Tagged: square four

Sophisticated Performer: 1957 Ariel Square Four for Sale

1957 Ariel Square Four L Side

A vintage luxury sports machine, the Ariel Square Four had, as the name suggests, four whole cylinders at a time when most motorcycles of the period had just one or two. Automobile components can get away with being heavy, but over-engineered solutions in a motorcycle application mean significantly reduced performance and, for years, four-cylinder engines weren’t compatible with twin demands of light weight and reliability. Inline fours can be tricky to package into a motorcycle, particularly when configured longitudinally, as was common before the Honda CB750. But the Ariel uses an interesting “square” format that features a pair of parallel twins, complete with a crankshaft for each. Not only did this solution offer up the power and smoothness of an inline four, the very compact design meant it could be squeezed into existing frames meant to house a parallel twin. No surprise, as the design was originally intended for BSA.

1957 Ariel Square Four R Side Rear

The first generation of Square Four displaced 500cc with a bump to 601 for increased torque, so riders using the bike as practical transport could more easily drag the weight of a sidecar around. That early overhead cam design had issues with overheating, as the square four configuration naturally has a hard time getting cooling air to the rear pair of cylinders. Suzuki’s later RG500 engine used liquid-cooling to get around this problem, but that was obviously not an option here.

1957 Ariel Square Four Dash

The engine saw a complete overhaul in 1937 with a shift from overhead cams to cam-in-block and pushrods, but a big jump in displacement to 997cc.  In 1949, the iron head became aluminum for a huge savings in weight and the version seen here is the final iteration, with four individual exhaust pipes, instead of the earlier pair of siamesed parts that make the bike look like it’s powered by a bulky parallel twin.

1957 Ariel Square Four Engine

From the original eBay listing: 1957 Ariel Square Four for Sale

Up for sale is a restored Ariel Sq4 This bike was completely restored 10 years ago and sat in a collection for 5 years.  I bought it and meet the person who restored it in Mass. He is good at what he does and the bike still shows very well. All the miles were put on by me, last being a 50 mile ride 2 years ago. The bike has been started and ran in the last few months. It will start right up and operate very smooth. There are no known problems. The restoration was both mechanical and cosmetic at the time. Buyer will be responsible for transportation from Pgh PA.

I’m assuming “Pgh” is Pittsburgh in this case. There’s very little time on this auction, with bidding up just north of $16,000 and the reserve not yet met.

1957 Ariel Square Four Tank

So what’ll she do, mister? Well that nearly full liter of displacement gave 45hp and the bike weighed a surprisingly svelte 425lbs, so the Square Four could very nearly “do the ton.” But while bikes like the BSA Gold Star were about ultimate performance, the Square Four was about the way in which it delivered that performance, and the smooth relaxed power and sophistication was really in a class by itself from the bike’s introduction in 1931 until it was discontinued in 1959, a remarkable production run for any motorcycle.

-tad

1957 Ariel Square Four R Side

Hip to Be Square: 1951 Ariel Square Four

1951 Ariel Square Four L Front

By the 1970s, four-cylinder powerplants were dime-a-dozen in the motorcycling world. Formerly found only in high-end exotic machines like this Ariel Square Four, they’d become a characteristic of the generic “Universal Japanese Motorcycle.” But in the 1950s, a four-cylinder engine was something to brag about.

These days, inline and V4 configurations are common, but the Ariel used an unusual “square” configuration not often seen outside two-stroke race-replicas like the Suzuki RG500 Gamma. As you’d expect, the square four is really a pair of parallel-twins, each with its own crankshaft, geared together and sharing a head. This makes for a compact motor that slotted easily into existing frames, but one with the inherent cooling problems that result from limited airflow to the rear cylinders.

1951 Ariel Square Four R Engine

Introduced in 1931, the engine was significantly overhauled in 1937: in a seeming step backwards overhead cams were changed to pushrods, but the heads and barrels were changed from iron to aluminum and displacement increased significantly from 500cc’s to almost 1000. Reliability was increased and the character suited the bike’s mission: while performance was impressive with over 90mph possible, it was smooth and very torquey, a “gentleman’s express.” Production continued until 1959.

1951 Ariel Square Four R Rear

Today’s example looks to be in very nice cosmetic condition, but has been off the road for a while and will need some work to set it right.

From the original Craigslist post: 1951 Ariel Square Four for Sale 

You won’t see one like this every day… A MAGNIFICENT 1951 Ariel Square four 1000cc with a 1954 engine (four pipe manifold). Check the photos. One of the world’s best motorcycles ever from that decade. Much in the way of papers, manuals and history information available. After its long rest it will require some freshening before an outing, but it’s all do’able. The price has been reduced to $16300. Call for further information and an appointment to view.

This vehicle is currently Cal licensed , clear titled, and on non-op status.

The seller is asking a bit less than I’ve seen for nice Square Fours recently, and the mention of it being “reduced” suggests that interest has been low. I’m wondering if the updated engine is causing issues for fans of originality, or if the possible headache of getting this bike on the road is putting buyers off. The seller doesn’t mention why the change to the later powerplant was made, but certainly the performance benefits should be worth the update for fans of function, and the later exhaust manifold shows off the bike’s four-cylinder-ness proudly, whereas the original could be mistaken for a big parallel twin. The seller also doesn’t mention exactly what it might need, if anything other than usual, to get it back on the road as “its long rest” isn’t really quantified, but cosmetically, the bike appears to be complete and in good shape.

-tad

1951 Ariel Square Four Front

All-Original GP Machine: 1982 Suzuki RGB500 Mk7 XR40 for Sale

1982 Suzuki RGB500 R Side

Ridden by such luminaries as Barry Sheene and Randy Mamola, the two-stroke Suzuki RGB500 was eventually developed into the dominant machine you see here, but it went through a significant evolution following its introduction in 1974. As you’d expect, the bike always had power to spare, but high speed handling was suspect at first…

1982 Suzuki RGB500 R Side Naked

By the time the 1982 bike rolled around, Suzuki had moved to a “square” 54mm x 54mm engine for a grand total of 495cc. It was far more reliable than previous iterations and featured the same stepped cylinders seen on the RG500 Gamma road bike that had the rear pair of cylinders raised up slightly higher than the front pair. With a dry weight of 292lbs and 120hp, the bike could reach speeds of up to 170mph, which is pretty terrifying considering the tire technology of the time.

1982 Suzuki RGB500 R Side Grip

Fascinating details seen in the photos include the square-four’s complex throttle cable assembly and the anti-dive front system on the front forks.

From the original eBay listing: 1982 RGB500 Mk7 XR40 for Sale

This is not a street bike folks, this is the real deal, A real factory Suzuki GP road race bike… This bike has the stepped square 4 motor with magnesium crankcases, magnesium carburetors, and dry clutch… The Chassis is loaded with magnesium, Titanium and Aluminum, stuff you would expect to find on a factory race bike… First year of “Full Floater” monoshock suspension… Chassis number 42 motor number 49… Bike is in unrestored, excellent condition, just as it rolled off the race track in 1982… This bike from part of the team Heron Suzuki stable, bike has been museum store in Japan since last raced… these bikes are tad more rare than a TZ750 and much more powerful… It is the perfect bike to dominate vintage racing and is eligible for the “classic TT” in Phillips island This is a rare opportunity to own a real factory GP bike, don’t let it slip by, you’ll be sorry if you do…

1982 Suzuki RGB500 R Side Front

With a beautiful period paint scheme and tons of rare, race-spec parts, this bike may not have been ridden by any famous racers to any notable victories, but it’s also available at a price much lower than you’d expect to pay for one of those machines. Bidding is just north of $25,000 there’s a ways to go until we hit the $65,000 Buy It Now price. It’s in impressively original condition and would make a stunning collector’s piece, but hopefully, the rise in popularity of vintage racing will see this bike returned to the track.

-tad

1982 Suzuki RGB500 L Side

Vintage Grand Prix: 1982 Suzuki RGB500 for Sale

1982 Suzuki RGB500 R Front

When Suzuki dipped their toe back into Grand Prix competition in the early 1970’s, it was with a production-based, water-cooled two-stroke twin from the T500. But while that bike did see some success, it was clear early on that a ground-up redesign would be needed. What followed was the twin-crankshaft, disc-valved square-four format that we all know and love from the RG500 Gamma road bike. In racing trim the RG500 was extremely successful in the hands of riders like Barry Sheene and variations the bike were a dominant force through much of the 1980’s.

1982 Suzuki RGB500 L Side

Of note are the air-assisted anti-dive forks, something that I’m sure works well here or they would never have been included, although roadgoing versions are of dubious value. Also of note is what appears to be a coolant expansion tank on the inside of the front fairing, something I haven’t seen on other examples.

1982 Suzuki RGB500 Dash

This one comes to us from our new best friend Gianluca over in Italy and is clearly photographed, something you’d expect when we’re looking at so rare a machine, especially considering an ex-racebike could be in very tatty condition.

1982 Suzuki RGB500 L Grip

From the original eBay listing: 1982 Suzuki RGB500 for Sale

model year 1982

VIN 10003 
Engine 10072

This is an Iconic model and does not need any presentation. The bike advertised has a very low VIN number, it was rebuilt 15years ago and rarely used, just paraded, it comes also with original cylinders. This is the bike bought and used my Riondato (Italian Champion in the 350cc class) beetween 1982 and 1984 in the Italian and European Championship including the 200miles of Imola. 

Race and collect! Bulletproof investment.

Bike is currently located in 33080 Roveredo in Piano, Pordenone, Italy but I can get them delivered all around the World at cost, no problem.

1982 Suzuki RGB500 Clutch

Clearly photographed and in beautiful, but well-used condition, what more could you ask for in an eBay listing? The original listing also includes some period photographs of the bike in action, although the paint scheme has changed since then to a more traditional Suzuki blue-and-white design, a decision that works for me: racebikes get crashed, painted, re-painted, torn apart, and rebuilt, so “originality” is pretty relative anyway.

-tad

1982 Suzuki RGB500 R Engine

Sophisticated Vintage Brit: 1952 Ariel Square Four for Sale

1952 Ariel Square Four R Front

The motorcycling industry prior to the 1960’s was centered on single and twin-cylinder machines, and, at a time when simplicity equaled reliability, Edward Turner’s compact four-cylinder design would have seemed extremely exotic. Prior to the Lancia Aurelia’s introduction in 1950, car and motorcycle engines used “inline” formats almost exclusively, and although inline fours work fine in automotive applications, they can cause packaging, as well as cooling, problems in motorcycles.

Originally rejected by BSA, the unusual square-four design found a home with Ariel and featured a pair of parallel twin blocks siamesed with their transversely-mounted cranks geared together and sharing a common head with overhead cams. This compact design allowed a four-cylinder powerplant to be fitted in to frames that were normally home to engines with one or two cylinders.

1952 Ariel Square Four L Rear

The original 500cc engine was eventually enlarged to 601cc’s to increase torque for riders who wanted to fit a sidecar to their machines, but the OHC design had a propensity for overheating the rear pair of cylinders, as cooling airflow was blocked by the front pair.

1952 Ariel Square Four R Front Engine

The engine was completely redesigned in 1937 with pushrod-operated overhead valves and a big displacement increase to 997cc’s. Aluminum replaced iron in the head and cylinders in 1949 for a significant savings in weight, and the final iteration of the engine introduced in 1953 was distinguished by four separate exhaust pipes exiting the head, although this example is the earlier, two-pipe version.

1952 Ariel Square Four Dash

From the original eBay listing: 1952 Ariel Square Four for Sale

An English country cruiser capable of 100mph….

Gaining popularity as “the poor man’s Vincent”, the Square 4 is steadily increasing in value.

The current owner is the fifth (first not named David) in a line that traces this 52 Ariel Square 4 Mk I’s origin to New Jersey; where it was purchased new in 1952.

The most recent previous owner bought the bike while on a trip in N.Y. State in 1996. After the purchase he had a full restoration performed prior to displaying in his collection.

Upon receiving the machine, the current owner kicked it over twice and it started right up and ran nicely. He rode it around his neighborhood for an hour, and then carefully decommissioned the Ariel for display in his collection.

The odometer shows 56,818 km or 35,305 miles.  The current owner has done a fair bit of detail work on the machine since acquiring it – much polishing, inspecting, cleaning and servicing inside external cases etc. He removed and cleaned the oil tank & lines and installed a rebuilt exchange oil pump from Dragonfly.

The frame is refinished but not powder coated and makes it look very authentic. The tins are all superb in that they are original but refinished beautifully and correctly. Chrome is all perfect.

All of the wiring was redone correctly and everything works. Even the tiny light in the speedo and the brake light. (all the lights work in other words)  The bike includes the original ignition key and the (optional?) jiffy side stand.

The owner is in possession of a dating certificate with an extract from the Ariel Works Ltd. despatch record books confirming that all of the major components on the machine are original. With the exception of perhaps the rims, tires, spokes and buddy pad this bike has all of its original pieces, nicely and carefully restored.

Also included in the sale are the original owner’s manual signed by the first two owners and a copy of the 1970 NY State vehicle registration bearing the name and signature of the second owner who purchased the bike from his friend and original owner in 1957.

1952 Ariel Square Four R Rear2

Weight was relatively low for such a complex machine and the bike could top 90mph, no small feat in 1950, although maximum performance wasn’t really the point, since lighter, simpler singles like the BSA Gold Star could match those numbers. It was the square four’s smoothness and sophistication no twin or single could possibly match that was the source of the bike’s lasting appeal, with production lasting from 1931 until 1959.

1952 Ariel Square Four L Tank

This example is in excellent condition and appears to be well-documented. Bidding is north of $22,000 with plenty of time left on the auction. The popularity of some bikes will naturally rise and fall with prevailing trends, but Square Fours have been steadily appreciating in value for some time now, and looking at this bike, it’s easy to see why.

-tad

1952 Ariel Square Four L Side

1956 Ariel Square Four for Sale

1956 Ariel Square Four R Front

Motorcyclists are often lone wolves, men and women of few words, rugged, independent folk for whom actions speak louder than words. Like the seller of this tasty classic Ariel Square Four.

From the original eBay listing: 1956 Ariel Square Four for Sale

1956 Ariel square 4 runs great, starts first kick. Everything on the bike works well. It does need front fork seals they are leaking a bit.

It comes with a clear Texas title. Please ask questions

That’s it, the whole listing. Luckily, the photographs are bright and clear and show a bike in very nice condition. I’d love to know a bit about this bike’s history, updates and maintenance that have been done. I guess the seller figures prospective buyers already know all about these. In case you don’t I’ll fill you in a bit.

Produced between 1931 and 1959, Ariel’s Square Four began as a 500cc machine and ultimately grew to the 997cc machine you see here. Weighing in at a relatively light 425 pounds and producing 45bhp it can easily keep up with modern traffic, although limited cornering clearance and period brakes mean you should plan your maneuvers well in advance. While it isn’t necessarily much faster than some of the bigger twins and singles of the period, the four was obviously smoother with a wider spread of power.

1956 Ariel Square Four R Rear

Keep in mind that four cylinder motors were considered very exotic until Honda and Kawasaki flooded the market with them in the early 1970’s. Twins and singles ruled the motorcycle world for the most part, and the square four was a way to introduce the smoothness and power of a four into existing frames originally designed to hold singles.

Like the square four two-stroke race replicas of the 1980’s, the Ariel is quite simply two parallel twins with their cranks geared together sharing a single head. Early bikes tended to overheat the rear cylinders, as you might expect, since they were blocked from receiving any cooling airflow. Later revisions to the bike addressed this, although it was always a weakness of the design.

1956 Ariel Square Four L Front

The later examples were known as “four pipe” bikes for obvious reasons: note the four separate exhaust pipes coming out of the head. In addition, the Mark II redesign featured extensive use of aluminum for the block and head, saving 30lbs over the earlier models.

The buy it now price is set at $21,000 which pretty big money. Ebay indicates several offers have been made, but I’d expect they were pretty far off the asking price, which seems a bit steep, even for a bike this nice.

-tad

1956 Ariel Square Four L Rear