The first models of motorcycles of the JAWA family required improvements, which the Czech manufacturer successfully carried out throughout all the years of production. And if at first Java model number 634 (see wiring diagram) switched to 12-volt equipment experimentally, then model 638 received this configuration as standard.
Factory wiring diagram Java 638 in Czech
Advantages of BSZ over KSZ
While writing the article, I sat and thought and thought, and still did not come to the conclusion of what exactly is the main advantage of BSZ; for me, all the advantages listed below are the main ones and are equal to each other.
— High stability of engine operation (synchronous operation of the cylinders, strictly in turn)
— Frisky review of the throttle
— Better engine thrust (which allows you to easily use the largest drive stars without difficult acceleration!)
— Candles “live” four times longer than on KSZ (I’ll write about this separately below)
— Less well-known “snot” from Java mufflers (since fuel and oil are burned much better)
— Longer service life of all crank bearings (as there is less extraneous detonation and vibration)
— Less fuel consumption (since it burns better, the carburetor must be adjusted to a lower fuel supply)
