Please ID this motorcycle if you can

[Rubone]

I have a lot of books, so am not looking for someone to take their time to do research for me, but a few comments could help a lot at this point. Most of the books I've looked through thus far are vague on model designations, and I've yet to find enough to figure out if HD actually had some sort of logical naming convention. But, to the point, I haven't yet figured out what constitutes a "U" in general, let alone a "UL." Harry Sucher comes closest, but even there it's uncertain. In an Appendix he shows that 74 c.i. U and UL machines from 1937 onwards were o.h.v., whereas 80 c.i. UH and UHL machines 1936-47 were side valves. You guys have said that the '37-'39 ULs were side valve machines, which is inconsistent with information in Sucher. Anyway, assuming "U" is some major category and "H, HL, and L" are sub-categories (which I hope you will tell me is a good assumption, if it is...), what constitutes a "U," and what then differentiates UH, UHL and UL (and other Us, if there are any) from each other?

Having this basic understanding of H-D "U-terminology" would help me a lot when looking through all those books for relevant information. Thanks in advance.

If Sucher said that in his book he is wrong. All "U" series bikes are Sidevalve (flathead) engines.
A basic "U" is a medium compression 74ci engined bike most often used for commercial and sidecar applications.
A "UL" is a 74ci high compression engined bike most often in solo trim.
A "UH" is an 80ci medium compression engined bike used similarly to the U 74.
A"ULH" is an 80ci high compression engined solo bike.
There are a few variations such as
UMG, a special magneto equipped version which is quite rare, built only for a NYPD contract.
UA a military version
A U low compression, basically a U with compression reduction plates under the cylinders.

[Rubone]

Technically, the WL (45") bike also had the carb on the left side too, however, it would be hard to imagine a police force using a smaller 45". Not sure if there is anything in the photo that could identify it as a 45"

All pre'40 45s still used I-beam type forks which differ in appearance head on from '40 and later.

[BoschZEV]

If Sucher said that in his book he is wrong..."

Thank you very much for the U, UL, etc. information in your post. It will be very helpful indeed.

As for the information in Sucher, I realized that I had used the 1st edition of his book when I posed my question, so I just now went back and pulled the 4th "further revised and enlarged" edition from the shelf to see if he corrected himself. Although Appendix 2 has been somewhat reformatted, for the date range 1941-1980 he says U and UL were 74 cu.in. ohv twins (he also lists FL, FLH, and other models as 74 cu.in. models within that date range). However, he does show that 1937-41 UH and UHL were 80 cu.in. side valves.

Again, thanks for clearing this up so I can go back to researching information on the UL...

[Jim]

It was just a 'thought' as I was just thinking that "IF" the town your Dad was a cop in was a 'small' town it may be easy to see some old PD photos. OR the local Historical society for the town.

Too bad we don't have the technology to enhance pictures like the CSI can do on TV. Yep... ONLY on TV they can enhance pictures THAT GOOD!

In our local PD, I remember there being pics of cops standing next to old cars hanging in our local PD. OH... I was there on GOOD terms ;^)

Have fun doing the research!

Rubone did a really good job explaining the model differences too.