88 Ignition: Magneto
Stroke: 81.7 Inlet Port: 35mm Push Rod operated 4-Valver
Designer: Ed Schafer, Los Angeles, USA
This JAWA conversion was developed by the DRAKE Corporation whose main claim to fame was the fabulous Offenhauser engine as used in the Indianapolis 500 car race, from which the head design was used on the Speedway engine.
The engine was actually designed by Hans Herman who was the chief designer of DRAKE engineering
whilst the owner of the company and chief engineer was Ed Schafer, who also worked for SRS (Speedway
Research and Specialties), and revealed that the 4-valve head was inclined at twenty degrees and pushrod
The engine, tested by American and Exeter star Scott Autrey, became available for the start of the 1976 season and featured a flat piston with 4v cut- out. Mr Schafer noted, "The benefit of our 4v Head is that it bolts on to a JAWA engine with no modifications or machining required. The conversion kit consisted of the following:
Cylinder head complete with valve guides, springs , rocker arms and pushrods.
2 ring forged piston 14 / 1 compression ratio
When you placed your order you sent your cams to be reground and the price of the conversion kit was $ 600.00 US
We would like to thank Bert Sergent from New Zealand who has kindly sent us pictures of the DRAKE (Speedway Research) Motor (currently missing, but may turn up soon. He has recently sent some Speedway Research catalogue images which help with the story.)
About the Speedway Workshop Archive
Triumph, BMW, & Kawasaki Sales Spares & Repairs.
Established for over 40 years and run by expert motorcyclists.
Fully authorised workshop.