Designed to fit push rod Nortons fitted with the later alloy heads, this inspection cover allows fitting of a breather. A breather in the rocker box will help to reduce oil leaks from the top end of the engine and the push rod tubes, as well as reduced oil being forced down past the valve guides to be burnt.
 
Manufactured in LM25 aluminium. The set comes complete with a banjo and bolt to accept a piece of 8mm (5/16'') pipe (not supplied).
 
We also do breathers for the earlier rocker boxes as fitted Post 48 cast iron head.