QuestionMy bike usually takes over 100 kicks to get started. I can compression start it on a big hill. It takes 5 to 15 tries compression starting on a flat surface by running with the bike. Once the bike is running it runs perfect, sounds great, great power, great response. Once it gets running and I shut it off, it will start on the first kick. I am getting a good spark. I have good compression. Does it sound like a caruretor problem?
AnswerHi Nick,
Sorry for the delay. I'm on vacation.
Q: "...My bike usually takes over 100 kicks to get started. I can compression start it on a big hill. It takes 5 to 15 tries compression starting on a flat surface by running with the bike. Once the bike is running it runs perfect, sounds great, great power, great response. Once it gets running and I shut it off, it will start on the first kick. I am getting a good spark. I have good compression. Does it sound like a caruretor problem?"
A: What is your definition of good compression? Cylinder compression must be within service limits for the carburetror to function properly and engine to run well.
When compression is low, the engine may start and run, but may run poorly or lack power.
Cylinder compression and valve clearances must be within the manufacturer’s service limits for the carburetor to function properly and for the engine to run well. When either cylinder compression or valve clearances are out of service limits, the engine may start and run, but may run poorly or lack power.
Some engines are cold natured. This means the cool temperatures of an engine’s interior surfaces affects how the air-fuel mixture vapors travel from the carburetor, to the combustion chamber.
Normally, the air-fuel mixture remains atomized while en route to the combustion chamber. When the engine’s interior surfaces are cool, air-fuel mixture vapors may easily form fuel droplets. Fuel droplets are much harder to burn compared with air-fuel vapors. The flash point is much different between the two resulting with difficulty starting the engine.
Keeping the engine maintained as per the manufacturer’s periodic maintenance table may help prevent this phenomenon. Some engines are just cold natured by design.
If the motorcycle was stored or not used for two or more weeks, check the carburetor for evidence of varnished fuel. Clean or repair accordingly and try starting the engine.
Verify the spark plug is correct for the MC. Check plug gap and keep the plug cleaned of carbon and fuel.
A blue arc across the plug's electrode indicates a healthy ignition system.
Respectfully,
Mark Shively
