Gear heat treatment

[Mykneesbehurtin]

My buddy has a 2021 Freewheeler and the transmission self-destructed last week. He doesn't ride hard, pull wheelies or anything that would cause it to break gear teeth. So here is my question, does anyone know what the Rockwell should be on gear teeth. We have a Rockwell tester at work and he wants me to check the hardness of his busted gears.

 

[Jack Klarich]

Good question Steve, I dunno if I ever saw the published number

I do know HD has had ongoing problems with 3rd gear blowing out

 

[Mykneesbehurtin]

A friend of mine makes race parts for 900 and 1000 Kaws, specifically the center pin for the crank shaft. They are made from 8620 steel then surface hardened for wear but the centers remain soft so they will bend instead of breaking. So my thinking is this would be true for gears also. When I say bend they don't bend more like give a little ,this keeps them from shattering like glass.

 

[Mykneesbehurtin]

Good question Steve, I dunno if I ever saw the published number

I do know HD has had ongoing problems with 3rd gear blowing out

The dealership that has his trike said they have 2 other trikes up there with same issue.

 

[Jack Klarich]

Here is 1 example of a 3rd gear gone bad, you can Youtube moonshin HD on what a bad gear set looks like also

 

[Jack Klarich]

Here is another

 

[Mykneesbehurtin]

Thats what his gear set looked like.