grinding

[400sEXridr]

in the top of each gear, my 400ex is making a grinding noise. my dad suggested it was the drive chain, but i tightened that up and it still makes the noise. What could this be?

[PBlackmon]

I don't know what it could be. :confused: You might want to take it to a shop and let them try to see if they can fix it before you REALLY tear something up.

Just my suggestion;)

[HRDROKR18]

its probably the bearing in the rear end of the swingarm

[prepracing]

is your chain lubed up good, it could still be grinding on the chain slide or have trash packed up around your case saver. If none of that then probably axle carrier bearings