On the subject of mowers.. Got a free mower from a neighbor a few days ago.
A John Deere LX188 circa 1997, featuring a LIQUID COOLED 437cc Kawasaki V-twin. I didn’t know liquid cooling was available for mowers like these! Definitely a lot cooler than the air cooled Briggs thumper in the also free snapper riding mower this will be replacing. Also has an actual oil pump and filter, the Briggs has neither. A comparable new John Deere would be nearly $2000.
The liquid cooling helps power and efficiency, allowing a 9.3 compression ratio and supposedly 245 g/hp/hr.
Edit: Maybe not all that efficient? Plugged that number into a calculator saying metric horsepower and it turns into 333 g/kw/hr, not really impressive.