Hi Lou,

The most common cause of disc burn out is a varnished (insulated) cylinder from running a lot of castor. when the Norvell .060 (6X4's) 18 to 19000 Rpm came out we started getting calls on excessive burn out which we attributed much higher power then TD's so we added an aluminum disc then teflon and the problem when away. The discs can be cut from pop can's.

Bob Davis
Davis Diesel