Subject:RE: RE: RE: what year is this motor?? Date:Sun Mar 12 18:14:51 2006
Response to:1173

thanks I do see a "17-17" between the castings along the main shaft. how hard is it to find a bottom pan and the one gear set? shure looks like the later motor I have but much smaller..
thanks again,pat
I believe it is a 1917 motor. The intake rocker towers are of the early type and the motor is fitted with the oil drain feature that wasn't used on a 1919 motor. I put no trust in any of the serial number lists I have seen. Motor #'s for Detroit Henderson's are all over the map and I have never heard, or seen of any legitimate documentation that came out of the Detroit factory. Most serial number documentation can be attributed to Ballack, which I believe is very loosely based on Excelsior data. Excelsior data is very mysterious. My theory is that Schwinn would not commit serial #'s to a specific year because he had so many cross-over years in motor castings and frame forgings. I do believe the Excelsior factory could tell what year a specific motor was made by the serial number but I have never heard of the existance of that data either. If you read the letter reprinted in Rich Schultz's book "Hendersons, those elegant machines" on page 12 you will be inclinded to agree with me. Excelsior history was based on the memory of long term employees like Gideon Haynes and he admitted that he couldn't locate old records, let alone a master serial number list that would identify years. I'm getting way off base here. Take a look in the main bearing area between the 3rd and 4th cylinders. There should be a cast in date code. At least there is on my 1917 Hen.

This motor bears an uncanny resemblance to the 1920 Ace motor , doesn't it? It is as if Mr. Henderson was working on improvements to the motor while he was still at Excelsior, and took the next iteration over to Ace Motor Company, in the form of the 1920 Ace.

Based on your serial number, and ccording to this may be late 1917 or early 1918.


wondering the exact year of this motor I just dug up. it has a number of 9185 on the side there is no abcdefg of any kind.