Using the Spirit Level, the photo shows 9.9 degrees of caster (90 degrees less 80.1 degrees) whereas it should be somewhere between 4 and 6 degrees.

So the solution is to put a small wedge between the spring and the axle to reduce the caster angle.

A little bit of school boy maths such as 5 degrees of the circumference e.g. (∏* Radius * 2)/360 *5 = a wedge of 4.8mm.

Stacks Image 10614

Actually this was made a lot easier by my friend Loft saying that he could get a few wedges made that were 5mm thick!

So thanks to my iPhone and Loft, the Amilcar now goes round corners.

Stacks Image 10619

This solution won’t apply to all cars as in more modern classics the caster angle is basically fixed by the Macpherson strut but if you’ve got cart springs and they’ve settled over the years you should check this out.

Now, isn’t that a good enough reason to put an iPhone on your Christmas present list….

Background Photograph taken on AC rally in Ireland, 2010

Correcting your caster angle by phone -2