In 1951  only four big twin models were offered.  The EL and FL models were continued.  ELS and FLS sidecar gearing models that where offered in 1949 but not in 1950 where brought back.    production of the low compression models E and F was discontinued.

Also in 1951. new style tank emblems ,chrome plated piston compression rings and rocker arms were machined with pushrod sockets. In mid 1951 the M-74B carb was introduced along with a larger diameter pinion shaft.

 

1951 speedometer

1948-1952 speedo

1948-1952 speedo

1951 gas tank emblems

tank_emblem51_54Here are some great sources for detailed information about Harley Davidson’s 1951 Panhead

How to restore your Harley-Davidson by Bruce Palmer 111

Riding vintage website

the Jocky Journal web forum

hydra-glide.com The panhead and flathead site

The Harley Davidson Panhead service manual 48-57 rigid

1951 models
model engine type actual displacement compression factory options
EL hydra glide sport solo 61 c.i.high compression 60.32 c.i. 7.0:1 __
ELS hydra-glide sidecar twin 61 c.i.high compression 60.32 c.i. 7.0:1 S = sidecar gearing
FL hydra-glide sport solo 74 c.i.high compression 73.66 c.i. 7.0:1 __
FLS hydra-glide sidecar twin 74 c.i.high compression 73.66 c.i. 7.0:1 S = sidecar gearing

NOTE: the ” S denoting sidecar gearing will not be stamped in serial number.

1951 models available colors
paint stripes speedometer
black _____ bluish gray center. cream white mph numbers. red indicator
1951 metallic blue _____ _____
metallic green _____ _____
persian red _____ _____
rio blue _____ _____
silver _____ _____
white _____ _____