Avon ACB10's - what pressure and how worn is "time to throw"

[sjtgeray]

I have a little R reg Saxo VTR and ran it for the first (my first at least) at RAF Woodbridge a couple of weeks ago on used 14 inch ACB10's.
Any suggestions as to what pressures i should run in them ?

Also they have now worn the central grooves down to the point where they are slicks (at least in the centre of the tyres). Anyone know how much more rubber is left at that point or should they be disposed of ?

many thanks
s

[LaurenceFrost]

If they have worn the centres of the tyre, you definitely ran them at too much pressure.

Tyre pressures heavily relate to the weight of the car. For something around the 1000kg mark, I'd be running a tyre around 28psi hot and seeing what happens with it from there.

Also, something to bear in mind with those tyres is that they are a crossply, and require a different setup to a radial tyre. Primarily, they need very little negative camber (if any).

[sjtgeray]

Thanks for that...i ran them at about 27 hot so i guessed about right. Should add that the tyres were worn before i started and guess they are quite soft compound (lots of grip tho !) so maybe they wont last long. Hmm, not sure how the camber setup is. The guy I got the car off ran the ACB10's, i thought they seemed to pull to the right whereas on road tyres it doesnt so maybe some twiddling required
s

[GC8]

Too low a pressure can also cause excessive centre wear, but its almost always overlooked by almost everyone.

[fergus]

GC8 said:

Too low a pressure can also cause excessive centre wear, but its almost always overlooked by almost everyone.

how?

[GC8]

By allowing the centre to 'extend' due to centrifugal force, where it would otherwise be held in check if the pressure was adequate.