Rear tyres on Z3 - Is this illegal?

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Keynun
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Rear tyres on Z3 - Is this illegal?

Post by Keynun » Sat 20 Dec, 2014 18:37

Could someone advise whether this tyre is still legal to use?
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I'm getting serious wear on the insides on the rear tyres. Car is lowered on coilovers. Seems like excessive negative camber + toe out of spec has caused this? I think I've done around 12,000 miles on these tyres plus some hard driving/1 track session, the have around 4mm left on the outside. Sadly nothing in the rear is adjustable, which is a bitch.

gas guzzler
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Re: Rear tyres on Z3 - Is this illegal?

Post by gas guzzler » Sat 20 Dec, 2014 22:04

Looks as if it is, min requirement is 1.6mm over 3/4 width of tyre.
Andy

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TR4man
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Re: Rear tyres on Z3 - Is this illegal?

Post by TR4man » Sat 20 Dec, 2014 22:47

Although you might want to have your tracking checked

Keynun
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Re: Rear tyres on Z3 - Is this illegal?

Post by Keynun » Sun 21 Dec, 2014 01:23

Would that not technically have 1.6mm+ over 3/4 of the tyre? I've ordered two tyres anyway.

Can't really do much with tracking on the rear tbh. I've got new coilovers on there so I will get an alignment and check done though.

gas guzzler
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Re: Rear tyres on Z3 - Is this illegal?

Post by gas guzzler » Sun 21 Dec, 2014 07:28

Keynun wrote:Would that not technically have 1.6mm+ over 3/4 of the tyre? I've ordered two tyres anyway..

Sorry I phrased that wrong, yes it is ok.
Andy

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1999 Z3 2.8 SILVER

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Mike123
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Re: Rear tyres on Z3 - Is this illegal?

Post by Mike123 » Sun 21 Dec, 2014 08:00

I think common sense takes precedence over legality.

It comes down to where and how you drive. On a dry track there would be plenty of grip from these tyres, on a very wet road minimal grip as there's nowhere for the water to go, so the tyre doesn't make effective contact with the road. If you drive slowly enough you probably won't be a danger to yourself and others - but why take the risk?

Del
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Re: Rear tyres on Z3 - Is this illegal?

Post by Del » Sun 21 Dec, 2014 09:44

It's an unavoidable characteristic of lowering the Z3 more than a tiny bit - seen lots of posts about this in the past. :(

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Re: Rear tyres on Z3 - Is this illegal?

Post by pedro20001 » Sun 21 Dec, 2014 10:10

Another characteristic on non adjustable rear suspension! camber is great for cornering but wear rates take a beating. I can get 20k out of my rears (245/40r17) on sport suspension but lowering pretty much halved that for me!

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Captain
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Re: Rear tyres on Z3 - Is this illegal?

Post by Captain » Sun 21 Dec, 2014 10:19

With directional tyres you should swop them over every so often, left to right this will increase the mileage you able to get out the rear tyres. Just means having to have them unmounted and remounted.
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Joycey
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Re: Rear tyres on Z3 - Is this illegal?

Post by Joycey » Mon 22 Dec, 2014 09:26

Your going to get that type of wear with the car being lowered, How much have you dropped the car by?

I dropped my "M" by 35mm and the tyre wear is only marginally off on the rear.

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Dino D
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Re: Rear tyres on Z3 - Is this illegal?

Post by Dino D » Mon 22 Dec, 2014 17:57

You will get wear on the inside edge on any BMW and more so the Z when lowered.

As Captain said above swap the tyres over. It's what I do to double the life. I do it every 5-6k miles. The 12k miles you got on those is very good going in my book.

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Gazza
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Re: Rear tyres on Z3 - Is this illegal?

Post by Gazza » Mon 22 Dec, 2014 18:27

Response to the original question.............Yes
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Re: Rear tyres on Z3 - Is this illegal?

Post by gookah » Mon 22 Dec, 2014 22:43

Gazza wrote:Response to the original question.............Yes
Which question is that? the title question that asks "is this illegal",
or the first line of the first post that asks "is this legal"?

I say no,
but I am not saying which question that I am answering..... :D
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Keynun
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Re: Rear tyres on Z3 - Is this illegal?

Post by Keynun » Mon 22 Dec, 2014 23:16

In conclusion, I will use the LSD effectively and the replace these tyres.


Thanks for the advice guys :twisted:

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pingu
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Re: Rear tyres on Z3 - Is this illegal?

Post by pingu » Tue 23 Dec, 2014 01:47

Keynun wrote:Could someone advise whether this tyre is still legal to use?
Image

I'm getting serious wear on the insides on the rear tyres. Car is lowered on coilovers. Seems like excessive negative camber + toe out of spec has caused this? I think I've done around 12,000 miles on these tyres plus some hard driving/1 track session, the have around 4mm left on the outside. Sadly nothing in the rear is adjustable, which is a bitch.
http://www.motinfo.gov.uk/htdocs/m4s04000107.htm

You would have to check it with a ruler, but it looks like the central 3/4 of the tyre has a continuous 1.6mm tread. If it is, it's legal.

But, I'd change it.
Pingu

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Rear tyres on Z3 - Is this illegal?

Post by Boysie » Wed 24 Dec, 2014 14:04

Mine don't wear they just get old :-)


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Zedbedee
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Re: Rear tyres on Z3 - Is this illegal?

Post by Zedbedee » Fri 26 Dec, 2014 11:47

I was interested in this as my rear tyres seem to be wearing in a similar way. I have the staggered 17" wheels with the wider ones on the back and I also seem to have quite a lot of negative camber. Looking at other Z3's they all seem to have negative camber on the back so I assume they all wear their tyres unevenly. Is this right??

littlefeller
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Re: Rear tyres on Z3 - Is this illegal?

Post by littlefeller » Sat 27 Dec, 2014 21:28

yes its legal (technically) however it could also be argued that when the tyre is fitted to the car the whole tyre isn't getting used hence the scrubbing, so it could be argued that your driving on the bold side of the tyre. this would be difficult to prove but if you annoyed plod enough they may take this view. personally It wouldn't bother me too much, I have had worse. suppose if you think about it, theres more tred there than on a spacesaver :lol:

t-tony
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Re: Rear tyres on Z3 - Is this illegal?

Post by t-tony » Sat 27 Dec, 2014 23:44

Plod could argue what they like and you would be well within your rights to tell them to take a hike. I had to pass and advise on a pair of tyres a couple of weeks ago which were on 1.8mm ( measured with a digital depth gauge) and my manager at work tried to give me a Bo.....ng until I printed the page off the tester's manual and put it in front of him. I had to agree those tyres were absolutely useless and I wouldn't want them on my car but until the DVSA change to rule on tread depth my hands are tied.

Tony.
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David Maxwell
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Re: Rear tyres on Z3 - Is this illegal?

Post by David Maxwell » Thu 01 Jan, 2015 16:34

It might be worth exchanging rear wheel tyres, L to R and R to L (not wheels). This may give you at least another 6-9000 miles from your rear tyres, provided your mechanic agrees that they are still legal?

David.

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Re: Rear tyres on Z3 - Is this illegal?

Post by t-tony » Thu 01 Jan, 2015 17:47

Absolutely David, this is by far the best way to get the most use/wear out of rear tyres. All it costs is a few ££ at your local tyre house to swap them on the rims and re balance.

Tony.
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TomH84
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Re: Rear tyres on Z3 - Is this illegal?

Post by TomH84 » Thu 01 Jan, 2015 19:20

That's a great idea. I'm going to try the same at my local independent tyre shop this week.

My flalken ze914s have worn exactly the same. Would be great to get another 5k out of them before replacing. They are only 12months old.

Tom
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