Harley Davidson 1927 model J 989 cc IOE engine 27 J 12094
It took the Harley-Davidson Co. about 12 years to develop their motorcycles from a single cylinder belt driven single 3 HP machine to the 45 degree V-twin with 3-speed countershaft gearbox that was marketed in 1915.
This sturdy 989 cc ( 84x89mm) machine became a popular choice for motorcycle buyers all over the world, private enthusiasts as well as police forces, postal sevices and other government bodies.
The OHV inlet, side valve exhaust concept was used till 1930, when HD chose the full sidevalve engine concept. For 1927, no more than 3561 model J machines were sold; the 1200 cc JD was much more in demand with 9691 units leaving the factory.
Not surprisingly perhaps, as the price difference between these models was a mere $10.
1927 was the fist year of the “wasted spark” distributorless ignition system using a circuit breaker and a single coil firing both spark plugs at once.