The Honda SOHC4 forum has folks on it that restore old Hondas to "factory correct" and they will spend a lot of money on original and authentic. And this includes the exact correct tire that was shipped on that year.
I rode up to this past Dragon with a guy named Bill that took a beater 550 honda four all the way back to "factory correct" and the bike now sits on a dealer's showroom floor next to the offices as a very pretty floor ornament.
Many many man hours spent searching out parts, and he admits he has more in the restoration than the original bike cost new.
Some folks get off on that stuff, us, we tend to ride our Savages.
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There is a legal age limit on tires of 3 years, you can't sell them at retail past that point. Say add 2-3 years to that to get you a recommended max useage life ..... what 5-6 years total? Not really stated as such, but some use it as a rule of thumb just like a tire was a jug of milk or something.
If you were tubeless, you would not be able to get a tire that is severely age cracked to hold air very well.
However, our tires are tube type tires and the tube holds in the air so we have heard periodically about some very age cracked tires being used up by some folks.
The gripping rubber ages like the cracked sidewall rubber, so you can expect an age cracked tire to be somewhat reduced in wet gripping force and cornering force. You don't see cracks on the thread portion as the rubber is constantly wearing off the tire (cracks never have a chance to form on the tread).
Old "expired out of date" tires do increase your wet weather and cornering risks in some vague fashion.
HOWEVER, anyone who has actually worn out a Metzler ME 880 H series front tire has likely been riding for YEARS and YEARS and years on a technically out of date tire (yup, they last that durn long).
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Reality here on the list We oldtimers snap up them good Motorcycle Superstore 3 year "age out" sales all the time on bike tires. I bought multiples last time when a really good sale came by on rear tires and the last one left from that buy was like 6 years old when it came out of the AC'd upper closet and went on a bike.
It looked new on the side walls when it came off the bike a year and a half later.
But it was stored correctly all those years (tires like the same temperatures that you do).
Reality here on the list is we tend ride those old tires until the tread is plum gone ....
Reality is ....
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