I believe the solendoid opens up the pump during start up to ensure plenty of oil is injected straight away.

Blanking the PJ's is never a bad idea as the holes in them are so small they are prone to blocking, which inevitably leads to siezure at hign speed...
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball