I have had my 1988 venture for a year now and have had no issues. While riding it yesterday I shifted into 4th gear and a clicking sound started. It is like something is not engauageing but it still shifts into 4th and drives. Gears 1-3 don't do it just in 4th. took the side cover off and all seemed normal. Just am at a loss. Love this bike just don't know what to do.