[alantf]

Let's try to liken this to your house wiring. The cable on any circuit will only take a certain current before it overheats and melts, so you put a circuit breaker (same thing as a fuse, but resettable) in the line, that blows before you get a dangerously high current. Same thing with a bike. Suzuki recommend 0.75A to recharge the battery. A car battery is designed so that to start the engine, it uses a high current from the battery. Once the engine is running, the alternater shoves a high current into the battery to get it fully charged again. If you jump your bike with the engine running, the high current will shoot across, heating everything up, frying the battery, and possibly melting the cables of your bike, that aren't designed to stand them.
Hope this helps explain this. Until I retired, I was an electrician for 50 years, so I can assure you that jumping a bike from a car with a high charging current WILL fry your battery.
Remember, power = volts x amps, so in America, at 115v, for any given power, the cables have to be twice as thick as European circuits at 240v. Transfer this thought to your bike.