21" MPSS mystery leak and barcode shenanigans

[Mexecutioner]

For the past 3 or 4 weeks the front driver side tire had been losing pressure at a rate of about 1.5-2.0psi per week. Not having time to go to the tire place I pumped air over the weekend a couple of times and visually inspected the tire to the best of my ability trying to find a nail or some damage that would cause the slow leak.

I did have one tiny nail in the rear driver side one a month ago (after not even 2 weeks of replacing the tires) so I was thinking I picked up another one somewhere.

I finally had time to go t the shop where the wheel was removed and submerged for inspection and we found no bubbles after long testing. I insisted to check again as I was 100% sure it had a leak so the tech inflated it at high pressure (86 psi, which I though was nuts) and submerged it again. This time we saw bubbles coming out on the inside of the tire right where the tire meets the wheel. The tech marked the spot and told me: “I bet that is where the barcode is”.

He unmounted the tire and the barcode was exactly where he had marked it. He mentioned he has seen this before. This tiny white barcode allows the air to come out really slowly in some instances depending on where they place it at the factory. We inspected the wheel for irregularities and the surface was flawless.

He then proceeded, with the judicious use of a torch, to burn the barcode off and later he gently resurfaced the area and mounted the tire back on.

So far it seems the problem has disappeared, as the pressure has not dropped in the past days. It must be a rare occurrence, as the other 3 tires seemed fine, but still wanted to pass this information along. Kinda crazy to find this in tires of this price. Maybe I got a dud.

I hope this helps those of you with the 21” MPSS in the event you experience a mystery leak with no nails or punctures in sight.

[r33_RGSport]

Great info.
That is really something, a simple barcode causing a bunch of headache.
Glad they got it sorted out for you.

[Mexecutioner]

Yeah, crazy. I have a couple spares at home, one of them unmounted. When I get a chance I will snap a photo of the barcode and post it here.

[FourDoor]

Chalk that one up to one of those stories where I would have looked at the tire shop guy all funny if he told me a bar code label can cause a slow leak on a tire until now.

Great info and glad you were able to get it sorted!

[P1]

Thanks for your diligence here. Is that just a one-off issue, or do you think that could affect other MPSS tires also?

[Mexecutioner]

Originally Posted by P1et

Thanks for your diligence here. Is that just a one-off issue, or do you think that could affect other MPSS tires also?

I think it is a rare occurrence, maybe the barcode on that particular tire was slightly off position, maybe there was some substance between the tire and the wheel where the barcode was located, or maybe it was bad luck. The other 3 tires do not lose any pressure at all and have been consistent for months.

The tire guy had seen it before and knew exactly what it was so I am not the only one, but he did mention it's uncommon.

Whenever it's time to get a new set I may request for them to remove the barcode before installation, whether it is the MPSS or the PS4S, but that may be overkill.

[P1]

Originally Posted by Mexecutioner

I think it is a rare occurrence, maybe the barcode on that particular tire was slightly off position, maybe there was some substance between the tire and the wheel where the barcode was located, or maybe it was bad luck. The other 3 tires do not lose any pressure at all and have been consistent for months.

The tire guy had seen it before and knew exactly what it was so I am not the only one, but he did mention it's uncommon.

Whenever it's time to get a new set I may request for them to remove the barcode before installation, whether it is the MPSS or the PS4S, but that may be overkill.

It certainly is good to know. All four of my MPSS tires have been solid so far, and I haven't noticed any issues. Just one nail so far, but the plug is holding very well. Just like you, I keep a spare (rear) tire, just in case.