Circa mid 1940's
Design history:-Designed and manufactured in Czech Republic by Gustav Busek in 1947.
Iron piston with steel cylinder sleeve;
Advanced design transfer ports (similar to those of the more powerful Webra engines); and
Manufacturing nice touches (note the ball end on the tip of needle valve)
Specifications:-Bore 11 mm
Stroke 13 mm
Displacement 1.25 cc
Power approximately 0.1 hp
Maximum speed 11,000 rpm
The cylinder is very similar to the J B engine. It has a special transfer system of the ports. Similar to the very powerful Webra engines. This shape of transfer ports results in maximum cylinder filling on the intake stroke; only engines with modern type snuerle porting are more efficient. Take a close look at the needle in the pictures and you will appreciate the extra care that the Czech craftsmen took when they produced these magnificent little gems.
I wrote about some of this in my video clip: about Its slightly cone shaped with a small ball end~~so much extra work,but so lovely!
This posting is prepared in collaboration with YouTube Channel valic000
Visual material and observations by valic000