No.........it's probably #415 chain.........available at www.ikesbikes.com or www.mopedwarehouse.com or at stores that sell heavy duty BMX chain.
But the #420 chain shouldn't bind unless it is very large and binds at the front sprocket or against the hub at the rear.
You should probably replace front and rear sprockets if it has a lot of miles. don-ohio (:^)