Suzuki GT750 “kettle”

The ever popular Suzuki GT750 known as the kettle is a regular selection for restoration and preservation, see this link to one of my favourite magazines and websites https://www.real-classic.co.uk/2017/09/09/suzuki-gt750/

This bike is already in very good condition. The owner was just having parts cleaned up during a rebuild. The kettle is a 750cc two stroke, 3 cylinder liquid cooled machine. The cylinder head is an Aluminium casting covering all three cylinders, water galleries and a thermostat housing

Cylinder head with slight corrosion visible  Cylinder head showing slight deterioration

It is around 42 years old and shows little deterioration having been well maintained. The casting is in very good condition as a result of correct corrosion inhibitors in the cooling system. There is no sign of damage in the combustion chambers so the part is ready for inspection and rebuilding

Vapour blasted cylinder head casting Vapour blasted cylinder head showing clean combustion chambers Vapour blasted cylinder head showing clean fluid galleries Vapour blasted cylinder head casting showing finished item

The combustion chambers are perfect and fluid galleries free from corrosion. So with modern fluid technlogy the engine should stay in this condtion indefinitely. We noticed that the two outer combustion chambers have angled spark plugs. There are pockets around the plug to enhance fuel burning. The middle cylinder plug position is central so does not need the pocket – nice attention to detail

Are you considering restoring a liquid cooled motorcycle or car with an aluminium engine. If so, always have a good look at the castings and radiator. Look for leaks, ask questions about what fluids have been used and look for a service history

The history should note fluid changes at regular intervals, hopefully showing what was used. Older cooling liquids will change from being protection to an agressive chemical if it isn’t changed

Old fluids should be thouroughly flushed out and disposed of safely, NEVER remove a radiator cap or hose when the engine is hot, the hot fluid will flash off and cause burns and scolds

Modern fluids have excellent cooling properties and good corrosion inhibitors