Josef Linhart made the JOLI between 1947 - 1950, the name being derived from the first two letters of his first name and his surname. You will note (left) that it was in fact a replica of the JAP engines of that period.
From 1950, Jaroslav Simandl bought up all the remaining spares of the by now defunct JOLI engines and used them to produce his own version - the ESO (see below).
The JOLI engines were fitted with a Bronze cylinder head and used five holding down bolts, whilst the early ESO's came in three variety's:
1. With Bronze head and five holding bolts.
2. With Bronze head and four holding bolts.
3. With cast iron head and four holding bolts.
A timeline of the ESO Production years was kindly sent in by Andrew Cooper. This has been posted to the ESO History page.
Seen Right is one of the later versions of the early ESO engines. Still built from JOLI parts, this engine used a cast iron head and four holding down bolts.
ESO of course went on to develop
more modern engines, before finally being bought up by the JAWA company.
The ESO company made Speedway and Grasstrack machines using 500cc and 350cc
models and weighed in at 182lbs.
A lovingly restored ESO/JOLI (Above) owned by Roy Young, this particular machine is of the 5-Stud Bronze Head type. The pictures below are of Ian Paterson's excellently restored 1951 ESO, and clearly shows the extra adjusters on the clip-on style of handlebars.