2006 Harley Road King Engine Troubleshooting

These troubleshooting steps can help you get to the bottom of some common engine problems.

Many Harley Davidson Road King owners like to get familiar with their bikes and how they operate. When there is a problem with the engine, they are anxious to troubleshoot and learn fix it themselves. This checklist can help solve some possible operating problems, and resolving them will help keep your bike in good running condition. More than one item could be causing your problem, so check all areas. If things get too complicated, be sure talk to your mechanic.


Engine Does Not Turn Over

1. Turn the ignition switch to “on.”

2. Inspect the battery cable connectors and terminals to be certain they are attached correctly. Clean the cables and terminals with a wire brush if they look corroded or dirty.

3. Check to make sure the motorcycle is not in gear and the clutch is not pulled in. Squeeze the clutch lever against the handlebar.

4. Look at the engine stop switch and make sure it is in the “on” position.

Engine Turns Over But Will Not Start

5. Check the gas tank to make sure it has fuel.

6. Check the fuses. If one of the fuses has blown, this will prevent the engine from turning over.

7. Check the battery terminals to be certain they are not broken or loose. The battery top must be clean and dry. Inspect the screws, clamps and cables for corrosion. Clean if necessary.

8. Check the spark plug cables to be certain they are not loose or cracked and shorting out the engine. If the cables are worn or cracked, they need to be replaced.

Engine Starts Hard

9. Check the weight of your engine oil against your owner’s manual. Be sure to base it on the current season. If it is winter, the oil may be too heavy.

10. Check the spark plug cables to be certain they are not loose or in bad condition. If the cables are worn or cracked, they need to be replaced.

11. Look at the cable connections at the battery terminals to see if there is a loose wire or a loose connection.

12. Remove the spark plugs with a 5/8-inch spark plug socket and examine them. A sooty, black deposit indicates that the engine has been idling too long. If the deposit on the plug is wet and black, the plug is fouled by oil. Both of these will cause the engine to function improperly.

Engine Overheats

13. Check the oil to see if there is an adequate supply. Start the engine and let it idle until the oil and the engine are warm before checking.

14. Test to see if the oil returns to the pan if there is enough oil. The oil may not be circulating properly. After checking the levels, wait three minutes for the oil to drain down to the pan. If the oil does not return to the pan, shut off the engine until you find the problem.

15. Turn off your motorcycle if you have been idling for extended periods of time. This will cause the engine to overheat.