Losing a dribble of coolant after we stop. It’s coming from the thermostat/pressure cap area so I’ll need to take the (sodding) tank off to investigate.
Best scenario: tighten hose, top up system, get a beer.
More likely scenario: coolant escaping past the cap instead of venting through the header tank. If this is the case, I expect the system to be low despite the header having coolant in it. To counter it, I will consider sealing the cap (not the pressure release part) with sealant. Advice on this welcome.

Looking like a proper Triumph. Except it’s water, not oil.