Burr on bar of ms390?

Just file the burrs off. Grease your spocket if it has a hole. Sometimes real worn bars will have the slots open up wider. They make a tool to reclose it to proper gap. If your still cutting straight though I would just file down the burrs and go on.

Every few weeks depending on use I flip the bar,check for burrs,file them off if needed.Sprocket nose gets greased every fuel up.

I'll bet you've been pushing it- continuing to cut by jamming the bar into the cut, making dust/heat/bar-wear when you'd do better by sharpening the chain. As long as the rails are about even height, not spread, and not worn to where the drive links bottom in the grooves, you should be okay, just file off the raised areas on the sides as others have advised.

I'd suggest filing the chain more often, and flipping the bar after each day of cutting. Good chance to scrape out the grooves and clean oil holes.

Chain slap.
Tighten your chain more often.

I'd just file it off--same thing happened to my bar a few months ago. Filed the bar and flipped it--no real problems since.

fortunateLEE said:

Chain slap.
Tighten your chain more often.

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You might have something there. I've only filled one bar in my life. My neighbor has to dress his all the time. Now I realize he cuts way more than I do but I'm anal about chain tension and some people will run them till the almost come off or do. Bugs the heck out of me when I see someone running a saw with the chain hanging down.

wkpoor said:

Just file the burrs off. Grease your spocket if it has a hole. Sometimes real worn bars will have the slots open up wider. They make a tool to reclose it to proper gap. If your still cutting straight though I would just file down the burrs and go on.

Click to expand...

OEM Stihl bars will not have a grease fitting/hole.

I just run one of these over the bar a few times once in a while to square up all the corners.

http://www.amazon.com/PFERD-13025-Universal-Edge-Sharpener/dp/B000HD4LWI

I think of bars & drive sprockets as a wear items like brake pads on your car. They will wear out and need to be replaced eventually. So I wouldn't be concerned about it, but I would try to keep them square, smooth, and well oiled. That way they will last a lot longer before wearing out.