flyingmm mine is six years old, it’s had an oil change each year and one change of sprocket and chain and done 2 years road commuting and 4 years off road commuting all year round. At the moment my bike gets plastered in mud twice a day and I couldn’t be using something that needs cleaning for it to work. You can get the oil in 250ml bottles now which makes it more economical, it’s worth checking the German web sites for the best price.