Duo-Glide Handlebars, What Do I Have?

[drinner-okc]

I've been looking for a set of Duo handlebars for a while so I can adjust the timer on a custom Pan I'm piecing together.
I found a set this weekend at a swap meet. Someone must have chopped a 62-64 Duo, I got the -55 tail light w/ 6V bulb, a pair of Guide-62 Passing lamps w/ 6V sealed beams, a Jubilee Horn & the Bars.
The right bar has the complete throttle cable & pushes as it should when twisted. The left grip just spins. I removed the left spiral and there are no internals. There is no wear in the groove and no hole for a set screw to hold the cable housing in place ( I removed the horn button & bottom switch to look)
BEFORE I drill & tap a hole, is there a chance there were late 64's with auto advance (really auto-retard) timers or some other explanation?
All these parts I got were in a milk crate, left outside to die. I found the Right bar by chance helping a guy load parts he bought in his truck. I saw the bar, picked it up & was surprised the cable was so free. He said"I got the other one at home & that grip turns too." I followed him home and the parts were just laying in the weather. All the parts cleaned up pretty well and the bars have white plastic grips (not Waffles, just ribs)

[58flh]

Drinner can you post a PIC. of the parts?--It would be helpful!---Richie

[cdndewey]

I had a 72 Sportster about 35 years ago and it was first year auto advance. The left bar still had the slot for the previous years spark advance but it had a sleeve spot welded over it to make up the difference in diameter to put a grip on it. I don't rememberif it had a hole drilled and tapped to hold the spark advance cable or not, but I suspect not.

I still have the handlebars so I'll dig them out later and have a look. I have to wait for a buddy to come over and search for me as I had a hip replacement and I am limited in what I can do right now.

[drinner-okc]

Well, thanks to everybody that looked & offered to help. I'll take some salsa on my crow. I had some honey do's after work, then set up to take close-up pics & try to post. On the throttle side the screw for the control housing is under the signal switch housing. I had loosened both switches on the left side & pried them up minimally. I did not see a screw. Tonite I took several pics of the lower side (under the low/high beam switch) NO screw. Then as an afterthought carefully lifted the horn button about an inch. Dang, there was the screw under the horn button. But there still is no plunger or rollers in there. The grip just turns freely.
But I have all the parts to install a control cable for my timer. It's sad the history of why there was no timer control is lost forever. And I wish I could have gotten these parts inside before winter.
Thanks again for looking.
drinner