View Full Version : Piston Pin Retainers

05-11-2007, 03:18 PM
I have a 1965 FLH, that is using "C-clip" retaining rings for the piston pins. According to the manual, this is not what was used, originally. To remove the clip, I found that using a pair of snap-ring pliers and compressing the two ends of the "C-clip" together, was not enough to remove it, so I had to overlap the two ends to further compress it, to get it out.

I have heard all the horror stories of not re-using old clips. Are these the correct clips to use, or is there something better?

Is there a better way to install them, than using snap-ring pliers, and overlapping the two ends?

Any tips would be appreciated.


05-12-2007, 06:03 PM
I just went through this with my '52 Chief. I used my Dremel Moto-tool to round off the horns of the clip at the eye holes. Then I made sure to install the clip such that the main body of the clip (away from the ends) is inserted first.That reduces the clip diameter and the overlap at the open end is reduced. If you get one eye of the clip still not in the groove after this, you can tap it in with a hardwood dowel. Always using new clips is cheap insurance.

05-13-2007, 11:41 AM
Thanks. That's a good idea. I don't understand the failure mode. Do the retainers break, or do they just work themselves out of t he groove? They are made from spring steel, so I don't understand why there would be a problem, reusing them.

Also, I spoke with a retired Harley dealer, and he said to purchase the retainers from Harley, not to get them from say an auto parts store, and never reuse them. He said the cost is so cheap, so why risk big money problems, later.

When installing the piston pin, should I install one retainer, first, then make sure the pin is not resting against it, when I push it in?


05-13-2007, 02:55 PM
Over the years I have built many race engines and I always used to fully float the gudgeon pins in these motors so now when I rebuild vintage engines I use the same procedure and you don't have any circlips to worry about.
Basically the gudgeon becomes a nice free sliding fit in both the piston and the con-rod eye and is retained by teflon buttons at either end. A small hole must be drilled in each button to let the trapped air escape, as it expands, as the engine heats up.
I'm sure you have an engine builder in your area who could show you the in's and out's of this system but as far as I'm concerned it's the best way to go.

Regards Tommo

05-13-2007, 08:12 PM
Thanks Tommo.