I started to build this bike in the fall of 1993 when I got bit by the race bug. I was helping fellow Norton racer, Duncan Craick, at the races at Seattle International Racetrack (SIR), and it only took a couple of races and I knew I had to race, too. I own a number of Nortons, so I selected a 1972 Combat engine and sent it off to Collier Cycle in Nashville, Tennessee, to be rebuilt and set up for racing. Sonny's mechanic, Robin, had experience building Norton race engines for people on the east coast and I had zero experience in this field.

The plan was to build the bike and be ready for the 1994 season. Duncan told me it would take a lot of time and I should make a list of things to do so I could do something every night or I wouldn't make the '94 season. Well, I knew better, and it didn't seem like a lot of work. Wrong! Duncan was right--I didn't make it out until the middle of the '95 season. A year late and a lot of dollars short. I can't say how many dollars short, for my wife might read this, and I want to build another bike this winter.

What I wanted to build was a formula 750 Norton Commando. This bike would have dual discs in the front and a single disc in the rear. Since I'm too old to think about which side the shifter is on when I'm at speed on the race track (my main road bike is a 1975 MK3), I wanted a left hand shift with a one-down, three-up shift pattern. For aesthetics I wanted the bike to be British racing green (BRG) with a Norvil tank, seat and fairing (the fairing has not been mounted yet).

I started with the rebuilt engine that was ported and flowed for 34mm Amal MK2 carburetors. I used a Megacycle 56000 cam, high performance valve springs, and a Boyer ignition, 12 to 1 compression, with the breather moved up to the timing cover. Robin chose all the specifications, for he had the experience. The only thing I asked for was to paint the cylinders BRG, not black, but they came back forest green. I guess they don't know what BRG is in Nashville.

Next I took a 1972 Commando frame, MK3 engine cradle, and MK3 swing arm and had them powder coated at Ken's Powder Coating. I chose the MK3 swing arm, because it is the strongest of the Commandos and has the best pivot assembly. By this time I had obtained a dealership with Mick Hemmings, so the rest of the parts I required came from Andover Norton or Mick Hemmings.

One note on powder coating the engine cradle: Do not powder coat around the bolt holes, or if you do, remove the coating after powder coating. I ordered 1/4" longer stainless engine bolts from Mick Hemmings. When he asked me why, I told him I had powder coated the cradle and needed longer bolts. He told me the bolts would sheer immediately. Again I knew better, figuring my coating was better than what Mick had used. The second time I hit 7000 RPM, I got a horrible vibration. I sheered two of the back engine bolts, took out the rear isolastics and removed the gasket between the inner primary and the engine (just the gaskets, not the bolts--they are held in place by tab washers). I'm learning to listen to the experts.

I took new MK3 transmission cases, new bushings and shift linkage with the existing gears, shafts and other pieces from the original transmission and built the left-hand shift, four-speed transmission I would use. The MK3 cam plate is identical to prior Commando cam plates except for the neutral indicator lobe. Because I had a neutral switch installed, I used a MK3 cam plate. The neutral light is yet to be installed. The MK3 has the shift pattern of one down and three up that I wanted, but it achieves this with a set of gears in the primary case. Since I was going to use rear sets of my own design, I decided to bring the shift straight through the primary case and reverse the shift lever, which would provide me with the desired pattern.

I'm running a belt drive primary, so all I had to do was have a bushing welded to the outer primary case and drill a hole in the inner case for the shifting shaft. I used an old set of 750 primary cases and had Keith Johnson do the aluminum welding and build the shifting shaft. We made the shaft from a MK3 shaft and welded the end of a right-side gearshift pawl on the end to accept the shift lever. I drilled the air holes in the outer primary case and removed the inner boss that the original fixing bolt went through. The shifting shaft comes through the inner and outer primary cases at a slight angle just about where the bolt went. I then drilled and put Helicoils in the two locating holes in the inner case. Then I drilled out the outer case and use stainless allen head screws to secure the outer case to the inner case. The inner case fixing bolt was modified and moved to where the MK3 bolt would normally go since I'm using a MK3 engine cradle. There are three air holes drilled in the inner case just in front of the flange around the counter shaft sprocket, which provides cross ventilation. The patterns for the outer case air holes were chosen to cover up a dent in the case from the old foot peg (real scientific).

The front end consists of Norvil 11 1/2" cast iron discs, Matching sliders, AP Lockheed calipers and braided lines of my design. I use an AP Lockheed .7" master cylinder, standard Norton fork bushings and components, Progressive springs and Franks forks. The hub is Norvil with an Akront WM3 shouldered rim and polished stainless spokes. The drilling of each disc removed 1/2 pound, or 1 pound of rotating weight in the front end.

The rear wheel is a standard MK3 hub with the same rim and spokes as the front wheel. I modified the disc carrier for the Norton-to-Norvil front wheel conversion to fit the rear hub, allowing me to run the same Norvil discs front and rear. I'm using an AP Lockheed 5/8" master cylinder with a rubber hose acting as the remote reservoir and used the same idea as the MK3 rear brake linkage to build mine. In fact, I modified a MK3 rear brake lever and used some of the standard parts. I built the rear caliper mount to fit the same AP Lockheed calipers as the front brakes.

Because wider tires are available for 18" rims, some vintage racers like to run them on the rear wheel. I read somewhere that the Commando frame was designed to use 19" wheels. Since I wanted to use the same tire on both front and back wheels, I chose the 19" rim for both.

The brakes on this bike are fantastic--I can raise the rear wheel off the ground under hard braking. In the WMRRA race school during the braking exercise, they told me not to use the rear brake since the rear wheel was off the ground and might get me into trouble during a race. In fact what I did do is de-just the rear brake so it barely functioned for the first three races. With all my years of road riding, I found it hard to break some of the habits I had learned--rear braking being one of them. I have since re-adjusted the rear brake back to what it should be and am working on learning when and how to use it.

The shocks are Koni dial-a-ride shocks with both dampening and preload adjustments. I'm running with the Konis on the middle settings for both adjustments and with 30-weight fork oil in the front forks. This seems to work well for me, but to be honest, I may not be going fast enough to know. When I start to get consistent with my entry speeds and use the same entry points into turns, I may play with my suspension.

I run the same tires both front and rear--Avon super venoms with 100/90 V19 race compound. In the WMRRA race school they stated that for optimum tire performance, the tire pressure should increase 10% from the starting pressure after it heats up. If the tire pressure increase is below 10%, reduce the air pressure. If the increase is above 10%, add air. I have found that 30 pounds in both front and rear works the best.

Since I have a bad neck and can't get down on the tank anyway, I chose to use the same clubman black chrome bars that I use on my street bike. If you ever see me racing, you'd think I was going for a Sunday cruise with my semi-upright riding style. It's not quite true that I can't get flat down on the tank, but if I do, all I can see is my gas cap. The two speed Magura throttle set on the regular setting works well. I had to build my own throttle cables with the Magura and the MK2 Amals.

I run with an oil pressure gauge and like it a lot. It lets me know when the engine starts to wet sump (This is a long story that I'll save for another article, since I have not solved the problem yet). I had the braided oil lines made using two standard Norton double banjos. The oil pressure gauge is taken off one side of the left banjo.

I saw a picture of a 1976 Norton Commando with foot rest plates painted black in the center, so I painted mine the same. The fiberglass tank, seat, side covers and front fender were ordered with a BRG gel coat. The logos and pin striping are actually decals that I have made up for me at a local sign shop. In the pictures, only one side of the tank has pin striping, since I wanted to see what it would look like both ways. I also had some difficulty applying the tank pin striping, but I've since learned how to apply them. Both sides of the tank are now pinstriped.

The black chrome exhaust system is from RGM in England. It is expensive (it's all expensive!) and works well, but as I go faster, I find I scrape the exhaust pipes. Mick Hemmings makes exhaust pipes that tuck closer to the frame, so I'm working on getting plain exhaust mufflers from Toga and exhaust pipes from Mick Hemmings and then having them black chromed over here. Hopefully, it will be cheaper and they will work better.

Most fasteners, bolts, axles, etc., are stainless steel. I like the looks and durability of stainless, but there are two concerns. First, anti-seize must be used on all stainless steel bolts, for they will weld together under pressure. I have not had any problems since using anti-seize (by this statement you should be able to read into it that I learned this the hard way also). The other concern is drilling stainless nuts and bolts for safety wiring (something you do a lot of on a race bike). Stainless steel work hardens and is a bitch to drill. I use cobalt drill bits, cutting oil, and a drill jig and still only get two or three holes per drill bit. You look after a race bike more than a street bike, so stainless may be overkill; but I like it and will use it on my next bike also.

The electrical system consists of a very small 12-volt battery (YB4L-B), a Lucas 180-watt three-phase alternator, a rectifier and two zener diodes. The 180-watt three-phase alternator is great for a road bike, but is definitely overkill on a race bike. I have plans to replace it with a standard alternator. I'm using a Boyer electronic ignition with a Harley 12-volt high-output coil. This winter I am also going to replace the rectifier and zeners with a Boyer power box which will allow me to run with or without the battery.

This bike has been fun and very educational. It has taken a lot of hours and some serious money, but after only a couple of races, it has more than paid me back in the pleasure I receive. I'm dirt slow on the track, but I do have a smile from ear to ear--and that's what vintage road racing is all about.

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