[alohasurftoad]

@ ET36 the 245/35/20 will fit but be close to the spring perch, like vitoco's. it will not rub during compression or at full-lock.

if you are rwd and still concerned about 245/35 front, consider 235/35/20 front 245/35/20 rear. this will surely have no issues. sorry, just re-read you have x-drive, disregard this...

this thread has more than a few running 245/35/20 front
https://f30.bimmerpost.com/forums/sh....php?t=1047084
.

[GamaM440]

Thanks a lot will see or maybe stay with OEM but they are expensive

QUOTE=alohasurftoad;30822535]@ ET36 the 245/35/20 will fit but be close to the spring perch, like vitoco's. it will not rub during compression or at full-lock.

if you are rwd and still concerned about 245/35 front, consider 235/35/20 front 245/35/20 rear. this will surely have no issues. sorry, just re-read you have x-drive, disregard this...

this thread has more than a few running 245/35/20 front
https://f30.bimmerpost.com/forums/sh....php?t=1047084
.[/QUOTE]

[GamaM440]

Originally Posted by alohasurftoad

@ ET36 the 245/35/20 will fit but be close to the spring perch, like vitoco's. it will not rub during compression or at full-lock.

if you are rwd and still concerned about 245/35 front, consider 235/35/20 front 245/35/20 rear. this will surely have no issues. sorry, just re-read you have x-drive, disregard this...

this thread has more than a few running 245/35/20 front
https://f30.bimmerpost.com/forums/sh....php?t=1047084
.

Ok I will chk 235/35 and 245/35 as you suggest , I will gain width in front and will loose width in rear , is this ok with performance factor.OR
I am thinking I am not gaining much by 245/30 to 245/35 , I do drive aggressive and do high speed runs on bending roads , roads are also not top notch here in Newfoundland Canada I will loose looks with 245/30 or I lower my ride, it's so much variables, I think I should stay with oem 225/35/20 and 255/30/20 and gain comfort via non run flat conti which will give me and vechle some comfort, I think so, anyway great help by you , I really appreciate, do you have any FB page where you contribute?
Thanks again

[GamaM440]

Originally Posted by GamaM440

Thanks a lot will see or maybe stay with OEM but they are expensive

QUOTE=alohasurftoad;30822535]@ ET36 the 245/35/20 will fit but be close to the spring perch, like vitoco's. it will not rub during compression or at full-lock.

if you are rwd and still concerned about 245/35 front, consider 235/35/20 front 245/35/20 rear. this will surely have no issues. sorry, just re-read you have x-drive, disregard this...

this thread has more than a few running 245/35/20 front
https://f30.bimmerpost.com/forums/sh....php?t=1047084
.

[/QUOTE]

Oh ok yes 235/35 snd 245/35 no for me as mine is xdrive , just saw your post

[GamaM440]

actually you know your both given sizes are not that bad please see attached file the difference between two is barely about 1% 1.03 and in one case 1.04% - what you say

Originally Posted by GamaM440

Thanks a lot will see or maybe stay with OEM but they are expensive

QUOTE=alohasurftoad;30822535]@ ET36 the 245/35/20 will fit but be close to the spring perch, like vitoco's. it will not rub during compression or at full-lock.

if you are rwd and still concerned about 245/35 front, consider 235/35/20 front 245/35/20 rear. this will surely have no issues. sorry, just re-read you have x-drive, disregard this...

this thread has more than a few running 245/35/20 front
https://f30.bimmerpost.com/forums/sh....php?t=1047084
.

[/QUOTE]

[GamaM440]

How Strick we need to follow xdrive 1% staggered rule please have a look on calculator file as this set up is slightly above 1% 1,03 and 1.04%
235/35/20 and 245/35/20
thanks

Originally Posted by johnung

Okay, I read a couple of your past posts to learn that you have a 435i XDrive convertible. So you have XDrive compatibility concerns with the spare tire diameter. Do you intend to put these new 235/45-18 DWS06+ on the stock 400M 18x8.0” wheels?.

First issue with a spare is if it will clear your brakes. Do you have Grey brakes or the larger Blue brakes? The product description says it’s an 18” wheel designed for brake clearance. That is a good sign but no guarantee until you test mount it.

There are a couple things that concern me (but may just need clarification) so you should send a message to the retailer:

1) Ask if the wheel is compatible with your BMW 435i? Their description lists 5-series.

2) Ask if the wheel has a 72.56mm center bore? The description already says that the lug pattern is 5x120mm, but you need to confirm the center bore for fitment.

3) Ask what the exact brand and model tire is? I’ll explain below.

The measured diameter of the 235/45-18 DWS06+ according to TireRack is 26.3” (up from the stock 26.0” diameter which is actually good for use with a compact spare) see photo.

The spare specs say that it’s tire diameter is 26.5”. I wasn’t sure whether to believe that so I looked up that spare size on TireRack. There are two that size from Continental and Kuhn that both measure at 26.5” diameter so it’s probably correct.

I had hoped that the Amazon tire would turn out to be one of those two brands which would confirm the 26.5” diameter. But the tire tread pattern on the Amazon tire doesn’t match either of the two TireRack spares. See photos. But advertised photos often don’t match shipping product, hence the third question.

So a 26.5” spare tire and your new 26.3” DWS06+ tires would work well together within the safety of the XDrive specification. Get those other questions answered though.

Hope this helps!

[alohasurftoad]

Originally Posted by GamaM440

actually you know your both given sizes are not that bad please see attached file the difference between two is barely about 1% 1.03 and in one case 1.04% - what you say

[/QUOTE]

1.03-.04% would probably work, especially since i've seen some OEM tire size combinations as high as 1.2% on some 5-series. OEM 20" tire size combinations on 5-series x-drive with 245/35/20+275/30/20

[GamaM440]

ok thanks to you as you found this combo

1.03-.04% would probably work, especially since i've seen some OEM tire size combinations as high as 1.2% on some 5-series. OEM 20" tire size combinations on 5-series x-drive with 245/35/20+275/30/20[/QUOTE]

[GamaM440]

Hay Buddy

Just wondering if I put 250/30/20 all around . how my front 8" wheel will behave as 8" ideally recommended to max 245mm , I mean wear tear of tire and suspension and xdrive and performance in corners and high speed runs ?
Thanks

1.03-.04% would probably work, especially since i've seen some OEM tire size combinations as high as 1.2% on some 5-series. OEM 20" tire size combinations on 5-series x-drive with 245/35/20+275/30/20[/QUOTE]

[GamaM440]

1.03-.04% would probably work, especially since i've seen some OEM tire size combinations as high as 1.2% on some 5-series. OEM 20" tire size combinations on 5-series x-drive with 245/35/20+275/30/20[/QUOTE]


Hay Buddy

Just wondering if I put 250/30/20 all around . how my front 8" wheel will behave as 8" ideally recommended to max 245mm , I mean wear tear of tire and suspension and xdrive and performance in corners and high speed runs ?
Thanks

[alohasurftoad]

Just wondering if I put 250/30/20 all around . how my front 8" wheel will behave as 8" ideally recommended to max 245mm , I mean wear tear of tire and suspension and xdrive and performance in corners and high speed runs ?
Thanks

when you pinch a wider tire on a narrower than recommended rim, sidewall support is lessened and the tire perform less than optimally during performance driving. during normal daily driving you would probably not notice. i have seen a few people pinch on rims narrower than spec, here on the forum. personally that's not how i'd roll since the spec was set for a reason. i'd rather just run the OEM sizes...225/35/20 on 8" and 255/30/20 on 8.5.

[GamaM440]

Thanks make sense , and just notice 250/30/20 won't exist or not available

Originally Posted by alohasurftoad

when you pinch a wider tire on a narrower than recommended rim, sidewall support is lessened and the tire perform less than optimally during performance driving. during normal daily driving you would probably not notice. i have seen a few people pinch on rims narrower than spec, here on the forum. personally that's not how i'd roll since the spec was set for a reason. i'd rather just run the OEM sizes...225/35/20 on 8" and 255/30/20 on 8.5.

[alohasurftoad]

Originally Posted by GamaM440

Thanks make sense , and just notice 250/30/20 won't exist or not available

yes no such a thing as 250. every tire is xx5. 185-225-245-255-305, etc

[MagnusAG99]

There is a Norwegian online calculator that does this. It compares two tire sizes. https://dekkalkulator.com/

[Lada-1]

Originally Posted by MagnusAG99

There is a Norwegian online calculator that does this. It compares two tire sizes. https://dekkalkulator.com/

not 100% correct calc

[MagnusAG99]

Originally Posted by Lada-1

not 100% correct calc

Better than nothing lol

[visionaut]

Wheel & Tire Calculators have their place.

They are 100% accurate with wheels info (diameter/width/offset) comparisons. But they use only manufacturing “standard-based’ data for tire size info.

To get 100% accurate for tires info, you have to use a specific tire’s data from a specific manufacturer, like you can find at tire sites like Tire Rack (which can vary slightly from the standard, which uses minimum/maximum type specs). So unlike a 19x9 et30 spec wheel, a 255/35-19 spec tire from different manufacturers will not be exactly the same.

So use the calculator for exact wheel diffs, and ‘first-pass’ wheel+tire fitment difference calcs, but supplement the latter calculations with the exact tire spec info to be 100% wheel+tire accurate.

I use and recommend WillTheyFit.com because I like its design.
https://www.willtheyfit.com

[Lada-1]

Originally Posted by visionaut

To get 100% accurate for tires info, you have to use a specific tire’s data from a specific manufacturer, like you can find at tire sites like Tire Rack

Could you please provide the exact link to a tire e.g. PS4 255/40/18

[visionaut]

Originally Posted by Lada-1

Could you please provide the exact link to a tire e.g. PS4 255/40/18

Sure. You’re looking for the Tire Specs section… it’ll list exact values for THAT specific brand/model/size tire.

https://www.tirerack.com/tires/tires...um=54YR8PS4SXL

Screenshot:

[visionaut]

…so the calculator says ‘std’ diameter is 661.2mm [math = ((255*.40)*2) + (18 *25.4)], whereas this exact model Michelin is 660.4mm diameter [26.0*25.4].

And instead of 255mm ‘std’ spec section width this exact tire has a 259.1mm section width [10.2*25.4].

From this you can see the PS4S in that size is very close but slightly shorter in height, though from an fitment POV, the 4mm-wider section width (2mm/side) than the ‘standard’ spec might be more meaningful…