The 21" Tire dilemma . (long) - Page 4 - The Unofficial BMW M5 Messageboard (m5board.com)

Amjad Ali · 30th September 2005, 23:33

Quote:

Originally Posted by sydl

What has? The wheels? I'm not talking about the wheels.

The issue is whether a non-OEM tyre, on a car is covered by the car owner's insurance. Passing a TUV test is not what our laws and local authorities and insurance company looks at. All they care about is whether the tyres (not wheels) are as per the manufacturer's specifications. It's really got nothing to do with the wheel manufacturer Hartge - it's the driver/owner - the person who sold/put the tyres on the car.

The TUV process invloves testing of both the wheels and tyres.

The final TUV certificate states the vehicle, wheel sizes, and exact tyre sizes and manufacturer(s) in most cases if they have tested more than 1 tyre. The TUV would highlight the fact that the tyre is not correct. The way they check if the tyre is correct for the car is by using TUV's data of that particular car, which in this case has been supplied to them by BMW. Believe me if the tyre was not as per manufacturers specification then they would not approve it for TUV.

I hope that clarifies it.

Amjad Ali · 30th September 2005, 23:37

Quote:

Originally Posted by m5-black

One other Insurance matter that was raised was durabiity, as In Ireland and some parts of the UK pot holes are a real problem and seeing as the 21" Tires are

255 / 30
295 / 25

Maybe with our less then stellar rural roads, these might be risky.

any opinions on the durabilty of Contis in the /30 /25 range

Hi M5-Black

I have not used 21" conti's but have used Conti's in 255/30/20's and 305/25/20's sizes on SL55 AMG's with no problems. Yes you will have to be a bit careful when you drive them on bad roads, but that is accepted when you are running such low profiles.

And to think my first Alpina B9 ran 225/50/16's on the rear and I thought they were low profile and really wide!!!!

sydl · 1st October 2005, 00:28

Quote:

Originally Posted by m5-black

I've called The NCT people - Ireland's MOT and spoken to the insurance company.

The NCT will pass the tyres they have absolutely no issue with them as long as they are fitted and inflated correctly

The insurance company had no problem, they just wanted to know it would pass the NCT.

Very interesting - sounds like your authorities and insurers aren't as strict as down under.

It sounds like they don't care about load rating.

Amjad Ali · 1st October 2005, 01:08

Quote:

Originally Posted by sydl

Very interesting - sounds like your authorities and insurers aren't as strict as down under.

It sounds like they don't care about load rating.

Sydl the insurers here would not even know what a load rating was!!!

All they ask is are you running aftermarket wheels what they cost and if they increase the value of the car.

frylord · 1st October 2005, 04:07

Quote:

Originally Posted by Amjad Ali

Sydl the insurers here would not even know what a load rating was!!!

All they ask is are you running aftermarket wheels what they cost and if they increase the value of the car.

Same over here aswell. I can imagine that this is something that wouldn't apply to a "regular" road going car which can barely reach 200km/h (124mph) and doesn't do the hard acceleration and breaking an M5 does. If you fit 17, 18 or maybe even 19 inch rims under a "ragular" car then I can imagine that there is a very wide range of tyres you can choose from and almost any tyre will do. These cars probably make up 99% of their bussiness.

But for a car like the M5 or whatever other "supercar" (I don't concider the M5 to be a supercar cause it's not supposed to be, although it is) which can easily run +300 km/h and can do very hard acceleration and breaking this becomes a mayor safety issue. But because it's not part of their everyday bussiness they're not aware of it or simply don't care.

Ofcourse this is sepculation but it should be something every M5 owner should be aware of, make sure you have the correct tyres before you decide the pull the throttle to full or else very bad things might happen. Specialy make sure the pressure in your tyres are correct before doing 250 or 300 km/h cause it's very easy to destroy your tyres at those speeds.

frylord · 3rd October 2005, 01:33

Quote:

Originally Posted by Amjad Ali

Sydl the insurers here would not even know what a load rating was!!!

All they ask is are you running aftermarket wheels what they cost and if they increase the value of the car.

Okay I did some research on the subject and this might come as a shock.

If you get a aftermarket exhaust then you need a certificate saying the new exhaust conforms to sound and emission regulations.

If you get your front windows tinted (rear can be as dark as you want) you need a certificate saying the windows still have a x percentage shine through and have good visibility.

But if you get new wheels, you don't need anything.

m5-black · 3rd October 2005, 01:38

Quote:

Originally Posted by frylord

Okay I did some research on the subject and this might come as a shock.

If you get a aftermarket exhaust then you need a certificate saying the new exhaust conforms to sound and emission regulations.

If you get your front windows tinted (rear can be as dark as you want) you need a certificate saying the windows still have a x percentage shine through and have good visibility.

But if you get new wheels, you don't need anything.

Yep same here - As noise and emissions get tested during our National Car Test Agency test - and Tinted windows will be checked

Whereas Tyres - only have have correct tread, be fitted correctly, have no serious damage and not protrude too far.