Sold Partner S65 chain tightens by itself

[dyager]

Got a wierd problem. Partner S65 chain tightens up as normal but gets too loose in short period of time. When I tighten the bar nuts I can see the chain tightening too. If tightened properly and I run the chain around the bar, it gets tight in one spot and then loose again. Could I have a bent crank? That’s the only thing I haven’t eliminated. Your advise is most welcome!

 

[Brufab]

Make sure you hold the bar all the way up when tightening it.

 

[dyager]

Make sure you hold the bar all the way up when tightening it.

Yup got that covered. Even put an older bar and chain on it and it does the same thing. It just started doing this

 

[stihltech]

Sprocket wear, bent chain, buggered driver. Moving ahead when tightening is usually a bent tightener peg or screw. Also a bar roller nose may get tight when the chain is on only.