If the Sprint Classic is no longer approved for vehicles manufactured since 1990 that might be an issue
IF
- you were to have an accident
AND
- it was not the fault of a third party
And
- it was not your fault (due care and attention, speeding, etc)
AND
- the accident was serious enough to warrant inspection of the vehicle including the tyres
AND
- the tyres could be shown to be at fault and the proximate cause of the accident (as opposed to any other factor such as excessinve speed, poor weather, etc)
AND
- it could be demonstrated that this was a fault of construction rather than maintenance (under/over inflation, lack of tread, aged rubber etc)
THEN
- you could find yourself without insurance cover.
So a very low probability risk, but one with a high impact if it occurs.
Not an issue for my 1986 car, fortunately...