Why does the motorcycle stall when shifting gears?
2 Answers
Here are the reasons why a motorcycle stalls when shifting gears: Side stand safety switch issue: For motorcycles equipped with a side stand safety switch, the engine will stall when shifting gears if the stand is deployed. Clutch problem: If the motorcycle starts normally in neutral but stalls when shifting into gear, it may be due to the clutch not fully disengaging. At idle speed, the engine cannot handle the load of the motorcycle's mass before the throttle is applied. Engine oil issue: Using low-quality engine oil in summer and leaving the motorcycle unused for half a year may cause stalling when shifting gears in winter. Poor-quality oil thickens significantly as temperatures drop, preventing the clutch from disengaging properly.
I've encountered this issue several times. Stalling when shifting gears is mostly related to the clutch. If the clutch cable is too tight or improperly adjusted, the engine and wheels become directly and rigidly connected when shifting, which will definitely cause the engine to stall. Another possibility is that the idle speed is too low. If your idle speed in neutral is below 1500 RPM, the sudden load increase when shifting gears can cause the engine to stall. Worn spark plugs can also cause this, as they may not ignite the fuel cleanly and efficiently. For older cars with carburetors, you should also check if the air-fuel mixture is incorrect or if the throttle is sticking. Electrical issues shouldn't be ruled out either, such as poor contact in the ignition coil or distributor. I recommend first adjusting the clutch free play, then checking the idle speed. If that doesn't help, replace the spark plugs. If the problem persists, it's best to consult a professional mechanic.
