Just bought a used V10 and ......

have a couple of questions.
Q1. my old spec skis and my Red7Surf70 have breather tubes and/or a bung. i guess it isn't needed, so how come my other boats have them?

Q2. My latest toy is missing the cover over the rudder yoke so I will peobably make one. however, there isn't any way that i can see to fix a plate. no internal threads or studs. do the covers get siliconed on?

must be a really old v10???

Yep. its an old one. South African built. what drew you to that conclusion?

The current V10's have a siliconed plastic fitting set into the rudder recession. This fitting has the thread where the screw-on cover fits. Initial hassles here were that the plastic fitting was not siliconed adequately (choice of material used?) hence came loose. Chances were that it happened out at sea where you flip over a wave and it would get flicked away, never to be found.

My old SA V10 had a rectangular carbon cover held in place by a single screw that went throught the cover and into the ski to meet a raised area under the cover.

Newer v10 have a circular plastic cover that screws in.