I have an old beach cruiser I’ve been riding for a month with the “80”cc bike engine kit attached. Let me be clear, my alignment and chain size are fine. The engine also runs smooth as butter. The problem started two days ago and it started as a light squeak which goes away after running the engine but then started to become more aggressive, keep in mind that this happens while coasting and until now didn’t happen with the engine on. Now the chain is seizing and I could barely get home because I didn’t want to stress the engine. I’ve narrowed the problem to the front sprocket and it is now squealing like a pig and is locking up, any idea what this is or how to fix it?