Fuses are normally rated to the size of the cable they're protecting to prevent overload and fires.
Assuming the cable is a sufficient size to carry enough power for what it's feeding I would use a fuse rated at just over the maximum load of what it's feeding/protecting.
LED lights and USB ports use very little so I would assume 5a would be sufficient for them.
When I install Hella 12v sockets for accessories I use a 15a fuse so it won't blow if I plug in a tyre inflator compressor.
Gentlemen, many thanks for the responses, as usual you guys are brill with all the info. Cheers again and happy New year to you all, let's hope it's better than last one. Stay safe, Steve.
Hi shandy, I stuck it on the front of the touratech tower I've fitted, behi d the fairing. Not ideal if its raining, saying that it hasn't been wet yet, and at night if away, cover the whole fairing with a rucksack cover. I mounted the fuse block there as its accessible, without to much trouble, just two bolts and fairing off.
Hope this helps.
Thanks Wardy, I've got an Xcountry so no tower the only place i can come up with is on top of the airbox or on left hand side of airbox under the cover it should be kept dry there but defo not ideal probably should have gone for the eastern beaver one but postage and taxes put me off.
Thanks