Amp rating of Red Earth Wire

Can anyone advise on the amp rating I need to replace the red wires from the battery to the earthing point on the frame of an 850 Commando ? Electrics are not really my thing but I guess I'll have to learn now. Don't know how it happened; just cut out, a small wisp of blue smoke from the wiring ......but the battery had tilted over? The other wires in harness look to be OK. Any help would be appreciated.

For a main battery connection I suggest you use a cable of at least 28/0.30mm (17.5A, standard) or, 32/0.020mm (16.5A, thinwall).

http://www.vehicle-wiring-products.eu/V ... dcable.php
http://www.vehicle-wiring-products.eu/V ... inwall.php

Thanks LAB.