Originally Posted by
Chombi
I'm aware of the joint insulating materials that manufacturers added to later 80's/Early 90's Al lugged CF bikes, but I'm wondering if the insulation extends to the face of the ends of the CF tubes, where the CF and Al materials might still contact each other, which might explain the corrosion still occuring at the lug/tube seams of these bikes.
The aluminum lugs have ribs to provide glue clearance. The fiberglass sleeve slips over these ribs, and once in place there is no contact between the lug and the tube; just glue. That actually is one of the contributing factors to the joint flexing that cracks the paint there.