? 1937 Harley Davidson ? in Williamsburg, MI

distinctively shaped rocker boxes - arrived powering a stylish all-new motorcycle in 1936. A twin-loop frame was deemed necessary to handle the 61?s increased power (37bhp in ?E? and 40bhp in high-compression ?EL? forms) while the front suspension too was beefed up, the forks switching to oval tubing in place of the previous forged I-beams. Teething problems associated with the earliest examples