02-20-2021, 10:54 AM | #1 |
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Conventional Low-Profile Tire Question
hey boys and girls,
so i was thinking of replacing the run-flat tires on my car with the 20" wheels with low-profile conventional tires in an effort to reduce tire noise within the cabin and also to refine the ride as it's not the most comfortable. is this a good idea, or would i be wasting money buying tires for nothing? if it's a good idea, i.e. if you've done it before, which tires do you recommend? i don't want something with super large sidewalls because it just won't look good, so i'm trying to find that balance between aesthetics, noise reduction and comfort. thanks!
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02-20-2021, 11:19 AM | #2 |
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A tried and true option for sure and one I've used time and again on my bimmers (see my signature). I never stay stock size when I replace tires. I've even replaced brand new stock tires using this approach.
Typically, I have upsized the tire by 1 or 2 sizes and ditched the run flat. This gives you more cornering grip plus a bit more rim protection both from curbs as well as from potholes (a big issue here in Chicago metro). For the X2 with 20" rims that strategy would be 235/40-20 or 235/40-20. However, 235-40 has very few tires available. Tire rack will show you noise vs grip tradeoffs for each tire. 245/40-20 opens things up a bit and gives you a lot more options. You can't really go larger than 245/40 because a 255/40 doesn't fit an 8" width wheel. Both of these will change your actual vs indicated speed very slightly and interestingly towards a more accurate reading. Here's why. The indicated speed and the actual speed is intentionally different on most European cars. You may have seen the term 'corrected speed'. As an example your speedometer will read 60 mph but in reality you are traveling 58. Try it by setting your cruise and then reading actual with google maps. So what this means is that when you increase the diameter of your tire slightly by upsizing, your speedometer, which measures revolutions on your wheel, will be closer to accurate than stock (1 revolution will travel farther with a upsized tire). Hope this helps and makes sense.
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Last edited by Pyrat 2; 02-20-2021 at 07:21 PM.. |
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Davy Jordi106.00 tesmithp4.50 |
02-20-2021, 01:35 PM | #3 |
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I did the same sort of on my F33, stock was 225/40/19 and I went to 235/40/19.
When I ditch the runflats on my X2 I will replace the 225/45/19 with 235/40/19 or 245/40/19 |
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Davy Jordi106.00 |
02-20-2021, 03:44 PM | #4 |
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Thanks for the information, guys -- very informative and much appreciated! I think I'm going to ditch the run-flats because they are pretty bad.
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02-20-2021, 04:48 PM | #5 |
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I kind of wish I had my runflats last night.. coming home really late from work in a snow storm.. I hit a pothole and lost immediate tire pressure just 5 miles from home. Limped it straight away to a parking lot and waited 1.5 hrs for a tow.. poop.
I have the stock 19's back on and they are noisier and harder than my winter tires. I really might have to look into the spare tire kit, I would have had to swap the back to the front, of course that's in hindsight. Usually the tow comes within 30 minutes. Also side note.. an icy tow truck bed was no match for the Xdrive, the car drove straight up without having to hook up the front tow hook (although I popped the cover and put it on ahead of time). |
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02-20-2021, 09:27 PM | #6 |
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This was in December on my F33. Had a flat on the freeway and had to exit into the ghetto (where we just helped that department with a shooting) and I’m sitting there waiting for my daughter to bring me my all season setup and a jack. Changed one just to get out of the bad area and the car was shaking like crazy so I pulled over and turned off xdrive with xdelete and it drove better but we changed the other wheel just to be safe. Wish I had runflats then.
Mismatched wheels. |
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02-21-2021, 09:27 AM | #8 |
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Nope.. one guy trnguyen? Found a mercedes spare wheel that fit though.. it's starting to make me really reconsider what I might buy after that fun night. Although I haven't had a flat like that in over 15+ years.
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02-23-2021, 12:09 AM | #9 |
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I'm planning to swap out the run-flats with Micheline Pilot Sport 4S in 235/40/20. Should be quieter, more comfortable, yet perform better and last longer. The optimistic speedo bugs me so this would help with that as well.
Probably pickup a single OEM 20" wheel to keep as spare at home, and take it on road trips. This setup worked out well for wife's previous Audi where it came with non-run-flats but no spare. |
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02-23-2021, 03:35 AM | #10 |
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I’m looking at one of the Michelin CrossClimate tires in 235/45/19. Anyone have any experience with these?
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02-23-2021, 08:02 AM | #11 | |
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Quote:
I haven't got a flat to use it, but the potholes season has not started yet here, but soon. |
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