Dale's Wheels Through Time - The 1937 Harley-Davidson Knucklehead - This Model EL features an all-1937 61c.i. Knucklehead engine along with the one-year-only Delphine Blue, striped in Teak Red and edged in
Oceana Cycles - Bike: 1937 Harley Davidson UL 80 cubic inch flathead, complete engine built by Oceana Cycles. | Facebook
Bonhams : 1937 Harley-Davidson 61ci Model E 'Knucklehead' Engine no. 37E 1422