|Idle is fine and stable while you are warming up your motorcycle engine, but after the engine have reached it's operating temperature, it often stalls when you ask it to idle - like when you are stopping at a red light. And the problem is often worse on a hot day. |
The dreaded stalling issue when the engine is warm is the most common idle problem and it is mostly related to the very lean air/fuel ratio on the modern fuel injected motorcycle engine.
Why does my motorcycle stall at idle when the engine is warmed up and at operating temperature ?
As mentioned above, the most common cause of the stalling problem is that the motorcycle engines are forced to run way too lean - but of course there is an array of other possibilities that can cause a warm engine to stall:
- Air/Fuel ratio too lean (By far the most likely cause)
- Engine idle level set too low (You will not be allowed to adjust it on all models - especially not on newer motorcycles)
- Clogged charcoal cannister in the fuel tank ventilation line
- Faulty Lambda Sensor (Does not always flash a warning in the dashboard)
- Fuel pressure too low
- Leaking intake rubber hoses between throttle valve housing and cylinder head
- Throttle valves not correctly synced
- Throttle position sensor (TPS) not correctly adjusted
- Valve clearances are too tight
- Low compression.