I've been running the bbr stage 4 80cc engine now for about almost 3 years! And I've only ever had to replace the clutch camshaft once and only replaced the spark plug once and one new chain an one sprocket ever the whole time that is great but recently my bike doesn't run right now because it has no spark so I bought a new stater magneto from you guys hopefully that fixes it. Other than that, I love the thing it ran great.