When jet ski's don't run right...

Took a look at a friends Yamaha FX FZR Waverunner today. He complained about the jet ski running weird and shaking at low rpms. He said he felt a decrease in speed and acceleration. I took it for a quick spin and realized that it felt like it was running on all of 3 cylinders! Well we took it back to the house and decided to investigate. It looks like the spark plugs finally gave out! This is very typical on the Yamaha line. If you ever have any rough riding Yamaha check the spark plugs first. They can get easily fouled out and need replacement. Below is a picture of the spark plug in cylinder #3. This is a 2009 Yamaha FX FZR with 120hours of ride time (2nd Spark Plug change to date). After we put in the new spark plugs we fired it up and it ran like new again! Also managed to change the oil at the same time :)