peter reeves wrote:
I have not heard of any genuine 30s or 40s Harleys with numbers below 1001, except the one Chris mentioned, so could this be a trick question.
Is it possible that completed bikes where assigned the serial numbers after they came off the production line and after they had been tested?
Always willing to learn more, don’t keep us waiting to long with your answer.
It's not a trick question. And I won't prolong the agony much longer. But I'm very interested in learning what most people think is correct first. No offense to anyone, but mostly it's wrong.
As to when bikes were stamped with their serial number it was NOT during final motorcycle assembly.
It went this way:
Each engine was stamped when it was done being assembled in motor assembly and the number was entered in a special book. Then the finished motors were normally sent to the motor storeroom where they remained until enough orders came in to assemble a batch of any certain model. There are published Factory photos of the motor storeroom FULL of knuckleheads.
A beautiful sight indeed like Aladdin's Treasure Cave!
When taken out of the motor storeroom no attention was paid to motor serial number. They were just told: "Get me 10 EL motors." However, at times when orders were coming in fast and furious motors were sometimes assembled when the parts were still hot from being machined and these motors might have gone directly to the final motorcycle assembly thus bypassing the motor assembly room.
Thus, there was no consistent system of how motors or motor serial numbers went into finished bikes. That is, you might get a bike with a low serial number that had been in the motor storage room for some time and was assembled into a motorcycle later in the model year. Again: no consistent system except that serial numbers got higher as the production year progressed.
This info came directly from Harley factory workers including guys who worked in motor and final motorcycle assembly and from one guy who stamped in the numbers. Some of these guys were nearly 100 years old and couldn't remember why they had gone into the bathroom, but their job at Harley was still crystal clear in their minds (well, some of them at least).
PS: I never asked any old timer if crankcase "belly" numbers related to motor serial numbers but I doubt it. Like Johnny already said there is apparently NO relationship between belly numbers and motor serial number because there didn't need to be.