3 - 4mm really isn't going to sap any power, or cause any significant extra wear. Personally, I'd just ride it. Have a read of this ...
http://blog.pedalitis.com/2013/03/05/the-amazing-unimportance-of-chainline-and-chain-lubrication/
@Picard started
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3 - 4mm really isn't going to sap any power, or cause any significant extra wear. Personally, I'd just ride it. Have a read of this ...
http://blog.pedalitis.com/2013/03/05/the-amazing-unimportance-of-chainline-and-chain-lubrication/