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LU-RS6
January 5th, 2007, 14:37
I have Bridgestone Blizzak LM-25 installed, 225-45R18 95V

I know V stands for max 240km/h. Have googled a bit and found that tires would explode if you are driving 30km/h over the tire speed indication during 30 minutes..


Does this mean it wouldn't hurt getting to 260-270 km/h for a minute or 2? Or do you guys think I'd better not try ?:nono:


Best regards
LU-RS6

Speedou
January 5th, 2007, 15:34
Have been driving 250km/h with only Q (160 I think) tyres. Those where only quite slack after that. So I wouldn't be scared driving 270 with V tyres.

LU-RS6
January 5th, 2007, 16:13
Thanks for yr reply.

250 with 160 tires lol that's pretty insane :dig:

I think I should be able to easily drive 260/270 tacho. After all 240 tacho is only real 228km/h.

jonas21
January 5th, 2007, 18:49
You should really be very carefull with winter tires. There have been numerous reports in magazines about exploding tires after even 15mins of over 30km/h more than spec. I personally dont see a problem to do 10km/h more all the time (which i mostly do) but not more. To overtake somebody and do 20-30km/h more for a minute or so shouldnt be a problem...atleast i havent had any yet (and i drive alot).
You know....better safe than sorry.

Btw, i really love the tyre pressure warning system....saved me one time. Was going 120km/h (speed limit...duh) and limit was just about to be waived and i was about to push and then suddenly i got the red alarm from the left front tyre. Stopped immediatly and like 1 minute after standing still there was absolutly no air anymore inside the tyre.

LIRS6
January 5th, 2007, 19:04
I would be concerned ref the load rating - 95 is not extra load, which is what our cars require. That in combination with the speed rating would certainly keep me well below their rating - time for new snows, I would say.

Qisha
January 5th, 2007, 20:06
Dear LU-RS6,

i can highly recommend to NOT override the speedindex!

The speedindex refers to the maximum speed of the tyre apending to the load-carrying capacity index.

Example:

Your tire is within the specs for the RS6: 225/45 R18 95V

95V say that the tire is able to carry 690kg BUT at a speed of 240km/h only 91% of the maximum = 623kg! The faster you go, the less weight the tire is able to carry. Another issue is the pressure, a tire that is running over its specs will heat up, pressure is rising and this will lead to a exploding tire.

As jonas21 mentioned, this is why Audi uses the tire monitoring on the RS6, a safety feature.

PS: the reason why Audi is de-limiting the RS6 (plus) to max 280km/h are the tires. (as Audi -and the tire manufacturers also- see the risc for accidents). The maximum continues certified speed within the RS6 specs (255/35 R19 96Y) is 288 km/h, everything over is at your own risc.

LU-RS6
January 6th, 2007, 20:24
Thanks all for your replies, appreciate it!

Most of the time I am staying under 240 kmh on tacho which is about 228kmh real. I've put up a speedwarning in the car at 240kmh, and it only sounded when I was doing about 260 kmh tacho.

Yet you are all right it is better no risk your life to be a few seconds faster...I will wait till summer till I go all the way again.

offtopic: Have shot a short movie yesterday of 0-250 kmh. Think there will be any difference with the gearbox in Sport instead of just doing a kickdown?
http://www.youtube.com/watch?v=QSBvJZRuvVs





Best regards and enjoy your weekend,
Lu-RS6

jonas21
January 7th, 2007, 14:59
PS: the reason why Audi is de-limiting the RS6 (plus) to max 280km/h are the tires. (as Audi -and the tire manufacturers also- see the risc for accidents). The maximum continues certified speed within the RS6 specs (255/35 R19 96Y) is 288 km/h, everything over is at your own risc.

When Wetterauer tuned my RS6 they asked Continental about their Conti Sport Contact 2 tyres (they are marked 300km/h max) wether they could do more. Conti replied with a certificate that they had no objections but said that one has to raise the pressure 0,3 bar on each tyre. Ive got the paper somewhere....if anyone is interessted.

noushy
January 7th, 2007, 16:06
I would be very careful with winter tires. Follow their labels to a T. I ran pirelli wintersport tires, with the proper load rating and speed rating of V (97V) to be exact. They were designed to handle the weight and speed of the RS6. They were excellent in the snow, and were very tolerable in dry weather. Obviously they did not corner as well as the summer tires, but overall the correct winter tire here in michigan. I now have the same tires (different sizes of course) for my M6 and put a lot of trust in them. I have ran Blizzaks, and Pilot Alpins, and the pirellis are my favorite snow tires. The Michelins are a close second.

Peace,
Noushy

Lateknight
January 7th, 2007, 21:01
Best err on the side of caution.
A blow out at 260km/h would at best heavily damage/write off your car...at worst write you off..!!

Your tyres are a very critical part of your expensive car. Not worth the risk for such little gain.
Wait until summer to blow the cobwebs out of your car on Hi-Po summer tyres.

Aronis
January 8th, 2007, 03:48
Pirelli Wintersport 240's, V rated (149 mph) which is more than enough for me...I have driven frequently with the snows fast (not saying how fast here LOL) and no problems, no wear issues (getting more miles than summer tires) and the dry road handling is not that bad.

Mike

LU-RS6
January 8th, 2007, 08:08
Still I find it "unfair" of the car producers to install a gap between real speed and tacho speed. Somehow I understand there should be a gap for safety procedures (lawsuits and everything), but when I enter a speedwarning at 240 kmh it won't sound untill I'm right before 260 kmh on the tacho which I find a bit disturbing.

noushy
January 8th, 2007, 19:18
I actually have sottozeros now, wintersporsts on the RS6. As I said before, excellent snow tires, run very nice even at speeds well over 100mph.

Peace,
Noushy