A steering saga...

[Liam2594]

Out of interest, are the tyres on your car marked with BMW's little star?

[Andrew]

Mine are all star marked. 

[Andy5150]

Ohh, what’s this star mark? Incidentally I had read that modern BMWs should always have four of the same tyres. I wish I knew that before change my rears for a different brand. I read an excellent article about someone with an M3 that had months (maybe even a year) of stability problems only to eventually find out from a chance meeting with a BMW test driver that the front and rears were different brands - standardising them front and back solved the problem instantly.

I’ve been to Swindon today and was thinking about Duncan’s steering feel comments. So 2 hours driving have me a chance to evaluate mine. Conclusion is that the steering only wanders in ruts or occasional off-cambers but when it does it’s pretty bad - MUCH worse with different brands front & rear. Steering behaviours is perfectly fine at speed and around town (unlike Duncan’s) but lateral body control over uneven roads is pretty rubbish. Mine is a Luxury model so has the standard SE suspension but the spirited drive home across some empty wide Cotswold roads really revealed how poor the body control is over anything other than level smooth tarmac. I can only assume it’s my rear dampers as the back feels like it skips slightly on mid corner bumps and there’s definitely more lean than I’d expect. Still, at £600 for the pair fitted I’ll have to grin and bear it for a while.

Duncan - do you have the same tyres all round?

Edited May 18, 2023 by Andy5150

[duncan-uk]

I fitted 4Nº Michelin PS5 not long after i bought it, thinking runflats where the issue. (ATS had a deal and my bank did a kick back so not quite as flash as you might think!)

[Andrew]

59 minutes ago, Andy5150 said:

Ohh, what’s this star mark? Incidentally I had read that modern BMWs should always have four of the same tyres.

Star marked tyres mean they are approved by BMW and are runflats in my cars case.

All cars should have four tyres of the same spec. That’s basic common sense. 

Different specs of tyres on front/rear can lead to unpredictable handling. 

The previous owner of my car specced budget ditch finders (very non star marked) on the rear that cracked after 18 months. I couldn’t wait to bin them for star marked Michelins 

[duncan-uk]

I bought a can of goo and an compressor as per the m cars but I am tempted to buy a space saver kit if I decide to keep the car long term. 

[skyjawa]

Also the white dot on the tyres should align with the valve but hardly any fitters ever do this.

[Andrew]

^I've spoken to tyre fitters who said in 30 years of fitting tyres, he'd never heard of that.....

[Andy5150]

9 hours ago, Andrew said:

All cars should have four tyres of the same spec. That’s basic common sense. 

I think this enough encouragement for me to change my fronts now. I’ve always had company cars before and got used to the same Alex Autolease approved standard for, so I neither cared about cost or brand - they were always the same. However, I guess I’ve learned through some unpredictable feel that maybe the front and tears (although both good brands) being different is partly contributing to the stability concerns I have.

[skyjawa]

54 minutes ago, Andrew said:

^I've spoken to tyre fitters who said in 30 years of fitting tyres, he'd never heard of that.....

Its quite well documented on the web, tyre manufacturers place a white dot on them so the fitter can align with the valve and this gives the best chance of ensuring the tyre/wheel  is balanced as best as it possibly can be.

[Andrew]

12 minutes ago, skyjawa said:

Its quite well documented on the web, tyre manufacturers place a white dot on them so the fitter can align with the valve and this gives the best chance of ensuring the tyre/wheel  is balanced as best as it possibly can be.

Oh you are absolutely right, just no one has ever mentioned it to all tyre fitters.

 

Although, be careful what you read on the big bad internet, especially about F10 BMWs, I mean some of it is put there by idiots, like me😆

 

 

When I had a puncture on one of my fronts, I swapped the front axle for 17" rft Dunlop winters and ran the rears on 19" rft Michelin Primacy 3's.

I dared not drive it quickly in the bends.

[Andrew]

An example of the star marking that means it’s a BMW approved tyre.

 

[Liam2594]

Always found that the star marked tyres make a difference. You can get them in non-RFT too. 

[Matthew]

On 19/05/2023 at 08:33, skyjawa said:

Also the white dot on the tyres should align with the valve but hardly any fitters ever do this.

Not actually with genuine BMW wheels and associated tyres. The white dot on the tyre should be aligned with a white dot that may be painted on the inside of the rim during manufacture.

In the day when there were red and yellow dots on tyres, these were aligned with the vale on steel rims but less necessary with the relatively uniform manufacturing process for alloy wheels today.

 

Edited May 25, 2023 by Matthew

[Kopfjaeger]

What happens if you get your genuine wheels refurbished? I don't recall seeing a white dot on the insides of my refurbished 303M rims?

[Matthew]

On 22/05/2023 at 10:12, Kopfjaeger said:

What happens if you get your genuine wheels refurbished? I don't recall seeing a white dot on the insides of my refurbished 303M rims?

Of course not as they will have been repainted and the dot will be long forgotten.

[Kopfjaeger]

My point is how important is the 'white dot' on the wheel? Wheels are usually balanced with tyres on. If the mark on the wheel was important, shouldn't it be a permanent mark, like an engraving, etc?

[duncan-uk]

One assumes its cost and you just have more weights added to compensate?

[Andrew]

The white dot is to line up with the valve, which in theory is there is more rubber in the tyre in the opposite side to the white dot to compensate for the weight of the valve so the tyre is already compensating for the valve so you won’t need any more additional balance weights for compensating of the valve. 
 

But as most tyre fitters don’t bother and how much weight a valve adds given there is a hole in rim. 
 

The pressure sensors in todays cars (required by law as folk can’t be relied upon to pump up their tyres) may be more critical in ensuring and white dot is lined up with the valve. The weight of a pressure sensor (with batteries) rotating at 70mph will be not insignificant. 

[Matthew]

7 hours ago, Andrew said:

The white dot is to line up with the valve, which in theory is there is more rubber in the tyre in the opposite side to the white dot to compensate for the weight of the valve so the tyre is already compensating for the valve so you won’t need any more additional balance weights for compensating of the valve. 
 

But as most tyre fitters don’t bother and how much weight a valve adds given there is a hole in rim. 
 

The pressure sensors in todays cars (required by law as folk can’t be relied upon to pump up their tyres) may be more critical in ensuring and white dot is lined up with the valve. The weight of a pressure sensor (with batteries) rotating at 70mph will be not insignificant. 

No, BMW, on some of their rims add a white dot on the barrel itself which the white dot on the tyre is aligned with. In the old days of steel rims the “high” spot was generally the valve area hence the tyre alignment to the valve to reduce the grammage of weights needed. On cars with alloy wheels, the manufacturing tolerances are such that this practice is now almost forgotten.

At Tiger Wheel and Tyres in South Africa, if they went to balance new tyres and the machine called for a large number of grammes of weights, they would break the bead again and rotate the tyre on the rim to reduce the weights needed. I’ve never seen anyone in the U.K. take this level of care, they just shove on a load of weights and be done with it. I’ve also found that Michelin tyres that I’ve had fitted to many of our cars need fewer weights than other brands. 

[Andy5150]

Quick update to my posts above; car going in tomorrow for new rear dampers (my F11 has now tipped over 102k and feels too bouncy for my liking at the back now) and a set of Hankook Ventus S1 Evo3 for the front to match the rears I had fitted back in Dec (which I notice do indeed have stars on them!).….Will report back on whether the handling/body control is improved at all. I’d hope so at nearly £1k all in!

Edited May 31, 2023 by Andy5150

[Steve84N]

If they charge you any more than one hour of labour for the rear dampers you're being robbed. All accessible from within the wheel arch and a very easy job. 

[Andy5150]

29 minutes ago, Steve84N said:

All accessible from within the wheel arch and a very easy job. 

I meant to add that the top mounts are also being replaced as these had shown signs of degradation too - this bumped the cost up somewhat. I got 3 quotes from a couple of normal garages and bmw specialist and all were surprisingly close. Everything seems to cost more here in Buckinghamshire. Sometimes I think it’s more expensive here than London! 

[duncan-uk]

Have you tried CPC in Amersham?

[Andy5150]

I recall you saying you’d used CPC Duncan? Trouble is, I’m north Bucks so a bit a trek down to Amersham - would probably need to take a day off. I’ve heard good things about them though. Might use them to do my brake reaction bushes next year.