I am underway on what will likely be my last motorcycle project and two weeks ago a set of 1951 Comet cases and covers arrived from Australia. The Comet was originally delivered to Liverpool, so they have traveled a bit. Mal Hewitt bought them several years ago thinking he would build a Comet special, but his time has been otherwise occupied it seems. I will probably use this new thread to ask a few questions, and here is the first one. The crankcases at one time passed through the Horner's shop for some repair work on the main bearing bores, but I am puzzled by the spigots for the push rod tubes. They are threaded. Does this modification ring a bell for anyone? Perhaps some clever attempt at sealing?