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Discussion Starter · #1 · (Edited)
http://www.tirerack.com/tires/tires...urato+P7+with+Seal+Inside&partnum=345WR7CP7SS

I put 4 of these on the 2017. They fit fine, road noise minimal, they have curb protection, are LRR, and are self-sealing like the Bolt tires. They are a summer compound performance tire, but do have very deep rain grooves. This size is a bit wider when mounted than the 215 tires the car sells with, but not too big. Tire Rack suggests a 7.5" rim but they seem very good on the OEM 7.0" rim. Since I will be abusing these, I wanted more tread on the outside edges, I melted the stock fronts and rolled a little onto the sidewall.

They a 0.1" shorter per spec sheet, a 260 compound (legal for autoX, more grip than stock), and increase load rating about 500lb for the set and have a higher speed rating (W). They are rated for up to 51 psi instead of 44 psi. They spec at 3lb heavy though, or 12lb a set.

I will AutoX with them next weekend, check the effect on range, and if things don't change, I'll see how they do in the rain.

It's too hard to tell much about tires when fresh. So I need to break the surface to get good info.

Will report back. At this point? They fit and are not noisy.
 

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How's range on these tires?

Did you mount these yourself or was the tire shop willing to mount the tires for you despite the size difference?
 

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Discussion Starter · #3 ·
I pay about $15 a piece for mount and balance at my local shop. Your results may vary.

Concerning the size, per spec, they are 0.4" wider total. However with the rim protector lip, they appear wider at the rim, but looking at the back of the car with one of each on, you really can't tell much difference.

I will not know the range for awhile. I have a 58 mile roundtrip I take that I just make it back. I have a hunch that I will not make it based on the softer compound. But then again, I can run these 51psi cold, perhaps 55 psi if I want to extend range. Since they are not that much wider, the higher pressure might mitigate the softer compound and slight increase in weight and width.

We will see. The self sealing feature with a grippier tire is more in tune with how I drive.
 

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Glad to hear they're quieter than the OEM Michelins. I can't wait to wear my OEMs down so I can get the All-Season Cinturato P7 and enjoy silence...

Forgot to ask, did you actually use-up your OEM Michelins or did you offload them on someone else? If you wore them down, how many miles did you put on them before retiring them? You seem a sportier driver, so I'm thinking I'll need another 25% more miles than whatever you put on them before I can retire my OEM Michelins. I hear OEM tires are typically formulated to be softer and wear faster than tires you buy from tire shops...
 

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Discussion Starter · #5 ·
I only had 2500 mile on the OEM tires. I will probably sell them or put them back on when it's time to sell.
 

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Will be interesting to hear what you find. I'm assuming you'll lose some range, especially at first. Was there anything in particular you didn't like about the Michelins?
 

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Discussion Starter · #7 · (Edited)
Will be interesting to hear what you find. I'm assuming you'll lose some range, especially at first. Was there anything in particular you didn't like about the Michelins?
I'm teaching my son to AutoX using Volts. The OEM Michelin tires 'chunk' (pieces of tread block snap off) because the compound is too hard for violent cornering. These are 260, which is normal daily driver summer high performance traction.

Oh, and the OEM LRR's have had 4 flats in 4 years between 3 cars. It was self-sealing or runflat. I hate carrying a spare.
 

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Discussion Starter · #9 ·
hit me up when you want space in your garage and the tires gone
What year? I have both tires and also Gen 1 rims with TPMS in them. San Marcos is about 1 hr away.
 

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Discussion Starter · #10 ·
OK, first test. I have a 58 mile roundtrip to a customer that is ~75% freeway. My record in either a 2016 or 2017 Volt on OEM tires (60-65mph) is 13.2kWh.
On the new tires, first try, 13.6kWh. So there is probably some losses, but not huge amounts. They are LRR tires, and I do run them at max rated inflation of 51psi.
 

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Oooooh, your positive results are not helping my check book. Too tempting to upgrade now that range hit is minimal at high PSI.

I don't know what I'd do if you said, "ride quality at 51psi is same as OEMs at 36psi". I'd probably cave.
 

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Discussion Starter · #12 ·
Oooooh, your positive results are not helping my check book. Too tempting to upgrade now that range hit is minimal at high PSI.

I don't know what I'd do if you said, "ride quality at 51psi is same as OEMs at 36psi". I'd probably cave.
The best ride quality is about 32-36 psi. It will dramatically reduce your range. 51psi is harse.
 

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Can I assume ride quality can be approximated linearly w/r to tire pressure? So your range hit at 51psi was about 3%. I'll assume the adage from other Cinturato reviews on the forum that a range hit of 10% at OEM pressure (36psi). So for a 5% range hit I'll need 46psi.

Sounds reasonable. You wouldn't by any chance have any other data points at different psi, would you?
 

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Discussion Starter · #14 ·
Can I assume ride quality can be approximated linearly w/r to tire pressure? So your range hit at 51psi was about 3%. I'll assume the adage from other Cinturato reviews on the forum that a range hit of 10% at OEM pressure (36psi). So for a 5% range hit I'll need 46psi.

Sounds reasonable. You wouldn't by any chance have any other data points at different psi, would you?
Perhaps in the future. I'm putting another set on the 2016.
 

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Discussion Starter · #16 ·
Well, that did not take long.

My son was driving to school yesterday, 6 miles, and the tire pressure warning went off and read 28 PSI when he parked at school. Original pressure was 37psi last weekend. When he got out of school, the pressure warning was on, and the sensor said 30 psi, which is normal due to sunlight. When he got home, he told me about it. Uh... Should you have TOLD ME immediately???

So I go out and check, sure enough, the right front measured 30 psig with a gauge. I drove the car to work and checked it. 30 psi. Then I inflated all 4 to 48 psig last night. This morning, all 4 read 46-47. I drove to work again just now and the pressure was the same. I looked all over the tire for a nail, and could not find one. Did it fall out? I do not know.

So I cannot tell whether the self sealing kicked in or not. But I have a hunch that it did. Our 2013 picked up a nail? last year and within 4 miles I got a call from my daughter that she had a flat. Very small hole right in the belts leaked rapidly when I inflated it with 125 PSI compressor. It did not hold air. Plugging it fixed it, but I had to open the hole with the rasp to get the plug in.
 

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Interesting. I was skeptical that self-sealing really worked all that well. Question remains how long the self-sealing will hold. Are you supposed to bring it to a tire shop after it self-seals? I liken the self-seal to using a fix-a-flat: temporary and you still need a proper fix from a tire shop (assuming they take issue with cleaning all that fix-a-flat goop out).

Thanks for updating your experience with these tires. If that self-seal holds long enough and can be repaired at a tire shop, I may just remove my full-size spare as well when I upgrade to these quieter Pirelli tires.
 

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Discussion Starter · #18 ·
Interesting. I was skeptical that self-sealing really worked all that well. Question remains how long the self-sealing will hold. Are you supposed to bring it to a tire shop after it self-seals? I liken the self-seal to using a fix-a-flat: temporary and you still need a proper fix from a tire shop (assuming they take issue with cleaning all that fix-a-flat goop out).

Thanks for updating your experience with these tires. If that self-seal holds long enough and can be repaired at a tire shop, I may just remove my full-size spare as well when I upgrade to these quieter Pirelli tires.
Well, for now we are just going to drive it. I do not know if there was a puncture or not. At this point it's only been 27 hrs since he told me the pressure was low. But since we AutoX'd the previous weekend, I knew for a FACT the fronts were set at 37 and rears at 34. No tire loses 10lb in a week and lives long.
 

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Well, for now we are just going to drive it. I do not know if there was a puncture or not. At this point it's only been 27 hrs since he told me the pressure was low. But since we AutoX'd the previous weekend, I knew for a FACT the fronts were set at 37 and rears at 34. No tire loses 10lb in a week and lives long.
It could be a bad tire stem valve core. Did you try the old trick of putting a bit of water, aka spit, on the bare tire valve with the dust cap removed. If a bubble forms then you'll know the valve is leaking. I had one on my last vehicle, my tires and valve stems were about two years old. Tire shop took out the tire valve, replaced it, did not even charge me.
 

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I thought spit/water would not be enough. I always read soapy water was needed.
 
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