Originally Posted by Brigstocksbobber
From the handbook:
Lubrication System Wet sump
Engine Oil Capacities:
Dry Fill 1.00 US gallons (3.8 liters)
Oil/Filter Change 0.89 US gallons (3.4 liters)
Oil Change Only 0.85 US gallons (3.2 liters)
This is straight out of certain website? albeit it's for the 2017 model bobber, I could not find the oil capacity in the manual provided with the bike.
So I stuck with the old method of keeping an eye on the filler glass window making sure I did not overfill.
Triumph Bonneville Bobber 2017
2017 Triumph Bonneville Bobber specifications, pictures, reviews and rating
Physical measures and capacities
Weight incl. oil, gas, etc: 228.0 kg (502.7 pounds)
Seat height: 690 mm (27.2 inches) If adjustable, lowest setting.
Overall height: 1,025 mm (40.4 inches)
Overall width: 800 mm (31.5 inches)
Wheelbase: 1,510 mm (59.4 inches)
Fuel capacity: 10.60 litres (2.80 gallons)
Oil capacity: 4.50 litres (0.30 quarts)
OMG I just found it in the service manual you are correct
The oil is sitting at the top of the dedicated mark on the edge of the window so I have put in the right amount, I didn't measure how much I had left in the bottle.