Replace or upgrade your worn chain and sprockets with this market leading sprocket kit featuring quality JT Sprockets and D.I.D chain brought to you by THS Moto. Note the chain may need to be adjusted to length using a chain breaker tool. This Sprocket Kit contains a 13 tooth front JT sprocket and 51 tooth rear JT sprocket with a 520DZ114G 114-Link 520DZ2 solid bush Gold & Black clip link DID Chain Fits: Yamaha WR250F 2020-2021 YZ250F 2010-2013 YZ250FX 2015-2021