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This restoration was 10 years in the
making. A stock 1969 Commando engine was found through the Buy-n-Sell, partially installed in a chopper
frame, but thankfully was never completed. From that start with only a complete
engine unit, sourcing for all the remaining correct and original parts got
underway. 10 years of collecting all the "right" bits culminated with a three
month restoration.
The only out work done was cadmium
plating, chrome plating and powder coating. All other work was completed in
house (painting, polishing, wheels rebuild, engine rebuild, cylinder head
rebuild with new valves, guides, springs, wiring & electrics).
The tank colour is as per the
original heavy metal flake blue, using House of Kolor flakes covered over with a
quart and half of urethane clear on an original blue Fiberglas tank.
Only
modifications from stock include 850 box section head steady, adjustable
isolastics and modest use of stainless fasteners where chrome was originally
(like the fork cap nuts, head light bolts, triple tree nut and washer, air
cleaner screen) and also stainless spokes. Maintained use of original fasteners
generally throughout.
My Engine is low miles, standard bore,
with points ignition and the original Amal carbs. The engine came with a NEW
factory warranty replacement gearbox.
This bike was last on the road in
1971. It had fallen victim to an unfortunate incident with a car and a fence. My
research indicates that the original owner bought the bike in Vancouver in 1970,
and ran it for approximately 3 months before the transmission gave trouble and
was replaced under factory warranty. Several weeks after the rebuild, a lady
driver lost control of her car and crashed through the back yard fence of the
Norton owner's house, colliding with the motorcycle. Damage was sufficient that
the bike was written off and the owner suitably reimbursed.
The remains of the
bike were passed along to his friend and it became the object of a
transformation to a chopper. When I located the bike in 1993, not much was left
intact except for a complete engine (gearbox, primary and carbs), rigidly
mounted in a water-pipe fabricated frame, with girder forks and a large 16" fat
rear tire (somebody's 1970's psychedelic dream).
The engine, despite years of
dirt accumulation, looked like it had never been apart. When I inspected the
gearbox, it was in a new housing, new shafts and gears with NO sign of ever
having been driven. The engine internals were mint and have only received
superblends, new big end shells, rings and a head rebuild.

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1969 "S" TECHNICAL DISCUSSION
Here is a brief synopsis of the "S" Model (gathered from various
sources)
"S"
Production Engine #'s start 131257 (Mar 69) to 135088 (June 70) mine is 131976
about June 1969 - Remember 1969 is THE year of all years - man on the moon and
the '69 Bonnie.
The
"S" was the first Commando with points on the end of the camshaft (more reliable
and easy to adjust) also with an integral rev counter drive - This
engineering change was noted on production engines with a new model number 20M3S
designation. The 20M3 Fastback and R model retained points behind cylinders
until September '69, eng #133668. The R ended production by September 1969 and it
is unlikely it ever received the 20M3S designation (so if you see an R with
points on cam, it may not be pucker - I will stand to be corrected on that for
sure).
The R was the initial step at "consumerizing" the
Commando - it retained shrouded front forks, fastback oil tank/side covers and
low level sausage exhaust (similar to the Atlas), but had the new fibreglass roadster 2.7gal US
sporty gas tank and pancake seat like the S. The R model ditched the Fastback
duck-tail fairing and large oblong tank. For further discussion and technical information on the "R" follow this link
The S took it all the way with naked front forks
and high level exhaust pipes and peashooters. The first roadster with low level
peashooters came in March 1970, while the S was still in production up until
June 1970.

Note, all early 68-69 Commando engines were stamped model ref 20M3 for Fastback
and R model with the points behind cylinder. For the models with points on the
camshaft, these ALL became 20M3S, which also meant that from eng #133668
all Fastbacks,
Roadsters were also numbered 20M3S. This has been a point of confusion for a lot
of people when a restorer finds an engine or bike with 20M3S and assumes it is
an S, but in reality most likely a roadster or fastback. The 20M3S model ref was
carried right through 1971 until the 200000 series 750's of 1972 or later.
-
Halo headlight
mounting which includes special top triple tree (S & Roadster)
-
naked front forks -
chrome stanchions (no shrouds or gaiters as on the Fastback and R)
-
fibreglass tail
light in silver metal flake (also used on R)
-
special chrome
chain guard rounded with cut-outs
-
chrome shrouds on
shock absorbers (all models)
-
silver painted
barrels (also R)
-
chrome trim to seat
-
high level exhaust
system (on left) with heat shields and special rear mounting bracket (only
used on S)
-
peashooter silencers
with conical ends (high level on S). These were later used upswept at low level on
the first Roadster fom eng#135140. The Fastback still used Atlas style sausage
mufflers until 1970 when from engine #139571 the Fastback MKII used the
upswept low level peashooters.
-
centre mounted oil
tank with integral air cleaner backing (used on first Roadsters also). The Fastback & R used
different units, an oil tank with integral large side cover
-
chrome fenders -
rear fender with crease for tire pump mounting
-
removable
fibreglass side covers - right side with toolkit storage, left side with key
ignition switch.
-
frame with
lightweight centrestand mounted to frame cross tube, side stand bolted to
frame tube plate
-
3 stud bolt up rear
wheel - no cush drive (great for quick starts, hard on chains and sprockets)
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twin leading shoe
front brake
-
1969 S colours were fire flake red, solid sapphire blue and later in fire flake blue
-
1970 S came in a variety of metal flake colours - red, blue, emerald green,
bronze, purple & silver, plus solid yellow (also common to roadsters of that time)
-
the small plastic
caps for the front fork pinch bolt / halo bracket nuts, I machined
replacements from Stainless.
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silver metal flake
tail light complete with red Lucas reflectors
-
serviceable centre
stand or side stand
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flexible plastic
rocker feed line (not the solid metal pipe that cracks and breaks)
-
adjustable
isolastics
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850 box section
head steady
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rear muffler
bracket mounting and back loop gusset reinforcing.
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3.25x19 front tire
in lieu of 3.00x19 original spec (not available)
Mine still retains points ignition (not Boyer) and original carbs
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seat, a reasonable
repo, shape should be more flat/fat at rear
-
exhaust headers,
mufflers and heat shield
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SS spokes
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chain guard
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