Hile changing the axle joint i noticed a crack in the ring it broke off now i have a thumping petal it pulls horibly to the left an then the petal bottoms out
What is the proper name of this part so i can track one down???

 

Tone ring or reluctor wheel.

 

Thank you very much
Now where can i get one an are they part of the axle can they be changed??

 

They can be tapped off with a hammer.

Grab one from your favorite JY.

 

Yeah, just pull a used axle shaft and press the tone ring off, then you'll have an extra axle shaft for trail side repairs.