Gearbox

I stripped a motor a while ago and took no notice of the gearbox condition as it was been replaced as part of a complete rebuild and changes. I do remember the gearbox oil was not great, very black and sludgy. The bike was an unknown in respect if servicing etc, but wasnt in good shape in many aspects.
Cut to the chase the g/b was an Italian LI150 and was wrapped, boxed and put in shelf. Fast forward i need an LI box so got it out and started to clean up. No chips, cogs good BUT showing signs of overheating/blueing. Cluster seems okay. Never come across this before, should i chuck it.... If so see wanted section!
Cut to the chase the g/b was an Italian LI150 and was wrapped, boxed and put in shelf. Fast forward i need an LI box so got it out and started to clean up. No chips, cogs good BUT showing signs of overheating/blueing. Cluster seems okay. Never come across this before, should i chuck it.... If so see wanted section!