You could have a tight link in your chain or need a bottom bracket rebuild. To check the chain, put the bike upside down and turn the pedals slowly and watch for one of the links to lift slightly, if it does just work the links on either side until it loosens up. Hopefully that is what the problem is. Now, if it is the bottom bracket, take it in for service because you have to have special tools to take it apart. Good luck
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You could have a tight link in your chain or need a bottom bracket rebuild. To check the chain, put the bike upside down and turn the pedals slowly and watch for one of the links to lift slightly, if it does just work the links on either side until it loosens up. Hopefully that is what the problem is. Now, if it is the bottom bracket, take it in for service because you have to have special tools to take it apart. Good luck