There's a lot on the etecowners group about batteries & cables, the general consensus is that relatively large batteries are specced due to the long cable runs compared to auto applications. The volt drop can be excessive if the battery isn't up to it, as the EMM needs 55v to fire up the ignition circuit on starting. It achieves this by stepping up the 12v electronically, if it doesnt get a good battery voltage, it can cause staring problems. Saying that I am using about 6m long 35mm battery cables to my 115s without problems, but I am also using Optima blue tops.
Rule#2: Never argue with an idiot. He'll drag you down to his level & then beat you with experience.
Rule#3: Tha' can't educate pork.
Rule#4: See rule#5