Dodgeman wrote on 06/02/13 at 11:51:34:On a 2006 S-40 Boulevard, how does one take the tank off, to get at the spark plug?....
You're presuming that the tank has to come all of the way off in order to access the spark plug.
Not true (at least on mine - see my signature block)!
Here's what I do:
1. Remove the seat.
2. Remove the two bolts from the rear of the fuel tank.
3. Remove all lines (fuel and vacuum (if you still have one)) from the petcock.
4. Move the fuel tank back a bit, then prop up the rear of the tank with a short section of 4" X 4". This will keep the tank out of your way.
5. Remove the port chrome beauty cover.
6. Slap a wobble adapter onto your 3/8" drive ratchet. Pop an 18mm deep-well socket on the adapter and you've now got access to the spark plug.
Note that, when using this method, I do not have to disconnect the speedo cable or the electrical connector.
IHTH!