Took the liberty of riding a mates freshly purchased bike from Penrose to Birkdale, ran sweet as fuck and didn't skip a single beat.
I got a text about 30 minutes later, asking 'Why the fuck wont my bike run?'

He's getting about 5-10 minutes of ride time before it suddenly cuts out and wont turn back on for a couple of hours.

So far we've thought about;
Fuel pump, maybe it's on the fritz and doesn't like running for long
Overheating ECU or the likes
Maybe the thermostat isn't opening once it warms up and there's a thermal cutoff somewhere.

I haven't actually been around to check it out myself, and neither him nor myself are terribly clued on past changing oil filters.

Is there anything else we should check en masse?