If you know about old motorcycles, you will no doubt have heard of the Norton 16H – it was an absolute icon, sold in its hundreds-of-thousands, and helped win the war. However, rewind the clock to 1911 and you will see where it all started – and that was in competition, which resulted in some special models that were available to the public. The pinnacle at the time – the Brooklands Road Special.
It all started with the 490cc 3½ hp side-valve motor that was developed by Norton in 1911. This fine thumper was installed in a motorcycle that James Lansdowne Norton (or Pa Norton as he was known) entered into the 1911 Isle of Man TT Senior. The belt-driven bike failed to achieve a place in its maiden race, but Pa Norton, never one to give up, took it back to the drawing-board, worked his magic, and entered it into the 1912 Brooklands TT with Percy Brewster at the bars. Brewster stamped the Norton name on the Brooklands bank, where he set a new class record at 73.57mph.
It did not stop there, as Brooklands racer and master tuner Dan “Wizard” O’Donovan went on to smash numerous records with his 3½ hp Norton (nicknamed the “Old Miracle”). The competition department at Norton was a force to be reckoned with, and so it made sense to allow the boy racers of the time to have a slice of the cake. In 1913 the tuned-up Brooklands models were release – a motorcycle “for those who desire exceptional power and speed for competition in a machine suitable for road work”. The Brooklands Road Special (BRS) motors were specially prepared by the factory, run-in on the track at Brooklands and certified to have exceeded 70mph for a kilo.
….. an excerpt by editor Rich Orriss …..
I recently had the honour of riding behind a BRS Norton on the Where is Anna motorcycle run in Belgium. It was an experience to behold, and here is what I wrote in the article for the event:
“I passed a few more bikes on the straights and eventually caught up with Adam, who was on his 1915 Norton BRS. This was the first time I had really heard this bike in anger, and it failed to disappoint as flames spat out of the exhaust on the deceleration, accompanied by pops and bangs as if the little Norton was trying to start its own fireworks show. The bike looked a right handful to master – with no gears, and no clutch, the only way to slow or stop is through braking, ignition retardation, and the occasional use of the decompressor. If all of the above fails, the motor simply dies, and then it is back to a running start to fire her up again. The other option – close your eyes, and hope for the best!”
So, in the wake of the Where is Anna Run, I wondered what a motorcycle like the BRS would really be like to ride. Well, lets have it. This is a snippet of one such experience, as described by David Moffat who has a fantastic 1916 BRS, and nicely explains the intricacies of the Phillipson pulley (photos taken at the 2024 Sunbeam 100 event at Brooklands).
….. an article by David Moffat …..
Earlier this year I managed to obtain an unrestored 1916 single speed Norton. The engine is similar to the first Model 16H long stroke 79mm x 100mm, but there is no gearbox or clutch. The drive is by 7/8th inch Brammer belt (should be 1 inch) and a Phillipson pulley is fitted to the engine mainshaft. This allows a limited range of variable gearing by opening and closing the pulley flanges by small amounts automatically depending on the “pull” of the engine. It can also be operated by the sole of a boot placed on the spring boss outboard of the pulley. The inner flange of the pulley is fixed to the engine mainshaft but the outer flange can move in and out on a coarse square thread cut externally on an extension of the inner flange boss and internally on the outer flange. The outer flange is held in the highest ratio position by a large clock-type spring but a heavy load on the engine results in the spring compressing and releasing the outer flange slightly allowing the belt to sink lower thereby reducing the ratio. When the engine speeds up and the load is reduced the outer flange closes up to the inner and the belt rises to the higher ratio.
If engine revs drop to a risk of stalling on a steep hill it is possible to quickly compress the spring by foot so the belt drops suddenly between the flanges allowing it to slip and the revs to pick up. As soon as the foot is removed the spring closes the flanges and the belt grips. With luck the revs have risen sufficiently to prevent a stall.
When I first had the machine the pulley was set to a high ratio of about 4 to 1. I decided to try it like that initially and was pleased on my first ride to do about 50 mph without much effort. The original handbook gives a recommendation from Dan O’Donovan (Norton’s man at Brooklands) that 4.5 to 1 is a better overall ratio for everyday use and this has proved correct as most reasonable hills can be climbed with ease and the engine is fairly easy to push start on the level (but not uphill!). Low ratio is about 6.5 to 1 before the belt slips as the flanges are too far apart. Comfortable cruising is about 40 to 45mph which it will hold up reasonable hills. I haven’t yet had it flat out…..
A small cable-operated band brake was available in period from Bowden which pressed on the spring boss and allowed handlebar operation, rather than boot sole. I may try to fake something like this but am getting more adept with the boot as I gain experience.
Riding a single speeder has been a new and fascinating experience for me. You certainly have to plan ahead and preferably try to stop only when a downhill will assist your restart. The Phillipson enables most hills to be climbed but a good run up makes it a lot easier. It is very satisfying to seek out hills and successfully conquer them, but sometimes more than one attempt is necessary. Initial failure means reversing direction of travel to a place where a restart, and hopefully a better run up, achieves success. I’ve heard some people say that the Phillipson Pulley doesn’t really work. That certainly hasn’t been my experience. Mine is an original but they are still available, now made in Australia to the original pattern.
an article by David Moffat for The Girder Club
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I originally wrote this for the Scottish Early Motor Bicycle group’s newsletter in 2015.
The Australian Philipson replicas are unfortunately no longer available.
A handlebar lever operated “brake” has since been added to my Philipson to slow the outer drum without wearing out my boot sole.
Successful in quickly lowering the ratio but not to the point of enabling “free engine” with the belt slipping at the bottom of the pulley. I’m told it is possible so experiments continue.
Thanks for the words David, it’s a really interesting art and nice to understand how it all works.