Billy Wolfe's Riding Spirit is now available at Amazon. The price is $0.99 -- the same as on Smashwords, Barnes & Noble, etc., but Kindle owners who would like to download directly from Amazon now have that option.
http://www.amazon.com/Billy-Wolfes-R...+riding+spirit
This story was first published in 1979, in Easyriders magazine, and reprinted in The Year's Best Horror Stories, Series VIII, in 1980. It has a 4-Star review at Smashwords.