Triumph Ariel Square 4 motorcycles for sale

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Triumph : Other 1958 ariel square 4 beautifully restored by marque expert extensive history

Triumph : Other 1958 ariel square 4 beautifully restored by marque expert extensive history

$34,900

Santa Monica, California

Year 1958

Make Triumph

Model Ariel Square 4

Category Standard Motorcycles

Engine 1000

Posted Over 1 Month

Beautifully restored by a renowned marque expert! 1958 Ariel Square Four Engine Number: CNML1879 Frame Number: CDM1809 In 1928, engineer Edward Turner was shopping a new motorcycle design to English manufacturers. BSA turned him down, but Ariel was interested. The engine was an unusual four-cylinder. V-twins and inline fours, set both lengthwise and across the frame, had been used previously but Turner’s new design had two vertical twins sharing a common crankcase. The cylinder barrels were cast as a unit in a monobloc design. Their two crankshafts were joined by a flywheel and rotated in opposite directions. By having the two pistons of one crank at top and bottom dead center and the pistons of the second shaft at half stroke, the design was ingeniously compact and the firing order made it practically vibration free. The Ariel Square Four 4F made its debut at the 1930 Olympia Motorcycle Show featuring an overhead camshaft 500cc with a hand shift for the Burman gearbox, which was integral with the crankcase. Overhead camshafts and unit construction were well into the future for most firms, so Ariel was a real pioneer. Few knew then that the bike would become a legend of the British industry, both for its performance and dependability. The latter was underscored by the Square Four’s widespread used in the British law enforcement community. Improvements were continuous during the Square Four’s 28-year production run. In 1932, the 4F was taken out to 600cc, although the 500 remained available. The next year, a 4F 600 fitted with a supercharger lapped the famous Brooklands speed bowl at 110 miles per hour. The 4G was introduced in 1936 with a new 996cc overhead-valve engine. To accommodate the larger displacement, a new crankshaft was set in a much stronger crankcase. These years saw the British economy recovering in the run up to World War II, and Square Fours were seen on the road more often, where they were known as the “Monarch of the Multis”, referring to their multi-cylinder engines in a sea of British singles and twins. By the immediate post-World War II period, the 4G had a plunger rear end and telescopic front forks. Further refinement was added in the form of aluminum cylinder barrels when the Mark I began production in 1949. Soon after WWII, an American Air Force pilot began flying back and forth from his base in California to bases in southern England. While on one of these trips, he discovered the Ariel Square Four and was smitten. He purchased a bike to run around the country lanes while in England and then, with a little room to “spare” on the return flight, he snuck the bike on and brought it back Stateside. Enjoying the bike in the Southern California backroads was the perfect setting and soon friends and colleagues became interested in the quirky British ‘four’ in a time the American competition offered nothing but archaic pre-war designs. And so a little side business developed with frequent trips to the UK and return flights with undeclared Ariel motorcycles and an abundance of parts filling the spare room of the planes. This continued on for many years, and the gentleman in question – let’s call him Chuck – made use of his engineering background and restored and maintained many Ariels. Practically starting the Ariel Owners Club, he remains an active member to this day. Retiring in 1990, the hobby continued on and to date, he has rebuilt 107 engines for himself and clients/friends and restored many bikes from the ground up. To say he is an expert of the marque is just scratching the surface. His knowledge is encyclopedic and having restored so many engines, understands every pitfall of the unique design and precisely how to prevent engine failure. Tricks to rod bolts (a well-known weak point of the engine), rocker arms, crank bushings, valve guides and springs ensure engines with great power, superb reliability and great longevity. The bike on offer is one of Chuck’s personal favourites, a 1958 matching engine, frame and gearbox numbers bike in the ever-stylish black colour scheme, which sets off the chrome accents so well. Originally brought in to the US in 1966, the bike was sold to a fellow pilot, who enjoyed the bike until a couple of years ago when it was placed in storage. Having survived 3 divorces and 20 some odd thousand miles, it was time for a full spec ‘Chuck’ restoration. Having just been completed, the bike is offered in stunning condition, with zero miles on the odometer of the rebuilt speedo (for $525!) since a total restoration. The bike was completely dismantled and every part was rebuilt, refinished and restored. Every part on the bike is original to the machine. At the heart of the machine is one of Chuck’s fully rebuilt motors. Rebuilt from the crank up and featuring all of his tricks and nuances, the engine is in fine tune with strong power, and sounds utterly fantastic with the cocktail shaker exhausts originally on the bike from the ‘60s, more like a Ford Flathead than any motorcycle I’ve ever heard. With the internal tweaks and oil cooler it runs well and at proper running temperature whilst doing so. Brakes and all suspension parts were restored and a new correct wiring harness was installed. The bike retains its hard-to-find original Lucas headlamp. Cosmetically the bike is exquisite throughout. The only departure from factory spec, apart from the exhausts, is the removal of the headlight cowl. This was a common modification, made in period, to give the bike a more sporting look over the standard, more gentlemanly appearance of a shroud housing the speedo. This is how the bike came over in ’66 and remains so. The frame was powder coated, and all parts painted, coated, rechromed and refinished. It is a truly ground-up restoration, where nothing was untouched, eligible for concours d’elegance prize or museum display, shame as that would be for such a great running example. Here is a great opportunity to acquire a fantastic riding Ariel Square Four built by a true aficionado, accomplished engineer and one of the world’s leading marque experts. It is ready to show, or ride anywhere and be enjoyed.

Trim Beautifully restored