I've been exchanging emails with members of the Dutch Vintage Club (see 'links'), who are an enthusiastic and friendly bunch. John de Kruif sent me these photos of his bikes, saying that he prefers to see Nortons on the blog, but 'doesn't mind the occasional Velo'(!)When I complained of poor starting on my '26 racing Norton, he replied thus:
"Do check the plug on your Model 25; my model 18s are very sensitive to plug condition; they 'eat' a new NGK every 1000 miles and refuse to start when it gets older; probably due to the Castrol R40 I use, no problem at all with the 16H that runs on mineral oil. Love the smell of R40 though, wouldn't miss it. The Inter is still new, took me 3 years to restore from boxes of bits, did only 30 miles yet, needs lots of fiddling. The 29 M18 looks less interesting but really is; has been worked on by a pro; lightened flywheels, slipper piston, larger inlet valve, the fastest 20s bike I've ridden so far; it doesn't vibrate and revs like hell; must have been used for racing".
The third pic of the '29 Model 18 makes a nice contrast with the flat-tank '28 version (second pic). The frame from 1929 is 3" shorter (53" axle to axle, vs 56" on the flat-tank), with provision for a saddle tank, and the valve rocker gear is more enclosed (although still not fully enclosed - that came in 1948, and on the Inter and Manx, never, even at their demise in 1962!). The clutch and gearbox remained basically the same, 3-speed Sturmey-Archer items (they changed to 4 speeds in '31, and shortly after, Norton bought the patent rights for the gearbox from S-A, and continued to use this basic design through the Commando years).
Norton kept several of their famous singles in production for decades; the model 18 started life in 1923 and ceased in 1954. The 16h began in '21 and also finished in '54, although it could be said that the 16H began in 1908, when the same engine first appeared in a belt-drive frame. A remarkable run of 46 years on a visibly similar engine.
I briefly owned an identical machine to his '29 ES2, which had been similarly tuned (I sold it to buy a supercharged Zenith KTOR, and now miss the Norton); it really went, even though it had an aluminum 'zeppelin' sidecar attached. The sidecar only weighed around 120lbs - great for acceleration, scary for cornering, as the zeppelin liked to fly!
The '27 16H pictured at the bottom is, like the Model 18, the last of the flat-tank Nortons. What had begun as a hotrod in the 'noughts and 'teens, had become a sport-tourer by this time. But, many enthusiasts prefer the flat-tank years, as the machines had a magic combination of lightness, agility, speed, and useful brakes/clutches/gearboxes. They handle surprisingly well too - my Model 25 feels as though it could safely handle another 20 hp. The long frame and relaxed steering head angle make for a very stable ride, yet the bikes can still be flung around corners with abandon.
