When I was a Jag' Mechanic, I used an electric wheel balancer, We had a lot of trouble with new tyres, They were not round !!, It was funny to see them get to a certain speed before they went into a big wobble, No amount of weights could stop the trouble on the road, You could get them better, But not good enough. Like he says, Everything has to be right, Or wrong in our case !!. Cheers Bill.
Great point, Bill-
You triggered a memory from the '70s, when I worked for the US Lotus importer, that was the Europa era.
We had problems eliminating an over the road suspension vibration issue, which varied from mild to quite severe.
A dynamic tire balancer was always used to repeatable perfection, but with less than perfect (unacceptable) road test results.
The issue was put down to the weight of the body vs the weight of the suspension, sprung vs unsprung weight, by comparison the suspension weighed too much.
I think the Special weighed in at around 1700 lb. (as comparison a caddie of the era was around 5000 lbs)
We ended up using a tire lathe; the car would be road tested to warm the tires, driven back into the shop bay, front end jacked up, lathe rolled under, and the tires cut.
Rubber scrap from a tire truing ranged from enough to hold in your palm to enough to fill a bushel basket, a truely impressive range.
The tires were then rebalanced, and problem solved. (I believe the tires were Japanese Dunlops)
Two thoughts I recall having back then- did caddie dealers even bother to balance tires and, what did Lotus owners do when they got new tires, I don't recall ever finding a tire lathe at the local tire stores.
But bottom line, as you say, is that tires are definitely not all round, and worth checking.
Best-
George