I've shared this before. Remember working in a GM dealership in the 70s. Came across 2 examples of casting flash that caused major engine overheating issues with brand new cars only a few days old. Once the water jacket hole from the right cylinder head to the thermostat port in the intake manifold had casting flash over the hole on a Chevy small block V8. Another time the water pump had casting flash across the inside of one of the return ports in a Chevy small block water pump. Try fixing an overheating issue with those problems??? In both instances there was no water flow to 1/2 the engine.
I wonder where Triumph gets their rims made?