Grip Rating On Tyres

[Never had any say Panda]

I'm just curious and I've done a bit of searching and turned up nothing that is very descriptive.

Some tyres (not all) seem to have an grip rating advertised with them. I haven't actually checked mine but a mates Achilles (Tread wear 400) tyres have an A++ Grip rating and recently while researching tyres (tread wear 240) I was looking at some that advertised a AA grip rating.

So the question: What the hell is the grip rating? How do they determine the grip rating of a particular tyre? And what does it actually mean to us who purchase the tyres?

Cheers,

[MexicanBatman]

its all crap

my drag radials are B traction and I swear I was pooping wheelies at the drags, the TWI of my radials is 00 though

I think there is a tyre wiki that explains it all though, I dont believe it much anymore as my current 300 twi tyres grip loads better than my previous 200 twi tyres both AA A

[sexual harrassment panda]

I seem to remember the traction rating was the results of a braking based test.

treadwear is meant to be a standardised type of test where a tyre is placed on a roller and driven at a set speen to see how long it lasts.

[Vevapower]

Pretty easy way to rate grip levels, the lower the tread wear the gripper the tyre!

400+ = sh*tTTY grip

200 = Nice street grip for + 300 kws

00 = best grip but will only last about 2 months on the street!

[dbXR60]

Nearly all tyres are required to have a Universal Tyre/Tire Quality Guide (aka UTQG).

It often looks like 280 AA A, 460 B C etc. I think it's always stamped on the tyre, though it may not be readily available in advertising or specs provided by companies.

The number is the treadwear rating, followed by a traction rating, then a temperature resistance rating.

Here's an explanation of UTQG.

The traction/grip rating says: "UTQG Traction Grades are based on the tire's straight line wet coefficient of traction as the tire skids across the specified test surfaces. The UTQG traction test does not evaluate dry braking, dry cornering, wet cornering, or high speed hydroplaning resistance". Sound pretty useless?

I'd pay more attention to the ratings of tyre tests and, eg from people surveys over at Tirerack than the UTQG ratings.

Unless all you do is brake in the wet....

Edited 11/11/11 07:01 AM by dbXR60