Thunderbird 1600 Synthetic Oil ?

A proper dedicated motorcycle oil - synthetic, semi synth or mineral - is designed to work with a wet clutch. Do not be tempted to use ordinary motor (car) oil as it will cause clutch slip because it is not designed to work with a wet clutch.

 

I have a T-Bird Commander (1700 cc) and I only use Castrol Power 1 Racing 4T full synthetic oil. The price is ridiculous (~$11.00 per quart in the US) because it has a picture of a motorcycle on the bottle, but it meets the specifications outlined by Triumph. This is what my owner manual calls for:

"Semi or fully synthetic 10W/40 or 10W/50 motorcycle engine oil which meets specification API SH (or higher) and JASO MA, such as Castrol Power 1 Racing 4T 10W-40 (fully synthetic) engine oil, sold as Castrol Power RS Racing 4T 10W-40 (fully synthetic) in some countries"

 

I am using Castrol 10/40 4T synthetic only because that is what the owners manual calls for (even has Castrol sticker on engine from Factory)