11-25-2022, 02:53 AM | #1 |
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Bmw F36 420xd stuttering with winter tyres
Featured on BIMMERPOST.com Can anybody please give me some answers?Thanks! |
11-25-2022, 05:20 AM | #2 | |
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If on 8" rims, difficult to say what is going on (assuming xDrive transfer tolerances), except pressure variation (F to R) possibly too great. On 8"/8.5" rims, could be pushing the RC tolerances. I'm assuming all tyres are the same brand, type and spec. |
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11-25-2022, 06:33 AM | #3 | ||
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What Rc tolerances means? |
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11-25-2022, 07:40 AM | #4 | |
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Having the same tires on different width rims is going to stretch/pull the tires harder on the wider rims, which may affect RC. |
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11-25-2022, 07:42 AM | #5 | ||
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And whats the recommended tyre pressure for those dimensions? |
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11-25-2022, 08:53 AM | #6 | |
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I'm assuming you are not using approved 'star' marked tyres. This can be the issue. Although generic tyres are to the correct dimension spec', doesn't mean they are all toleranced the same as approved tyres. Some examples of xDrive are more sensitive to tyre tolerances than other examples. Same as some staggered tyres work fine with xDrive, other staggered examples don't work well with non-approved tyres If your example is showing issues with a square setup, on mixed rim widths, to me that possibly indicates a sensitive or worn transfer box. |
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11-25-2022, 09:06 AM | #7 | |
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Saying that, some users do get away with that fitment. I do sense it can be a gamble, "some do, some don't", apples. |
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11-26-2022, 12:25 PM | #8 | ||
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11-26-2022, 02:38 PM | #9 |
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You might have something as simple as unbalanced or damaged wheels/tires on your winters. Describe the ‘stuttering’ you’re feeling better, and when it’s most noticeable.
Running same brand & tread-wear 225/45-18 tires all around on the mildly-staggered 8” fronts and 8.5” rears won’t come anywhere near being a problem with diameter/circumference differences for X-drive. You’d need to stretch the 225/45-18 out to almost 2” wider, on a 10” wide wheel vs stock 8” wide, to exceed a 1% diameter difference due to tire sidewall height shortening from the stretch. So I doubt with four new tires it’s that… The 8.5” wheels should still get mounted in the rear tho’. |
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