21-10-2019, 07:11 AM
re Roland Alcocks comments,
I can only guess exactly why stiff tyres cause wander. Curiously, high pressure sharpens handling of moderns; radials now run near 10 psi higher then when first on the scene.
I wonder how Sevens on modern very flexible single wall ply tyres compare with the thick multi cotton ply original tyres when new. These were run at lower pressure than currently but were still mighty stiff. Late Edwardian and early vintage cars ran with small section multi ply cotton tyres at very high pressure. Possibly there were not sufficent fast sealed roads for handling on them to be a consideration.
Wrong toe in can introduce instability. It takes very little to distort the track rod.
(in modern times tyres had/have a ply rating but it is no longer the actual number of plies)
I can only guess exactly why stiff tyres cause wander. Curiously, high pressure sharpens handling of moderns; radials now run near 10 psi higher then when first on the scene.
I wonder how Sevens on modern very flexible single wall ply tyres compare with the thick multi cotton ply original tyres when new. These were run at lower pressure than currently but were still mighty stiff. Late Edwardian and early vintage cars ran with small section multi ply cotton tyres at very high pressure. Possibly there were not sufficent fast sealed roads for handling on them to be a consideration.
Wrong toe in can introduce instability. It takes very little to distort the track rod.
(in modern times tyres had/have a ply rating but it is no longer the actual number of plies)