Have a good look for abraded wiring first as GULG says. 99% of all blowing fuse problems can be attributed to short circuits/short to ground.

Failing that, start with the simple things:

1) Does it blow as soon as you turn the ignition on when the engine stop switch is in the OFF position? If, by chance it doesn't blow in the off position, then the engine stop switch and wiring needs a further look.

2) Pull out the fan relay - you don't need it to start. If the fuse doesn't blow, then investigate the fan circuit.

3) Disconnect the fuel pump from under the tank. Turn the ignition on. If the fuse holds then suspect the fuel pump.

Relays can be tested with a multimeter if you unplug them both for continuity and resistance. Its all in the official workshop manual. However, the easiest way to check them is to borrow someone's running bike and swap them over one by one.

When this problem has come up before it's more often than not been a wiring short, but I have known one starter/main relay be at fault and a few fuel pumps.

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