A few months back I went riding and accidentaly put a lower grade of gas in it then what im supposed to. It started to sound kinda funny, so me and my friend took apart the bike and drained all of the gas out of it and changed the oil too. We managed to get it started after and i didnt get to ride again for the rest of the season. This weekend I was planning on going riding so I went to my bike and tried to get it started. It wouldnt start. Someone told me I should try a new spark plug so I went and got a new one and installed it. We tried to kick start it and again nothing happened. We figured that maybe it would work if we "bum started" it. When I put it in gear to try that, it was really hard to push the bike even when I was holding in the clutch. That made it really hard to try to bum start because it was to hard to push. I dont know waht else to do I bought the bike brand new last summer and its ran great till now. I cant get it to start and I cannot think of any reason why. If anyone has any idea how to fix this please help me! Thanks!!!!