Reasons for Motorcycle Power Loss in High Temperatures
3 Answers
Power reduction, easy stalling, and difficulty starting are all reasons for motorcycle power loss in high temperatures. Below is an analysis of the reasons for motorcycle power loss in high temperatures: 1. Power reduction: For air-cooled motorcycles, prolonged riding can cause excessive engine temperature, leading to power reduction, which is called thermal decay. 2. Easy stalling and difficulty starting: The main reason for easy stalling lies in faults in the fuel supply system and electrical system. Prolonged riding can cause high engine temperatures, and the internal parts of the engine expand and contract with heat. If the valve clearance is too small, this problem will occur.
My old motorcycle tends to lose power when climbing hills on hot days. Last time, the mechanic checked a few things for me: the engine oil was too thin and couldn't provide sufficient lubrication, the piston rings were worn out allowing hot gases to leak into the cylinder, the cooling fins were completely clogged with mud, and bubbles formed in the fuel tank blocking the fuel line. The most dangerous issue was when the coolant boiled over and blew off the cap, causing the pressure to drop and the temperature gauge to go crazy! Now I've developed a habit of stopping every 150 kilometers on long summer trips to touch the engine cover—if it's too hot to handle, I find some shade and rest for half an hour. Cleaning the radiator should be as routine as brushing teeth—spray some cleaner on the fins every week and rinse them off. For air-cooled bikes, use a small brush and an air gun to blow dust off the cooling fins.
Motorcycle power loss under high temperatures is fundamentally caused by combustion environment instability. When cylinder head temperature exceeds 120°C, air density decreases resulting in over-rich air-fuel mixture that compromises explosive force. Simultaneously, high temperature disturbs ignition timing alignment, reducing combustion efficiency. Older vehicles require particular attention to failing fuel pump pulsation dampers - vapor lock in fuel lines can cause sudden fuel cutoff. Additionally, deformed carburetor float bowl gaskets under heat lead to uncontrolled fuel levels. During my 318 National Highway tests, I observed 24% power loss in high-altitude sunny conditions. The solution involves shortening maintenance intervals and upgrading to full-synthetic oil for enhanced shear resistance.
