Geralt said:
Ammmm.... just bought a Castrol GPS 10w40 with all the trimmings and adulations on the bottle. It says "for four stroke motorcycle engines", it has a motorcycle engine on it, it "said" to have newest technologies blablabla...
You guys scare me. What can be wrong with that?!
Read for yourself
Going strictly what the original poster said, they did not use this oil, they
used regular Castrol synthetic blend.
They specifically said they called Castrol and Castrol told them to use
the "motorcycle oil" synthetic blend.
That tells me they used regular off the shelf automobile oil... Not the motorcycle specific oil that you have listed here.
The oil you have listed here is probably fine.
