Need help identifying the motor on a shovelhead i was given. The vin stamp on the crank doesn't match whats on the bike and its a bit of a Frankenstein.
Engine vin numbers should be low and on the front of the cases, should match the neck. It's 70-84 as a cone side, and 74 ci stock. If it's been redone, there's no way to know displacement without taking it apart and measuring the wheels and bore. Not a lot of changes 70-84, so a service manual should be pretty easy.
Hopefully this chart helps. I believe in 79 is when they started the 80ci shovel motor. I don’t remember if it was just done with a bigger bore or longer stroke. If the 80ci has a longer stroke you can measure that but taking a spark plug out and sticking a piece of tig rod, coat hanger, whatever, in the spark plug hole down to the piston, roll the motor over with the back wheel, or kicker if it has one and measure the distance of travel from bottom to top.
Edit: I see in the pic it’s e start only. So back wheel in high gear will work to roll it over.