HERCULES, by Bob Shores

The Herky is a smaller version of the Silver Bullet for the benefit of small lathe owners such as Sherline lathes. Some design changes were made to offset the effects of reduction, such as, shorter exhaust tunnels and longer inlet tunnels to reduce engine temperature by about 40 degrees. The carburetor was relocated to reduce congestion and roller clutch starting is standard. At engine shows, I charge the kids 10 cents to crank the Herky, they will never forget the experience. The Herky is my favorite, beautiful, reliable, pleasing sound, easy starting and not a difficult engine to build. Ben Imbrock purchased serial number 1, in July of 2001.



Two cylinder, four cycle gas engine, Water cooled, OHV side operated, automotive type engine, Constructed using a casting kit.

Construction casting kit

Height 4.6

Width 3.0

Length 6.00

Bore .625

Stroke .625

Cylinder liner cast iron

Pistons Aluminum

Flywheel 1.88 OD

Exhaust opens 120 degrees ATDC

Exhaust close 5 degrees ATDC

Ignition Adjustable Two spark coil

Sparkplug 1/4-32

Sparkplug gap .015

Antifreeze 35 cc

Oil lOwt 25cc

Water pump Gear type

Fuel 9 parts unleaded gasoline/1 part WD-40


The following are some in progress pictures of a Hercules being built by Bruce Harr ( havnfun@preferred.com )

Cam and Crank shafts in block (1/3/2002)

Better view of crank shaft (1/3/2002)

Timing gears (1/5/2002)

Points (1/5/2002)

Block and oil pan before points were added (1/5/2002)

Block with rear bell added (1/5/2002)

Timing Adjustment lever (1/11/2002)

Front timing gear cover (1/11/2002)

Top (6/17/2002)

Side and mounting Base (6/17/2002)

Pistons (8/27/2002)

Almost 100% (8/27/2002)