I have a problem with starting my DT28, initially I thought it was a number of issues including the battery. On attempting to start with a fully charged battery it will turn over fine and the plugs spark no problem but won't start. When trying again, it appears that the battery is completey drained and it will only turn over very slowly until I re-charge the battery again ? - I've changed the solenoid, starter, plugs and bought a new battery just in case to find it still does this ? - I've also drained the fuel system and carb and cleaned out the jets. If the plugs are removed they blue spark against the chassis and it turns over as expected - I'm at a loss now ? - Can anyone help please ?