Misfire

[ian1987]

I have a 2008 EC300

It runs perfect low down and to about 3/4 throttle however just when you'd expect it to come into the power, it goes flat and starts to splutter.

The bike previously ran perfect to full power so I know jetting isn't the issue. I've cleaned all carb jets and put in a new plug

Bike is run at 50:1 with good quality oil

Im beginning to think the power valve isn't operating properly. Anyone have any ideas?

[Anders]

Originally Posted by ian1987

I have a 2008 EC300

Im beginning to think the power valve isn't operating properly. Anyone have any ideas?

Take off the RH power valve cover and have a look. Perhaps the actuator arm is broken. Start the engine. It will make a lot of noise, but it will run. See if the arm moves up and down as expected.

[Zman]

Yes check the power valve.

[pscook]

Also check to see if your silencer/spark arrestor is plugged. The packing can get soaked with oil and collapse, thereby restricting the exhaust.

[ian1987]

Originally Posted by pscook

Also check to see if your silencer/spark arrestor is plugged. The packing can get soaked with oil and collapse, thereby restricting the exhaust.

There seems to be a fair bit of oil around the end of the silencer, I will repack

The power valves seems to be properly intact

[RBrider]

Have you checked for a blocked air filter? Beads of water in float bowl?

RB