Spark seems good now...I did notice oil around the bottom of the balance shaft seal...Dumb question : if the crank seal wasn't sealing why would it lock the engine... also if the crank seal was sealing would it allow oil from the leaky balance shaft seal to be drawn into the jug...Not sure what jet size i'm running I do know the clip on the needle is in the third position....I have found no mods on this quad so I 'm thinking they are stock