Wiring outlet off of existing fuse?

I want to wire an outlet on my bike and don't want the power on when the bike is off. I know I can wire in a relay but came across a utube video (pasted below) which seems to accomplish the same goal without the relay. The guy just wires the power against an existing fuse. Is this ok to do? Any risks I should consider before going this route? Appreciate any advice!

YouTube - Install a GPS on a Motorcycle

FazrDan said:

I want to wire an outlet on my bike and don't want the power on when the bike is off. I know I can wire in a relay but came across a utube video (pasted below) which seems to accomplish the same goal without the relay. The guy just wires the power against an existing fuse. Is this ok to do? Any risks I should consider before going this route? Appreciate any advice!

YouTube - Install a GPS on a Motorcycle

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Depending on the load your going to carry, IE, a charger for a phone, GPS,(light load) etc, you can just tie into the front directional running lights, or something similar. It'll turn off with the ignition and on with it as well.

For an outlet you may use for heated gear, I would use a relay and just use that running light line as the trigger for your relay...

The risks are should you put too much load on that circuit, you'll blow a fuse and something will NOT work depending on what you tie in to...

Its really not difficult to wire in a relay and of course easier to run directly to the battery (with an inline fuse)

My GPS is wired to my ft directional running light. The left side outlet is wired hot all the time thru the fuse block-wired direct to the battery(it must be hot all the time if your going to use a charger and is handier when when running an air compressor)... The Stebal air horn is wired thru a relay (to my fuse block) as the stock harness CANNOT carry the load needed for that, the trigger for the horn is the stock horn wires...

I'd be worried about the current draw going with an existing fuse. Depends on what you want to run from the switched power outlet and the rating on the fuse you select. Might be ok for a GPS but what if you later want to run a phone charger or heated grips etc.
Best bet would be to use the fuse as a powered source to switch your relay running direct from the battery. Do the work once with the relay and you have a switched source for plenty of future uses.
I run a non switched , but 30 amp fused connection but only for the tender.
I ran a relay for the Stebel Horn, a bit of mucking around, but I know where the power is available from now and I can add more if I need to in the future with out risk to any of the OEM wiring loom

If you want switched power the best way is the relay. You can run high current if needed and don't risk compromising the circuit you wire into.