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A 1971 Norton Commando 750 Print E-mail
Monday, 06 March 2006



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When Gary first went to look at this bike, he knew it would need a little work, but it was all there and seemed to ride fine. A lover of fine English machinery, Gary made the deal and took it home. It wasn't until he got it on the road that it started acting up. It rarely started, and when it did, it would only run on one cylinder. After some preliminary troubleshooting, the compression test found almost no compression in one cylinder. As ol' King Henry VIII would say, "off with 'er 'ead".

Upon further investigation, Gary found a fascinating assortment of valve gear, BSA, Triumph, Norton, Honda, Jawa - you name it, it was in there. The springs on the left intake were BSA or Triumph, the right exhaust was Norton, the rest were who knows what. Each valve had mismatched keepers with one being a decent fit and the other sticking up about 100 thou past the top of the valve. Logically thinking, the compression loss could have been a result of the protruding valve keepers hitting the adjusters and keeping the valves partially open. So, Gary installed new Norton springs, keepers and collars and put the head back together. The barrels and pistons looked good, and passed the varsol test, so the head went back on. Gary figured he'd be riding again in no time.
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Gary figured wrong. The bike still wouldn't run reliably. Thinking it was some quirky Norton thing; Gary enlisted the help of local Norton guru, Derek Wilson, to help out so he could get it running and resell it. Gary had always been a BSA and Triumph guy, and had never had trouble getting a bike to run. He'd had enough of this Norton crap and he wanted out.

Derek got it running almost immediately and pointed out that, with a little bit of work, it could be made into a decent bike. At least Gary could then get his money back out of the deal. The bike came with a Suzuki front end which was replaced with the correct Norton hardware. Then came the first of many calls from Derek. With the bike on the bench, and the tank and seat removed, it was obvious that the frame was bent. Since the headstock was 'modified', it was quickly determined that a new frame was needed. Just as with the valve train fiasco, the tear down revealed many more 'shortcuts' from the previous owners. Gary had a dilemma: to continue spending money and keep the bike for himself, or cut his losses and sell it as a basket case.

Gary had enough cash into the bike that he couldn't turn back now, so he managed to find a frame; a modified '71 that had the rear loop hacked off. No problem; they just cut the rear loop off of the original frame and welded it to the new one. The frame, along with a box full of parts, were sent out for silver powder coating, another box of parts was sent out for black powder, while a third box was sent out for chroming.

Gary was concerned with the bike's stopping ability with a drum on the front, so he made a deal with his friend, Rob Lees, to trade the original drum front end for the disk setup and a pair of Hagon rear shocks. A local vintage Norton racer was interested in the spare Suzuki front end so a trade was made, for a pair of Akronts rims that were laced to late model hubs with stainless spokes.

With the help of a couple of local Nortoneers, the reconstruction began. Gary was a little worried about their frequent use of the phrase "it's not my bike" whenever something bad happened. He was always taught to say "sorry" when he broke the other kids toys.

As the build progressed, they installed one of Derek's Nissin caliper front brake upgrades, stainless oil and fuel lines, a 520 O-ring chain conversion, stainless muffler brackets and many other changes to improve handling, reliability, safety and esthetics.

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Finally, after almost three years in his possession, it was together and almost ready to go. Derek and his father had been working on the finishing touches one night in order to have it ready for the annual Norton Owners Elephant Run. Just when Gary thought all was good, he got another one of 'those calls'.

It seems the bike started up OK and ran well, but then there was a sudden "clack-clack-clack", and it quit. Out came the motor, one more time, and it was discovered that the cam followers were hanging up inside their barrels. At some point in the past, a cam follower had disintegrated, and chunks of hardened steel had caused havoc inside the running engine. There was damage to the camshaft, the connecting rods and the inside of the cases. The previous owner, in typical fashion, replaced the broken cam follower, ignoring all the other damage. Obviously, a complete engine rebuild was now necessary.

The original bores were intact and only in need of honing; the crank and the crank journals were still in good shape. They ended up replacing the pistons, rings, connecting rods, and big end shells with stock parts. New Superblend crankshaft bearings, a 2S cam and mushroom head tappet adjusters were installed. The original timed crank breathing setup was ditched, in favour of a system that keeps crank pressure at a slight vacuum, thus eliminating oil leaks. With the engine together, back in the frame it went. The whole engine build ended up taking less than a day, with everything going strangely smooth.

Now it's done, well, almost done. OK, so it will never really be finished, Gary admits, but at least he can ride it now. MMM
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Photography Jonathan Bielaski, Light Imaging

Specifications
Owner: Gary Collins
Make: 1971 Norton
Model: Commando 750
Builder: Derek Wilson/Gary Collins
Time: 8 months

Engine
Year: 1971
Builder: Derek Wilson/Gary Collins
Displacement: 750cc
Cases: Modified Norton
Heads: Stock rebuilt Norton
Lower End: Norton with Superblend bearings
Carburetor: Re-sleeved Amal 930 concentrics
Ignition: Boyer Bransden electronic
Exhaust: Stock Norton Roadster

Transmission
Year: 1971
Builder: Norton
Type: 4 speed
Case: Stock
Clutch: Stock multiplate
Primary Drive: Stock chain

Frame
Year: 1971
Builder: Norton/Derek Wilson/Gary Collins
Rake: Stock
Shocks: Hagon
Modifications: Ballistic sidestand lug, additional bracing for strength

Front End
Year: 1975 Norton
Builder: Norton
Type: Stock
Modifications: Nissin caliper & Wilson adapter plate, stainless brake line, sealed wheel bearings
Painter (powdercoater): Achord metal, London, ON
Restoration: Derek Wilson/Gary Collins

Wheels
Front Tire: Metzeler ME33 Laser 19"
Builder/Manufacturer: Akront Alloy with stainless spokes and Norton hub

Rear Tire: Metzeler ME33 Comp K, 18"
Builder/Manufacturer: Akront Alloy with stainless spokes and Norton hub

Essentials
Gas Tank: 1973 Commando - steel
Fenders: Front - modified Suzuki Savage
Rear: Stainless Norton
Seat: Corbin gunfighter
Handlebars: Euro
Headlight: Stock Lucas
Taillight: LED board in stock housing

Extras
Sparx high output alternator & solid state rectifier
Stainless fasteners throughout, including axles
Wilson O-ring chain conversion

Last Updated ( Saturday, 29 March 2008 )
 
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