Jake Robbins Vintage Engineering builds a 1320cc Norton V-twin!
The Norton 16H was the model designation for the British manufacturer’s single-cylinder side-valve machines manufactured from 1911 through the mid-1950s. These 490cc engines all had the same bore and stroke — 79 x 100 mm — which dates back to an engine James Norton developed for the 1911 Isle of Man TT 500cc Senior Class.
The 16H would become a workhorse of the British Army in World War I, and beat out a wealth of competitors to secure the War Department contract for World War II, produced as the WD16H:
“In all, eight manufacturers submitted motorcycles for the trials including Matchless, Triumph and Enfield among others and the War Office found all the motorcycles tested to be superior to the BSA “V” twins they had. But the Norton 16H stood out as the best of them all…” —Silodrome
Though some called it the “poor man’s Norton,” the 16H developed a reputation as a nearly unbreakable machine, proving itself in harsh wartime conditions over two world wars and remaining in production until the 1950s. That said, it was no speed demon, offering 14 bhp and a top speed of 68 mph.
Enter Jake Robbins, a lifelong motorcyclist who was already buying, selling, and building specials from wrecked bikes in his teens. In 2005, he started Jake Robbins Vintage Engineering, specializing in early cast lug frame repairs and girder forks like the gorgeous chrome set on the 1940 Indian Sport Scout dirt tracker we recently featured. Jake’s son William — now an accomplished welder, lathe, and mill operator — joined the company at age 16, and the father/son duo have been expanding their services:
“We have recently taken to scratch building replica vintage motorcycles for our customers…”
The Norton V-twin machine you see here began life as a 1936 Norton 16H, though when it arrived in their workshop, only the frame, gearbox, and girder forks were left. Alongside that was a J.A.P. DTZ 1320cc industrial V-twin from a two-many railway carriage, and a selection of other parts:
“The customer asked us to build up this pile of bits into a running motorcycle.”
The father/son team set to work making the big J.A.P. railway engine fit in the Norton chassis, extending the frame two inches and fabricating their own heavy-duty engine plates to hold the big lump! They swapped the original hand-crank starter for a Kubota generator hidden behind a period-correct aluminum cover they fabricated in-house, and covered up the Norton Commando belt-drive with an original chain case.
Son William, who put a great deal of labor into the build, laced up secondhand rims that had the same unrestored finish as the original machine. In fact, the pair took great pains to hide the modern touches of the build and preserve the patina of the original parts, enlisting the help of Alchemy Paint‘s Matt Bown to distress the new parts they fabricated:
“He distress-painted the petrol tank, oil tank, and a whole host of new parts we had fabricated to give the bike its handsome oily rag finish.”
All in all, this is one of the neatest machines we’ve come across this year, a father/son-built Norton V-twin that resembles a period-correct performance special right out of the 1930s, powered by a 1320cc railway engine! Below, we get the full story on the build from Jake Robbins himself, as well as more gorgeous shots from photographer Gary Margerum.
Norton / J.A.P. V-Twin: In the Builder’s Words
I have been a lifelong motorcyclist, started riding worn-out mopeds off-road at nine years old, started spannering my own bikes with the help of my older brothers…began to buy and sell motorcycles in my teens. Left school and went to work for local classic bike workshop, started to build specials from wrecked bikes.
Began to work for a vintage/veteran motorcycle engineering specialist whilst getting married and raising a family through the 90s and 00s. Started my own motorcycle business in 2005 specialising in girder fork and early cast lug frame repairs. My oldest son William joined the company at the age of 16. William has taken on a multi skill set, he is now an accomplished welder, manual lathe, and mill operator.
The workshop is split into two, with a bike build area incorporating a machine shop, and next to it is the fabrication workshop. We carry out repairs to motorcycles, restorations, custom builds and build our own design girder forks. We have built hundreds of sets of these and supplied them to some of the top award winning motorcycle customisers around the world. We have recently taken to scratch building replica vintage motorcycles for our customers…
• What’s the make, model, and year of the bike?
This bike started life as a humble 1936 Norton 16h single cylinder side valve. When it arrived at our shop all that was left of the original bike was the frame, gearbox, and girder fork. With it was a JAP dtz 1320cc side valve engine from a two-man railway carriage, a couple of 1930s unknown wheel hubs, a selection of rusty make unknown mudguards. The customer asked us to build up this pile of bits into a running motorcycle.
We set about extending the main frame by about two inches to accommodate the the motor. We took special care to fit it as low in the frame as possible with our own engine plates as it is a heavy lump! We fit a Norton Commando belt primary drive and clutch kit from NEB here in the UK. We managed to find an original primary chain case that we modified to cover it up!
We took off the original hand crank starter of the motor and converted it to drive a Kubota generator mounted forward of the engine just behind the front mudguard. Again we covered this over with a period correct aluminium cover fabricated in-house.
We fabricated an oil tank and fit up a petrol tank from a 1920s Norton model 18. We fit up a couple of Austin 7 car headlamps into a fabricated mount, selected a couple of mudguards, fabricate some period correct swaged end stays. We set about fabricating a two-into-one exhaust and fit a cast aluminium silencer.
The wheels are built up using second-hand rims to match the the rest of the rusty peeling unrestored finish of the original parts.
In order to bring all the new parts to the same condition as the original parts, we enlisted the help of Alchemy Paint, who distress-painted the petrol tank, oil tank, and a whole host of new parts we had fabricated to give the bike its handsome oily rag finish.
William built up a bespoke wiring loom and hid a lithium battery in the tool box.
We ran it up, and after some initial cam timing and oiling problems, we have it running like clockwork. It’s a joy to ride with big, smooth torque from the 1320cc 60-degree V twin. With the weight down low, it is agile and easy to handle; it has great manners and can be ridden in traffic but it is also happy loping along at higher road speeds…
I am so pleased with how this bike turned out, visually, and how it rides and would like to thank:
- Ewan Cameron of Cameron Motorsports.
- Matt Bown of Alchemy Paint.
- William, my son, who did a huge amount of the labour in this build.
- The owner for allowing me a free hand to build this and for paying the bills!
Thanks for taking an interest in what we do, I have been a fan of your site for some time — it feels motorcycle-dedicated rather than trying to sell you a ton of stuff from main dealers and influencing.