Keep them treated.
I got three years and about 50% tread wear before they dryrotted on me. On a car that doesn't just sit (about 35,000 miles during that period.)
It's funny you mention dry rot; I started to just give someone a rear tire I had hanging up, for a cycle I've had forever, and realized it was completely dryrotted and was almost 20 years old, lol. Never been mounted; I bought a different bike.
You used to never know when the tires you got were made; now it's a mandatory cast-in marking.
If your tires are 5 years older than the "born on" date, replace them.
If you bump a curb and the sidewall falls out, that's dryrot, lol.
I've found that tires from deep discount places like sams and costco sell 3rd rate tires; you're lucky if they can be balanced.
I've gotten great tires from Summit and Tire rack; they're always fresh, and always balance with minimal weight.
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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