rr4406pak
11-01-2004, 01:48 PM
Hello Exriders,
I have a stock 01' 400EX that I have a big problem with.
At high RPMs I lose power and get this massive vibration in the motor (almost like a violent harmonic resonance). Why? :confused:
It is not because of lose exterior bolts (like skid plate, motor mounts, etc. I triple checked). At low to mid RPM I have plenty of power and all is fine.
When I first bought it it did not have this high RPM vibration. Everything was fine.
It is not overfilled with oil.
I have not checked the valvetrain or attempted to adjust the valves.
One strange thing that happened is that when gas knob was set on "ON" it would not start. When I turn it to "RESERVE" position it starts up and runs fine (BUT I STILL HAVE THE HIGH RPM VIBRATION). It is clear that some junk has gotten into my gas tank/fuel lines and is blocking up the works.
Is it possible that the engine is starving for fuel at high RPMs due to a blockage??? :huh Would that cause the strange vibration/loss of power???
The vibration feels bad like something is going to break inside.
I do not race. I can still ride this thing very fast but I can't push it like I should be able to.:grr: What fun is that?:(
HELP!:mad:
I have a stock 01' 400EX that I have a big problem with.
At high RPMs I lose power and get this massive vibration in the motor (almost like a violent harmonic resonance). Why? :confused:
It is not because of lose exterior bolts (like skid plate, motor mounts, etc. I triple checked). At low to mid RPM I have plenty of power and all is fine.
When I first bought it it did not have this high RPM vibration. Everything was fine.
It is not overfilled with oil.
I have not checked the valvetrain or attempted to adjust the valves.
One strange thing that happened is that when gas knob was set on "ON" it would not start. When I turn it to "RESERVE" position it starts up and runs fine (BUT I STILL HAVE THE HIGH RPM VIBRATION). It is clear that some junk has gotten into my gas tank/fuel lines and is blocking up the works.
Is it possible that the engine is starving for fuel at high RPMs due to a blockage??? :huh Would that cause the strange vibration/loss of power???
The vibration feels bad like something is going to break inside.
I do not race. I can still ride this thing very fast but I can't push it like I should be able to.:grr: What fun is that?:(
HELP!:mad: