Sprocket/Chain Bind?

[toolmaker]

Modded MS460 25" Cannon Bar
I switched the 7 pin sprocket to an 8 pin sprocket
When I have the saw in a vise to file the chain, the chain gets "stuck" every few teeth/drivers, only when pulling the chain backwards.

If I have the file in a cutter and give it a little extra push to get through the tight spot, it goes right through and gets stuck again in a few more cutters away.

Could this be that the 8-pin is pushing the limits of teeth/drivers/sprocket diameter and the drivers are binding in a certain position?

 

[Pincher]

I assume you switched the "rim" from 7 to 8. If the rim was brand new it may have some imperfections that will go away with use. I would not consider 8 pin to be pushing the limits of your combination. Personally, I use mostly 7.

 

[AVB]

Make sure the pitch of the sprocket, chain, and bar all match including the gauge of the DLs to bar match.

 

[Deets066]

Does it spin freely when going forward? If not, make sure your drive links don’t have any burrs.

 

[davidwyby]

Run it in

 

[Dub11]

Had a coworker with this problem on a Ms390. The clutch threads had cracked allowing it to over tightened and they new found extra play in the drum was causing it.

 

[Int1968]

Do you need to dress the tail of the bar?