You're welcome and thanks for the photos. Steering head appears to be late-68. That was the last year for that type of frame to have a steering head lock. Notice the undrilled boss below and to the left of the hole for the steering head lock. That boss first appeared for late-68 but it was left undrilled. It was in readiness for 1969 models which had it drilled for a padlock. Also notice the screw hole. It first appeared on 1968 models and the screw secured a clamp for the throttle cable.

BTW, steering head locks are available and fairly easy to install but you’d have to check that the stem of the lower triple clamp is compatible. Your lower clamp appears to be 1969 or later because it has a padlock plate. Stamped on top of the plate you may find one or two letters followed by three or four numbers. The letter or letters will indicate approximate model year of the triple clamp so please let us know if you find anything.

On the left side of the steering head you’ll need to look a bit further back for the additional original component identifying number, aka security code, that I mentioned earlier. First look for two small round indents as per the example below and somewhere in the white area you may find the additional ID. For 1968 model frames at least three letters were used: G, H and J. (The letter I was skipped.)





Is a gusset plate welded to the front of the left rear downtube?

Re the boss that cable is bolted to, the boss was threaded as original for 58-64 Duo-Glide frames and it was used as one of the two mounting points for the toolbox. It was also threaded on some early-65 E-Glide frames even though they didn’t have a toolbox as original. It wasn’t threaded, or even drilled, as original for mid-65 and later frames. Anyway, that forging (47651-58) was used for 58 thru early-73 as I mentioned above.

On the swingarm, notice the reinforcement rib on the left axle clip. There’ll also be a rib higher up and the two ribs were officially introduced for 63 although it’s possible a few very late 62 models had them. Around 68 the lower rib was increased slightly in length and that appears to be what you have. I agree the run number is H3+. Maybe H35? If you ever have the wheel out you should find forging number 47614-58B inside the left axle clip. It will be followed by hallmark A and a die number.

On the R-H axle clip, forging number 47606-58 was used for most (maybe all?) 1958 swingarms and it then remained in use for 1959-72. Forging hallmark is the letter Q with the letters WF inside it but I do not know which company it represents. Die number appears to be in the 50s although I cannot be sure about the second character.

Generally speaking the run numbers and die numbers got higher as time progressed but the combination of numbers on some swingarms indicate the forgings were not always used in the order in which they were produced. Anyway, at this stage I think the combination of run number H3+ and die number 5+ suggests the swingarm is 1970 or 71.
Eric