diff --git a/lib/cpBody.js b/lib/cpBody.js
index 74c0748..62d0d05 100644
--- a/lib/cpBody.js
+++ b/lib/cpBody.js
@@ -260,6 +260,9 @@ Body.prototype.velocity_func = function(gravity, damping, dt)
 	this.w = clamp(this.w*damping + this.t*this.i_inv*dt, -w_limit, w_limit);
 
 	this.sanityCheck();
+	
+	this.f = new Vect(0,0);
+	this.t = 0;
 };
 
 Body.prototype.position_func = function(dt)