General Altimax RT43 sucks. I hate them. Not sure why anyone would recommend that trash.
195/65R15 shortage?
- Thread starter eljefino
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KU27 has some squiggly sipes, though IDK how far down they're cut. Primewell looks like a summer only tire (though I would and do run separate snow tires.)
I got some "supermax" tires that flat spot like you wouldn't believe, so I'm ok paying more for a real brand name.
I got some "supermax" tires that flat spot like you wouldn't believe, so I'm ok paying more for a real brand name.
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Primewell (made by Giti... aka GT Radial) and Ohtsu (made by Sumitomo) are low-tier brands famous for selling tires designed and marketed as summer-only in overseas markets, in the US as "all seasons." Since there's no legitimate benchmark for labeling a tire all season, they can do this. I don't remember hearing many complaints about the KU27 in its former life, as it was a popular tire and many people repurchased it and were unhappy when it was discontinued. I will also caution that the classical thinking of disappearing sipes doesn't always hold true. Many people swear by Michelins that at half wear have almost zero siping, and my Cinturato P7 A/S Plus set has virtually all of the siping still in place at 7/32 but they have virtually zero traction. I run them in summer only and have to really take it easy on wet pavement.
There is M+S, which is a geometric definition based on the tread. Some summer-only tires have tread that meets the M+S standard, such as the BF Goodrich Comp2.
If those Ohtsu and GT Radial tires have M+S tread, they can wear the M+S label.
However, you're right that M+S doesn't mean anything about actually being all-season, and summer tires that say M+S can still have a glass transition temperature and start cracking at low temps. How are those low-tier all-season tires in cold temperatures?
Good to know.I put them on my Camry and they were really lousy. Not really good at anything and they wear really fast. But it also only gets city miles so
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REALLY interesting mini rabbit hole you sent me down. My years selling tires taught me that the M+S designation was more or less dictated by the tire manufacturer and not independently tested, but it seems like M+S and "All Season" are terms that simply get conflagrated often. M+S seems to have a legitimate physical requirement, though it doesn't really have anything to do with the tire's capabilities. I wonder if the RMA actually certifies every tire available for sale, especially the flash-in-the-pan bulk buy tires from overseas that show up, sell out, then disappear from the planet (Chinese-based companies often register a brand name, make a run of low end tires without a real care as to quality, then abandon the name and design after the production run is over... I've never been sure if this is a liability shield, because the molds are cheaply made and wear out quickly, both, or something else). I suppose I was more talking about "all season" marketing, which legitimately doesn't have a definable meaning and doesn't necessarily appear on the tire. I have actually seen overseas websites for Giti and Ohtsu tires with "Summer Only" designated in the marketing materials, while the same tire model is sold here with "All Season" in the marketing material. It's a scientifically meaningless term. But I'm really happy to have some clarification that M+S actually has a technical definition from the RMA, unhelpful as it is at determining actual foul weather traction.There is M+S, which is a geometric definition based on the tread. Some summer-only tires have tread that meets the M+S standard, such as the BF Goodrich Comp2.
If those Ohtsu and GT Radial tires have M+S tread, they can wear the M+S label.
However, you're right that M+S doesn't mean anything about actually being all-season, and summer tires that say M+S can still have a glass transition temperature and start cracking at low temps. How are those low-tier all-season tires in cold temperatures?
The MS designation stems from a time when radial tires were first introduced to the US public. It became obvious that radial tires had more grip than bias tires and could be made such that the snow (and mud) traction could be as good as some bias ply snow tires. The California Highway Patrol needed a way to tell which tires were good enough for conditions where snow tires were required. So the Rubber Manufacturers Association (RMA, now called the US Tire Manufacturers Association - USTMA) came up with a definition that involved the way the tread pattern looked, because snow traction tire testing hadn't progressed far enough to be reliable. It was better than nothing, but it did result in tires that had better snow traction than tires that couldn't meet the definition.
And tire testing: It's all done by the tire manufacturers or for them. If the government wants to know if a tire passes a test, the manufacturer has to supply the data. There are severe penalties if the tire fails. And that includes the MS marking.
BTW, the MS marking can include any of a number of symbols between the letters: +, /, -, etc. It's that marking that allows a manufacturer to call a tire an "All Season".