A quick look at kicker gears!

So, it’s been awhile since I’ve posted anything, life’s been busy enough that the website got neglected :-(. However something that I’ve been interested in came to mind as a result of a swap meet find.

Went to the Chesapeake AMCA meet at Upperco Md a couple of weeks ago and found a 4 speed kicker gear in a box of stuff.

Looking at the pictures I’ve posted, it’s 3 views of an Knuck/Pan era kicker gear in Pristine never used condition. Granted it shows its age, but no wear. So, a little background on how these gears were made. Some of you may already know this, but hang in there.

The second image shows the steel backing plate and it’s obvious copper plating. When Harley wanted to harden a part of a piece, but not all of it, they would copper plat that part of the piece that they wanted to remain unhardened. They placed the piece in an heat treating oven, immersed in Bone Charcoal and baked the part for a proscribed time. The longer it was baked the deeper the charcoal diffused into the part and the deeper the case hardening of it. However, the copper prevented the charcoal from diffusing on the plated areas.

The first photo shows the other side of the gear and a small shiny area of the backing plate behind a portion of the gear. The third photo shows this area a little more clearly. Their objective was to create a hardened area behind the portion of the gear where the plate was pushing the mainshaft kicker gear out of mesh with our kicker gear we see here. That plate had to be hard or else the mainshaft kicker gear would chew up the plate and eventually jam the two gears.

I’m sure many of you have seen this kind of damage with cheap knock off gears from far off places. Now there are suppliers out there that do make a kicker gear with the correct properties to perform satisfactorily, but they tend to be pricey. Hey, not knocking it quality has it’s price. However, If I can find a NOS gear in a junk box at a swap meet for $10.00, I’m going to buy it!!

Anyway, I just thought that folks out there might be interested in this neat find, and a little of the back story of why some Harley parts sport the nifty copper plating. Original crankpins and Mainshafts are other items where you could see the copper plating, there to keep the threads from being too brittle from the hardening process.