a set of goodyear eagle f1 gsd3's in 215/40/17 Y 83 (so)
The Y is the speed rating, is 83 the hardness of the tyre compound?
I have seen the same size tyre but with ZR on the end. Are these two tyres different. Obviously the tread pattern will be the same and a slightly different speed rating.But are they a different compound/ sidewall stiffness to the ZR?
The Y is the speed rating, is 83 the hardness of the tyre compound?
I have seen the same size tyre but with ZR on the end. Are these two tyres different. Obviously the tread pattern will be the same and a slightly different speed rating.But are they a different compound/ sidewall stiffness to the ZR?
26 February 2004, 12:42 AM
#2
Scooby Regular
Join Date: Jan 2002
Location: South East London
Posts: 739
Likes: 0
Received 0 Likes
on
0 Posts
I cant comment on the chemistry of the actual tyres but the Toyo site is good for explaining all the markings on the side of the tyre. http://http://www.toyo.co.uk/index.p...car.speedindex for the speed index and http://http://www.toyo.co.uk/index.p...=car.loadindex for the load index.
In your case I think it was actually probably 215/40/17 83Y - the '83' is the load capacity of the tyre. So, the tyre you mention has a load index off 487kg going of Toyo's table.
ZR is an old speed designation (the change must have been quite recent as I think ZRs are still in circulation - mine are ZR - probably old stock). Now it is just one single letter (well, for us anyway).
There is actually a better site detailing the ZR/Y etc business - I will see if I can dig it up.
John
In your case I think it was actually probably 215/40/17 83Y - the '83' is the load capacity of the tyre. So, the tyre you mention has a load index off 487kg going of Toyo's table.
ZR is an old speed designation (the change must have been quite recent as I think ZRs are still in circulation - mine are ZR - probably old stock). Now it is just one single letter (well, for us anyway).
There is actually a better site detailing the ZR/Y etc business - I will see if I can dig it up.
John
Last edited by JohnMcC; 26 February 2004 at 12:44 AM.
26 February 2004, 12:54 AM
#3
Scooby Regular
Join Date: Jan 2002
Location: South East London
Posts: 739
Likes: 0
Received 0 Likes
on
0 Posts
I can't find it now - maybe tomorrow.
Basically, it's that ZR is simply rated to over 150mph, but the top speed wasnt really specified. I guess, as cars have got faster they have had to specify exactly what speeds over 150mph the tyres work to. So Y has been tested to 186.4mph.
I doubt there is really any difference between the two in terms of the chemistry - other than tweaks and changes that happen to every product over time.
John
Basically, it's that ZR is simply rated to over 150mph, but the top speed wasnt really specified. I guess, as cars have got faster they have had to specify exactly what speeds over 150mph the tyres work to. So Y has been tested to 186.4mph.
I doubt there is really any difference between the two in terms of the chemistry - other than tweaks and changes that happen to every product over time.
John
Last edited by JohnMcC; 26 February 2004 at 12:55 AM.
Thread
Thread Starter
Forum
Replies
Last Post
Mattybr5@MB Developments
Full Cars Breaking For Spares
28
28 December 2015 11:07 PM
Mattybr5@MB Developments
Full Cars Breaking For Spares
12
18 November 2015 07:03 AM