05-08-18, 12:11 PM
It's not a silly question 
First of all what's the recommended oil for your bike? If it's semi synth then go ahead. Semi synth is a mix of fully synth and mineral oil. All semi synth bikes may benefit from using fully synth but definitely not mineral oil. All you would be doing is increasing the amount of fully synth in the mix if that makes sense. Just make sure the oils are the same weight and viscosity (e.g. 10w40), So you should have no problems with the castrol.
First of all what's the recommended oil for your bike? If it's semi synth then go ahead. Semi synth is a mix of fully synth and mineral oil. All semi synth bikes may benefit from using fully synth but definitely not mineral oil. All you would be doing is increasing the amount of fully synth in the mix if that makes sense. Just make sure the oils are the same weight and viscosity (e.g. 10w40), So you should have no problems with the castrol.
Treat everything in life the way a dog would- if you can't eat it or foc it, forget it.