Z3 staggered wheels

Neil Wilson

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Jul 11, 2019
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I have a set of staggered wheels available at a good price. 7.5j 17 et 37 and 8.5j 17 et 47. I believe the standard offset for staggered wheels on the Z3 is et 41 front and rear so the fronts will be 4mm wider and rears 6mm narrower than standard. Will this be ok. I have 225 45 17 tyres all round on my car currently on 7.5j 17 rims so assume I can use those tyres on the fronts matched with 255 40 17 on the rear?
 

Dakar Z3

Dakar
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Hello,

The correct rear tyre size is 245 40 17.
 

Neil Wilson

Dedicated Member
Joined
Jul 11, 2019
Points
33
Hello,

The correct rear tyre size is 245 40 17.
I thought that but a 245 40 17 is slightly smaller diameter than a 225 45 17, a 255 40 17 is exactly the same size? As the offset on the wheels I have available on the rear is greater than standard would the extra width of the 255 make up for the 6mm I’m gaining on offset?
 
Last edited:

Pond

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I thought that but a 245 40 17 is slightly smaller diameter than a 225 45 17, a 255 40 17 is exactly the same size? As the offset on the wheels I have available on the rear is greater than standard would the extra width of the 255 make up for the 6mm I’m gaining on offset?
www.willtheyfit.com
Everything you need is on this website.
 

Nodzed

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Not sure what you are saying here, the offset has nothing to do with the width of the tyre or wheel.
 

Mike Fishwick

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What do you think your insurer will say about this?
 

Scooblitz

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255/40/17 on the rear will be absolutely fine.

I run 255/40s on even lower offset wheels without fuss.

You would also be correct that 255 is a better partner for a 225 than a 245. However 245 is indeed what bmw ask for and is within the tolerance levels for rolling road radius.

If they are bmw wheels, I doubt any insurers would have issue without any 'declaration of mods'.

Stevie
 

Pond

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What do you think your insurer will say about this?
If you tell them no doubt they would want to charge you more.
Why you would NEED to tell them, though, is another matter.
This modern idea of telling insurers if you put a different octane level of fuel in is a mystery to me. :rolleyes:
 

GZed

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If you tell them no doubt they would want to charge you more.
Why you would NEED to tell them, though, is another matter.
This modern idea of telling insurers if you put a different octane level of fuel in is a mystery to me. :rolleyes:
Insurance companies couldn’t give a monkey’s whether you tell them about any mods or not. In fact, they love it when you don’t declare anything, which is exactly the reason you NEED to declare everything. Why? Because insurance Contracts occupy a very strange corner of Contract Law known as ‘Contracts of Utmost Faith’ In this type of contract the insurer doesn’t check any of the details you provide, instead they place the ‘utmost faith’ that what you have told them is true, correct and complete.
‘Utmost Faith’ means the onus is all on you. It’s only once you make a claim that the insurance company starts to check; If they find anything that wasn’t declared that should have been, then the contract (of utmost faith remember) becomes null & void. The insurance company keeps your premium and you get nothing- that’s why they love it if you don’t declare things.

And remember, the bigger the claim, the deeper they’ll dig in order to get themselves out of it. If the claim involves death or injury of a third party, the costs could be astronomical. Insurance company finds something not declared, they’re off the hook, leaving you personally liable to find the money instead.

Hence the old adage ‘if in doubt, declare it’. Sometimes it may add a few pounds to your premium, sometimes not. But at least you can rest safe in the knowledge you’re covered for the worst case, which is exactly when you’ll need it most.
 

Pond

Zorg Guru (III)
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Insurance companies couldn’t give a monkey’s whether you tell them about any mods or not. In fact, they love it when you don’t declare anything, which is exactly the reason you NEED to declare everything. Why? Because insurance Contracts occupy a very strange corner of Contract Law known as ‘Contracts of Utmost Faith’ In this type of contract the insurer doesn’t check any of the details you provide, instead they place the ‘utmost faith’ that what you have told them is true, correct and complete.
‘Utmost Faith’ means the onus is all on you. It’s only once you make a claim that the insurance company starts to check; If they find anything that wasn’t declared that should have been, then the contract (of utmost faith remember) becomes null & void. The insurance company keeps your premium and you get nothing- that’s why they love it if you don’t declare things.

And remember, the bigger the claim, the deeper they’ll dig in order to get themselves out of it. If the claim involves death or injury of a third party, the costs could be astronomical. Insurance company finds something not declared, they’re off the hook, leaving you personally liable to find the money instead.

Hence the old adage ‘if in doubt, declare it’. Sometimes it may add a few pounds to your premium, sometimes not. But at least you can rest safe in the knowledge you’re covered for the worst case, which is exactly when you’ll need it most.
I agree and also disagree.
As long as the vehicle insured meets the manufacturer's 'standard' specification (ie no mods) then there is nothing to declare.
The standard specification of, in this instance, a Z3 can be very diverse. Doesn't mean if you specified your car with dealer supplied (approved) wheels of 18" rather than 16" there is anything to declare.

I keep hearing people bleating on about changing run-flat tyres for non-runflats and making sure you alert your insurers. Nonsense. As long as the tyres are road legal and of the correct size and specification, the insurers have no business knowing.
 
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