Self contained V-Twin engine as it is operated at shows with
fuel tank at left and starter/generator at right operating light
battery, ignition system and fuel pump are in the oak base.
This is a V-Twin engine that is machined entirely from bar
stock. It has no prototype as it is entirely my own design. Being
a single crank pin 90 degree engine, it is extremely smooth and
vibration free. V type engines other than 90 degree can
not be balanced except with special balancer shafts, etc. that
you wouldn't want! Witness the vibrating 45 degree motorcycle
engines...... The engine is a long stroke, moderate speed design
which provides plenty of torque. A robust cooling system allows
the engine to run indefinitly with a load and never overheat.
Cylinders are of cast iron. Crankshaft is steel. Most of the rest
of the engine is of aluminum alloy. Knife and fork aluminum alloy
connecting rod ends operate on a single hardened crank pin. This
configuration produces an interesting exhaust sound! An internal
oil pump ensures that lots of oil gets to all the internal moving
parts. The crankcase holds two ounces of oil.
The engine is equipped with ball bearings on all rotating shafts.
A sheet metal shroud on each cylinder/head directs cooling air
from a pair of belt driven fans. Dual 2-Jet Throttles have oiled
foam air cleaners. The valve rocker arms have ball bearing rollers
on the valve stem end and clevises with lock nuts on the push
rods for valve clearance adjustment on the other end of the rocker
arms. The valve train is designed so that there is no side thrust
on the tappets or the rocker arms which causes undue wear on other
The engine operates without any oil getting on the outside due
to "O" ring seals at all joints and an efficient crankcase
check valve ventilation system which maintains negative crankcase
The ignition system is twin Hall sensor and twin TIM-6 electronic
ignition modules and two model engine coils operating on 6 volts.
Each cylinder is treated as a seperate engine and this precludes
the need for a distributor. The spark advance/retard is easily
adjusted during operation. Spark plugs are the low cost 10mm NGK
This is NOT a beginners project, but anyone who is particular
about his work, has built a few other successful internal combustion
engines and has a 7 inch or larger lathe and a milling machine
with a 6 inch rotary table should not have any problems building
Besides just being a nice engine to have and operate, this engine
would be great fun on a bicycle or in a radio controlled boat,
car, tank, etc.! This is a small "real world" industrial
quality engine capable of doing "long hours" of hard
work. My engine operates all day long at shows driving a generator
and is stopped only long enough for refueling.
The plans include all engine features
in the photos (except the mounting rails) including the throttles,
cooling fans and air shrouds, plus an ignition system schematic
diagram and timing gear cutting charts.
The quality CAD generated and laser printed plans set consists
of 41 sheets of drawings and 3 sheets of construction notes.