I have a 99 YZ400F that doesn't get ridden much. I went out to the garage to start it the other day and went to kick it through to find the TDC and it had no compression. I went to pull the compression release and it wouldn't pull. I guess it is time to pull it down. Has anyone have any ideas as to what it might be? It is garaged & doesn't get started but every 3 or 4 months.