Hi Brian, What Grumpy has said is all very true. Dirt is the arc enemy of Chain saw chains and bars.
I feel that you have been conned though by the chainsaw shop that sold you the new chain without offering to sell you a new sprocket.
From the worn condition of the chain you took in to get a link taken out of, they would certainly have known that the sprocket would be worn to an extent that it would need replacing
For them to refuse to shorten the chain on safety grounds I find very strange, as it it quite a normal thing to do.
With the tight spot in your new chain,it may well be that it is riding up on the worn sprocket, but also, have a look and see if you can find where the chain has been joined up.
Most shops keep the chain in bulk on a roll and cut off new chains and join them up.
It may well be that someone has tightened up the chain at the join by being too heavy handed with the pressure on the rivet spinner, and the chain is not free in the join up link.
You can pick out the joining section if you look carefully at how the rivet heads appear all around the chain, then pick out the difference in the appearance of the rivet.
You will need to look at both sides of the chain though as the new rivet rolled over, will only be one one side. Cheers Joe
