[alexk0il]

Just swapped my Pirelli Cinturato SF2 All Seasons to summer tires and noticed that the inner surface of Pirellis is uneven with some kind of bulging.

Never seen this before, all four wheels are affected though not to the same degree. No visible bulges on the outer side.

The tires are ~5 months old with roughly 5K miles on them, they look like new outside.

Is this normal? Shall I contact the shop/manufacturer?

 

[SimonRoma]

Blimey, no I do not think that is normal mate, I would contact the tyre fitter AND the manufacturer with photos straight away!!!

 

[thesmileyone]

It's called castling I think, my s3 tyres made a right racket from it.

 

[SimonRoma]

And ps consider this: tyres dont really like being changed so consider purchasing a spare set of wheels to host your winter tyres so then you just swap the wheels and NOT the tyres.

 

[alexk0il]

Got the official reply from the shop:

"It is believed that the bulges seen in the images on the inside of the tyre are the joints on what is known as the green casing (This is the tyre constructed with the steel belts and tread rubber before curing in the mould).

When the tread rubber is put on the tyre casing before being cured in a mould, the two ends of the rubber meet and can sometimes create the visible join on the inner liner. This is not a manufacture fault and will still be suitable for the wheels again when required during winter."

 

[alexk0il]

And ps consider this: tyres dont really like being changed so consider purchasing a spare set of wheels to host your winter tyres so then you just swap the wheels and NOT the tyres.

I actually was thinking about that, problem is that I also want to change from 19" to 18" rims at the same time, this would mean two new wheelsets and two new sets of tires, which is definitely not cheap. I guess I will keep swapping tires till they die and downsize later.