Throttle Control Spirals with M-74B

[awander]

OK, got teh carb buttoned up with the new Durable float, and it works well...a little TOO well...

I have never been able to adjust my stock throttle control spiral to let me both open the throttle completely, and close it completely.

On my '52. I have the "New Style" controls as shown below:

124b.jpg

I also have the 50665-49 bracket for the control coil as shown above.

My M-74B has what looks like the 27260-40/27265-40 throttle control lever on it.

37.jpg

If I adjust it to where I can close the throttle all the way, I only get about 50% throttle opening when i twist the grip toward me.

Does anyone have a photo of how this setup should be positioned?

(Oh, yeah, the "working too well" comment was because I tried to cheat, and adjusted it so the throttle was slightly open when the grip was twisted away from me-I took a test run across some wet grass, and discovered this...tried to stop as I would on the street, and managed to dump the bike on my left leg.....)

[steve_wood]

Andy,

What is the total travel of your cable? Mine is about 13/16" which is enough to go from closed to fully open.

Maybe there is an issue with the barrel and spiral in the handgrip?

steve

[awander]

Hi Steve:

I will measure the travel later tonight, after the kids are in bed.

I should have mentioned in my original post that the throttle lever on the carb had been welded by someone-it looked like they did it to move the point where the cable attaches farther from the pivot point of the throttle shaft. I bent it up a few years ago to move the able attachment point closer to the center of the throttle shaft, which gave me more travel of the lever.

I should also say that the bike appears to have plenty of "get-up-and-go" even with the throttle only opening halfway-I am almost afraid of what it will be like if I get it open completely....

[steve_wood]

That modification would definitely limit the travel. Maybe just replace that part with a re-pop while you scout around for an OEM part.

[awander]

My wire moved just 7/16" from fully retracted to fully extended.

I figured I had nothing to lose, so I tried swapping the grip spiral over from the spark advance, and now I get about 13/16"!

It still doesn't open quite all the way, but it is about 3/4 or 7/8 of the way open-a big improvement!

Thanks for that measurement, Steve!

[steve_wood]

Andy,

Correcting that change to the throttle lever should get you to 100%

Let us know how it goes.

steve

[Pomike]

I had somewthing similar, and scrtched the opd noggin, but yes, it is just a matter of playing with it until it is OK. Man, I went round and round on that, 'til I remembered, it IS an old Harley. And the 1965's are about the most needing of fiddling ever. Mine would be OK, until the tanks were on, and I tried to snug everything up. It just seemed to defy reason, how much it got out of whack then. Now that I am used to it, it doesn't seem so strange. Good luck!
Mike

[Cotten]

Folks,

One diabolical confusion that I have encountered is if the setscrew for the control coil has missed its groove.
This allows for minor movement that can diminish the full throw of the throttle.

....Cotten

[awander]

if the setscrew for the control coil has missed its groove

Yeah, that would sure do it(or could, anyway).

I have 2 setscrews on each of my coils, so I would have to miss twice..

[duoglide58]

Cotten's comment on set screws was applicable on my bars. After I totaled the bike in '99, I bought some repop handlebars from V-twin. They were junk out of the box, but I had boxed them up and moved to a new place before I discovered that they had one end too short and the holes drilled in all the the biggest POS I have seen. The set screws were located on the other side of the dimmer switch such that the cable end could be placed that far into the bars.

I need to replace the bars, but I got the timer cable working satisfactory with a bunch of grinding and re-drilling.
Doug