Why does a motorcycle burn oil at high speed but not at low speed?

[DeSilas]

Motorcycle burns oil at high speed but not at low speed for the following reasons: Oil quality issues: Using poor quality or viscosity grade non-compliant engine oil. Low-quality engine oil can lead to increased wear, and engine oil with too low or too high viscosity will cause poor engine lubrication, increasing wear on piston rings and cylinder walls, reducing sealing performance, and resulting in oil burning. Excessive clearance: Excessive clearance between piston rings and cylinder walls, improper installation of piston rings, or poor sealing can cause oil on the cylinder walls to enter the combustion chamber, leading to oil burning. Additionally, poor sealing performance of valve seals, damage to the crankcase forced ventilation valve (PCV), or clogged crankcase ventilation ports causing excessive pressure in the crankcase can all result in oil entering the cylinder with crankcase gases and participating in combustion.