ESO 250 Single


Miloslav Soucek used this desmo-machine in the 1962 Swiss GP
Source: MOTOR vol. 49. issue 16. april 20, ’62. ESO is the Czech word for “ace”.
Source English article “Big-Track Eso desmo”: Motor-Cycle; 15 Nov. 1967: Vol. 119, No. 3361
De Desmodromische E.S.O. / G.K. in: Motor; jrg. 49, 20 april 1962 no 16 p. 365
1960-1962 Prototype of Motorcross motorcycle “ESO” MC250 with desmodromic engine.
January 2012 Massimo Clark revealed the colour pics of the desmo-heads.
The sliding camfollower body very much resembles the Czech Karel Horal system. Not a radial valve type engine, but a “simple” two valve desmo system and not using the conical Horak cams but the Delage type system.
The patentpictures and the B & W picture of the engine are from the book Motocykly z Divisova Historie zuzek ESO a JAWA from Jan Lahner a Miloslaw Straka.
I finally discovered the whole patenttext (2013-11-16), translated this text and interpreted the drawings once more.
The inventor was (Eso / Jawa) chief engineer Jaroslav Cervinka, the spiritual father of the Czech speedtrackraces.







3D picture of the actual ESO-desmo (nb slightly differs from the patentdrawing)

Patent Cervinka, Jaroslav

Classification = Group4

HorakartikelStrada 8 v2