Castrol 10w50 Motorcycle 4T Synthetic Oil
Kenneth Moonitz
Oil. Possibly the most controversial topic in motorcycling—right up there with tire choice and “what’s the best bike.”
At the end of the day, it’s the lifeblood of your engine. It keeps everything spinning, shifting, and not turning into an expensive paperweight. Lubrication, cooling, smooth gear engagement—it does it all quietly in the background.
Castrol is what Triumph Motorcycles runs from the factory, and for good reason. My 2007 Speed Triple originally called for 15W-50, which nowadays in the U.S. is basically unicorn blood—good luck finding it consistently.
So I followed Triumph’s modern spec and switched to 10W-50.
70,000+ miles later… no complaints.
The bike still feels just as smooth, shifts clean, and hasn’t given me a single reason to second guess it. Oil filters are a whole different rabbit hole (we’ll get there), but as far as oil goes—Castrol has earned its spot in this bike.
We’ll keep the miles rolling and see how far it goes. 🤙
