Need some help figuring out what year frame I have.
It came with a 56 duo-glide I purchased last year. The 56 engine is in a later swing arm frame.
I don't see any numbers on this frame or Don't know where to look.
Thanks.

 

Duo Glides are 1958 thru 1964, just FYI.

 

Are there casting #`s on the axle plates ?
Front motor mount ?

 

Hi Nimbus,
Perhaps this topic from the "Jockey Journal" forum from the year 2014 will be of some help to you:
Link: https://www.jockeyjournal.com/thread...traightlegged-
frame.140553/
I would prefer not to comment on that topic, as I really lack the necessary expertise.
But to my old eyes, this "straightleg" rigid frame looks quite good, at least in your photos.

Owned a unrestored 1954 FL decades ago, but really messed everything with chopping, polishing, and
chrome plating, turned out in a mess.

Mike

 

Well, if it is a Harley frame there will be some lettering/numbers and casting marks on it. And there will be a date code for the frame on the top right side of the upper motor mount (started late-53). Time to get to paint scraping. Info below is from Palmers books.

Based on first looks I'm gonna say 54-57 straight leg. However, you have a carburetor control coil clamp and that was not added until 1955. That would make your frame 55-57.

Haven't noticed that SpeedingBigTwin (Eric) has posted in a while. He is definitely "the man" on things like this.

 

Thanks Dave. I’m not sure if it’s a Harley frame or not. Is there something unusual going on about halfway down the top engine mount? Or is it just the photo? And has the front of it been trimmed near the opening for the bolt? Or was it made that way?





For comparison here are examples from 1954 August and 1956 March.
Eric

 

Nimbus46, as already indicated, IF it’s a Harley frame we’d expect ID on the forgings and a date code on the top engine mount.
At this stage the toolbox bracket suggests 52 or later. And so would the top engine mount although I’m not sure about that mount yet, as I indicated above.
Centre section of the front engine mount suggests 53 or later.
Front downtubes suggest late-54–57.

What size is the hole in the block I highlighted below? Also please check the hole in the other block which is higher up.





Regarding the 56 engine, is it stamped FL, FLE or FLH? And have you had the serial number, and belly numbers, checked for authenticity? If you’re not sure about them you could post partial photos?
On top of the rear engine mounts are there 7s or Hs? Photos?
Eric

 

Thanks for taking the time to help ID this frame.
Finally got back to it today and wire brushed the paint off the upper motor mount and don't see any markings.
The holes you're referring to are the coil mounting holes right? They are 3/8 x24 thread. I cant see the belly numbers with the belly guard in place and the mount for the voltage regulator covers the rear motor mount.

 

Thanks for the latest photos. As I indicated earlier there appears to be something going on about halfway down the top engine mount. That area looks more pronounced than the same area demonstrated in the two examples I posted above.
I had also wondered if the front of it had been trimmed near the opening for the bolt but judging by your latest photo it appears to have been made that way?






Both those differences make me wonder if the frame may be aftermarket? And that possibility increases because of the lack of a date code and the lack of any other identifying markings. Did you check for markings on all the forged pieces? For example, both sides of the steering head, both sidecar loops, front engine mount, rear engine mount, seat post forging and both axle clips.

In the holes for the coil bracket studs, thread 3/8-24 first appeared for 56 models.

The serial number (SN) boss has been altered and it also looks like there are grinding and/or file marks above it on the small round boss where the crankcase stud comes through.
Here’s an unaltered example for comparison of those areas and some characters.





Also notice on your 1 that both serifs are shorter than I’d expect for 56. And your 9s have a round back when normally they would have a straight back.

Notice the 5 under your crankcase bolt near the front. It helps indicate the left case is H-D. Other characters stamped there on H-D Pan cases include 2, 6, 9 and F but I don’t know what they indicate and my best guess is that they were done by an inspector.
The casting where that bolt is indicates the case is mid/late-52 or later. And there also appears to be a certain mark on that case which may indicate 55 or later.
The BN may tell us more and you should be able to see it even with the crankcase guard in place.

R-H case could be anywhere from 48 to 65 if Panhead but photos of it may help narrow that range down, as would a photo of the BN. And again you should be able to see the BN even with the crankcase guard in place. And even if the front exhaust pipe includes an S-piece.

Your regulator support may be the type that was introduced as of 58 models. I’d advise temporary removal to see what, if anything, is stamped on the cases. Photo?
Eric