I have a set of Yokohama Avids touring with about 40,000 miles on them and 4 years old. They have all developed hairline cracks on the sidewalls near the wheels. I would like opinions as to whether these hairline cracks are dangerous or just normal after several years of use. I have emailed Yokohama but not received a reply as yet. Always kept the pressure around 30 psi with max cold pressure listed at 35 psi.
So, is this normal and safe?
thanks