BMW E85 and E86 Wheels and Tyres Thread

[enuff_zed]

Thank you to those who commented on my original post! Even I refer to it at times! :lol:

Mr Tidy has given some good info, but I'll add a little as well (in the spirit of knowledge and sharing - by all means I'm no expert).

My understanding is that a square set up is regarded better for handling, although in the real world I'm not sure whether any of us would realise? However that being said I think the square set up is from the alloy and tyre combination. So you'd need a square set of alloys (both 8J for example). Then matching tyres to suit.

There are issues caused from over, and also under "tiring" a wheel. So while 245/40 on a 8.5J is acceptable, I'd be hesitant to put that much tyre on a 8J? I've seen some people run 215 on the front. Never usually seen people go the opposite way and add more width.

If it were me? I'd find out exactly what alloys I'm dealing with. Are they genuine? With the staggered front and rear? Or are they square?
If you're planning on keeping the MV2's style? Or fancy a change to something else? If so then it would be worth getting a cheap set online and getting them refurbished separately? MV3 or even Style 224 look great! You can then rubber them and swap wheels over at home? Then sell the original MV's and the crappy landsails in one go

Yet more excellent advice! Thank you.
I am kind of thinking back to 225 on the front tbh.
Vall likes the MV2s and I have to say the way they fill the arches, with their as yet unknown spec, looks great.
As everyone is saying, my first step must be to get a front and rear off and check the figures. The ET is not quite so relevant as the naked eye tells me they are a good fit, so it is down to the width of the rims really.
Weather looking better for this weekend so let's see if I can actually make progress :roll:

I'll repost a pic of the car here, so you can see what I mean about the way they fill the arches.
NB. The fronts are slightly turned to the left, so don't give a true picture

 

[kis]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

 

[mmm-five]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

The photo makes them look like they’re proud of the arch, so a decent hump/bump at speed and you’d bend the wing.

 

[enuff_zed]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

The photo makes them look like they’re proud of the arch, so a decent hump/bump at speed and you’d bend the wing.

Definitely not a spacer in there. I have quadruple checked as I thought there must be.
Car is on SE suspension and with the camber I'm pretty sure the travel would take it inside the wing?

Here's a better picture now I'm on my home laptop.

 

[enuff_zed]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

Hell! You made me so self-doubting I just went and checked again. There are NO spacers. Honest guv.

 

[Mr Tidy]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

Hell! You made me so self-doubting I just went and checked again. There are NO spacers. Honest guv.

If they fit like that with no spacer then I suspect the rears are going to be 8.5J - look forward to finding out of curiosity!

 

[mr wilks]

Those look staggered to me, and also fit way too good on the rear so suspect there will be a spacer at the back (suspect they are OEM as well). Anyone want to place bets? :lol:

Hell! You made me so self-doubting I just went and checked again. There are NO spacers. Honest guv.

If they fit like that with no spacer then I suspect the rears are going to be 8.5J - look forward to finding out of curiosity!

Looking at the concave spoke design I think they could be 8j et20 off a 5 series so looking forward to seeing the numbers once removed , the fronts look different style to rears so may be a mixed set ?

 

[Mr Tidy]

Looking at the concave spoke design I think they could be 8j et20 off a 5 series so looking forward to seeing the numbers once removed , the fronts look different style to rears so may be a mixed set ?

That would make sense - they certainly seem to sit further out than I'd expect for an ET50 8.5J wheel.

 

[enuff_zed]

Looking at the concave spoke design I think they could be 8j et20 off a 5 series so looking forward to seeing the numbers once removed , the fronts look different style to rears so may be a mixed set ?

That would make sense - they certainly seem to sit further out than I'd expect for an ET50 8.5J wheel.

Well now I have the 'city fathers' waiting on my findings, I really do need to get those figures!
My mission for the weekend.

 

[yyz_bobby]

Hi all

Need some advice

Owned my z4 E85 for 3 weeks

Currently has OEM 17" alloys and run flats. same one in my avatar pic.


Current tyre setup is:
Front: 225/45/17 and Rear: 255/40/17

First Question - why would my front tyre have lower profile than my rear? Barely noticeable when looking but curious.

I have seen a nice set of alloys for sale 18" and I think once I have these and some non RFs that my ride will be massively improved however I am concerned about whether they will fit without me having to touch spacers (not sure what these are to be fair) and/or if I need to take into consideration anything else? Eg brakes, cambers, strut? Could any of these be negatively effected?

The 18" alloys take tyres of the following measurements:
Front: 235/40/18 Rear: 255/35/18

Q1 - here the front is wider
Q1 - the tyres have a lower profile which I expect but that combined with the increase in alloy size would that still look better than what i have now?

Sorry for hijacking this thread.

Bobby

 

[Mr Tidy]

Bobby,

17" wheels are generally "square" so same rim widths front and rear, and usually same tyres sizes. But if someone fitted wider rear tyres they need to have a lower profile to maintain the rolling radius so that the speedo is accurate.

That's also why 18s run even lower profiles, although standard 18" rims are usually "staggered" so fronts are usually 8J x 18 and rears are 8.5J x 18. But the standard size for front tyres on those is 225/40 x 18.

But what you need to check is the rim sizes for both sets of wheels, including the offset, or "ET". BMW call it "IS" and it should be stamped on the wheels, usually on the rear face. The offset will determine how far out the wheels sit in the wheel-arches - spacers just sit them further out and many prefer that look.

Standard staggered 18s like MV2s and 108s are ET47 on the front and ET50 on the rear, but some other options from 3 series models and E89s will fit.

If you find all the wheel size and offset details you can see how they will fit by putting details on here:- https://www.willtheyfit.com/index.php?width=205&aspect=55&diameter=17&wheelwidth=7&offset=37&width2=235&aspect2=35&diameter2=19&wheelwidth2=8.5&offset2=20

Hope that is of some help.

 

[yyz_bobby]

Bobby,

17" wheels are generally "square" so same rim widths front and rear, and usually same tyres sizes. But if someone fitted wider rear tyres they need to have a lower profile to maintain the rolling radius so that the speedo is accurate.

That's also why 18s run even lower profiles, although standard 18" rims are usually "staggered" so fronts are usually 8J x 18 and rears are 8.5J x 18. But the standard size for front tyres on those is 225/40 x 18.

But what you need to check is the rim sizes for both sets of wheels, including the offset, or "ET". BMW call it "IS" and it should be stamped on the wheels, usually on the rear face. The offset will determine how far out the wheels sit in the wheel-arches - spacers just sit them further out and many prefer that look.

Standard staggered 18s like MV2s and 108s are ET47 on the front and ET50 on the rear, but some other options from 3 series models and E89s will fit.

If you find all the wheel size and offset details you can see how they will fit by putting details on here:- https://www.willtheyfit.com/index.php?width=205&aspect=55&diameter=17&wheelwidth=7&offset=37&width2=235&aspect2=35&diameter2=19&wheelwidth2=8.5&offset2=20

Hope that is of some help.

Thanks Mr T

I am currently watching youtube videos explaining Offset and ET but its nearly 12am and brain is already switched off since 6pm.

If you get the time this is the thread to the tyres I am considering:
https://z4-forum.com/forum/viewtopic.php?f=7&t=121580&p=1739528#p1739528

About half way up the seller "number 5" has tried to explain the fitting. But he is the seller and wants to sell.

So if you have the time if you can read his explanation using willtheyfit.com, can you confirm or give me your advice if these will fit okay without any potential future screw up. I plan to put on some decent P Zeros non run flats on the alloys if i buy.

Thanks
bobby

 

[where.is.lee]

Hi all

Need some advice

Owned my z4 E85 for 3 weeks

Currently has OEM 17" alloys and run flats. same one in my avatar pic.

Current tyre setup is:
Front: 225/45/17 and Rear: 255/40/17

First Question - why would my front tyre have lower profile than my rear? Barely noticeable when looking but curious.

I have seen a nice set of alloys for sale 18" and I think once I have these and some non RFs that my ride will be massively improved however I am concerned about whether they will fit without me having to touch spacers (not sure what these are to be fair) and/or if I need to take into consideration anything else? Eg brakes, cambers, strut? Could any of these be negatively effected?

The 18" alloys take tyres of the following measurements:
Front: 235/40/18 Rear: 255/35/18

Q1 - here the front is wider
Q1 - the tyres have a lower profile which I expect but that combined with the increase in alloy size would that still look better than what i have now?

Sorry for hijacking this thread.

Bobby

tyre profile relates to a percentage measurement of the tyre width not a millimetre measurement. so in your case your front tyres are a 45% profile of the 225mm width and rears are a 40% profile of 255mm width. all comes down to overall rolling diameter. What you will find is if you punch those figures into https://tiresize.com/tyre-size-calculator/ the rolling diameter front and back will be identical (this is important when looking for new wheels/tyres with +/- 3% to ensure your speedometer isn't thrown out of calibration)

RE the new 18s

do a quick search on http://www.bmwstylewheels.com/Z/Z4-E85+ and look up the specs (offset + width etc) of your current wheels and compare to the new wheels.

e.g. if the new wheels are the same width as your current 17s but with a lower offset then these wheels will sit that much closer to the outside of your guards.

e.g. if stock is 17x8 +40 and the new wheel is 18x8 +30 then your new wheel will protrude 10mm further outwards.

I use this online calculator to make an educated guess if wheels will fit.

https://www.1010tires.com/Tools/Wheel-Offset-Calculator

answering your question:

225/45R17 vs 235/40R18 : new tyre will be 1.72% bigger than the old so will be no issue and within tolerance

255/40R17 vs 255/35R18 : new tyre will be 0.02% smaller than the old so this setup shouldn't throw our your speedo

hope this helps!

 

[enuff_zed]

The diagram in the other thread you refer to is pretty accurate.
Your existing set up is the orange and the new set up is the green.
From that you can see there is hardly any difference in overall diameter and the tyre will project outwards a tiny amount more.
Overall, unless you are racing, worried about perfect suspension set up etc, then these will fit and look much better.

 

[yyz_bobby]

The diagram in the other thread you refer to is pretty accurate.
Your existing set up is the orange and the new set up is the green.
From that you can see there is hardly any difference in overall diameter and the tyre will project outwards a tiny amount more.
Overall, unless you are racing, worried about perfect suspension set up etc, then these will fit and look much better.

Great stuff.
No not racing for sure. Past that stage.

Looks like a good buy then

 

[yyz_bobby]

Hi all

Need some advice

Owned my z4 E85 for 3 weeks

Currently has OEM 17" alloys and run flats. same one in my avatar pic.

Current tyre setup is:
Front: 225/45/17 and Rear: 255/40/17

First Question - why would my front tyre have lower profile than my rear? Barely noticeable when looking but curious.

I have seen a nice set of alloys for sale 18" and I think once I have these and some non RFs that my ride will be massively improved however I am concerned about whether they will fit without me having to touch spacers (not sure what these are to be fair) and/or if I need to take into consideration anything else? Eg brakes, cambers, strut? Could any of these be negatively effected?

The 18" alloys take tyres of the following measurements:
Front: 235/40/18 Rear: 255/35/18

Q1 - here the front is wider
Q1 - the tyres have a lower profile which I expect but that combined with the increase in alloy size would that still look better than what i have now?

Sorry for hijacking this thread.

Bobby

tyre profile relates to a percentage measurement of the tyre width not a millimetre measurement. so in your case your front tyres are a 45% profile of the 225mm width and rears are a 40% profile of 255mm width. all comes down to overall rolling diameter. What you will find is if you punch those figures into https://tiresize.com/tyre-size-calculator/ the rolling diameter front and back will be identical (this is important when looking for new wheels/tyres with +/- 3% to ensure your speedometer isn't thrown out of calibration)

RE the new 18s

do a quick search on http://www.bmwstylewheels.com/Z/Z4-E85+ and look up the specs (offset + width etc) of your current wheels and compare to the new wheels.

e.g. if the new wheels are the same width as your current 17s but with a lower offset then these wheels will sit that much closer to the outside of your guards.

e.g. if stock is 17x8 +40 and the new wheel is 18x8 +30 then your new wheel will protrude 10mm further outwards.

I use this online calculator to make an educated guess if wheels will fit.

https://www.1010tires.com/Tools/Wheel-Offset-Calculator

answering your question:

225/45R17 vs 235/40R18 : new tyre will be 1.72% bigger than the old so will be no issue and within tolerance

255/40R17 vs 255/35R18 : new tyre will be 0.02% smaller than the old so this setup shouldn't throw our your speedo

hope this helps!

Great explanation mate, took me a few reads but I kind of get it.

Think I will get these now.

 

[AER]

I wanted a rim that was more stream-line and understated than the stock 18" 3.0 sport rims so I painted everything but the face of my new rims satin black. The 225/40/18 tire on the 8" 35ET front rims brought it out 18mm from the stock 47ET looks and fits nice. The 255/35/18 tire on the 9" 30ET rear rims has brought the rim out 26mm or 1.023 inches from the stock 50ET and is cutting it VERY tight. No way a 255/40/18 would fit in the fender well. I have yet to adjust the camber and I'm concerned it will rub after I do.

 

[yyz_bobby]

I wanted something a little bit more understated so I painted everything but the face satin black. The 8" front rims with a 35ET from the stock 47ET looks and fits nice. The 9" rear rims with a 30ET from the stock 50ET is cutting it a little to tight. No way a 255/40/18 would fit in the fender well and I have yet to correct the camber. I'm worried I will rub after the camber adjustment.

Looks good!

 

[CHIMV8]

Great info in this topic

 

[Bkbkbk84]

Looking at CSL reps today at BM and wanted to know if anyone has any input as to which of these between a rarer fitment of atomic’s or the Riva Dtm.. is there a better looking wheel in terms of finish etc? The atomics look brighter in colour and have the embossing etc.. slightly different specs but offsets seem to counteract width. Any thoughts? On a m sport suspension E86 coupe in carbon black..


Atomics-



NOW BACK IN STOCK!! (29/5/2020)

Brand new high quality light weight 19" staggered Atomic CSL alloys with deep concave rear finished stunning hyper silver. (SATIN GUNMETAL ALSO AVAILABLE IN OTHER ADS)

Very rare fitment with the et45 rear for a direct fit to the Earlier 3 series cars and Z3/4, even will go on a 1 series.

As you can see in the pics these have the correct spoke profile with even Concave from edge of wheel to centre to give them the best possible look

They are 19" x 8.5" et38 front and 19" x 9.5" et45 Deep centre rear



OR

Brand new 19" staggered Riva DTM CSL alloys with deep concave rear finished in silver.

These must be seen as look stunning.

They are 19" x 8" et34 front and 19" x 9" et37 Deep concave rear.


Any info is highly appreciated. Want to run a 35 tire on back to help with ride and filling arch on standard suspension..