A highly original and unrestored example of the earlier and rarer “upright cylinder” version
A thoroughly useable example having covered the Banbury Run on a number of occasions
Complete with a fascinating paperwork trail and archive
The Appeal
It is surely the rarity value of the Calthorpe Ivory that sets it apart. Calthorpe was a Birmingham based motorcycle manufacturer that had evolved from both bicycle and early car production. By the mid 1920’s, however, they had carved a niche in motorcycle production and even introduced their own proprietary 350cc engine in 1925.
In 1929, the year of this example, the Ivory was launched as a range topping sports model with a “domed racing piston” and a twin port head. The upright engine configuration of this model was produced just for 1929 with a “sloper” engine being introduced for 1930. That can only add to the rarity value of this charming example.
The riding environment of the Calthorpe Ivory is in charming, original condition throughout
Providing a low and comfortable riding position with a saddle height of around 26 inches
Controlled by a period-correct hand throttle and tank mounted, hand gear-selector
By today’s standards the Calthorpe Ivory is a diminutive motorcycle rendering it pleasingly manageable and suitable for riders of all statures and builds. Seating is courtesy of a saddle type perch with a double spring mounting to help absorb the bumps. A non-standard oblong pillion seat was removed by the current owner in the name of originality, but the mounting holes are still present in the mudguard.
The rider’s eye will immediately fall on the single piece of instrumentation which is the original ammeter set into the rear of the black headlamp bowl. An original Bakelite Lucas ignition switch is fitted to the top of the lamp.
Numerous hand controls are affixed to the upright handlebars including the hand throttle which apparently, once mastered, is a real boon to smooth progress. A button operates the original Bosch horn and makes a delightfully quirky noise. The handlebar rubbers appear to be original and are in a good used condition.
An impressive knurled steering damper knob sits at the centre of the bars and is deeply engraved with the sweeping “Calthorpe” name. The overall impression given is one of compete originality giving a fascinating insight into a bygone age of motorcycling.Pcn3kIroEeRSEBMqdD7DAaDPKGsqmuDZV3yZKm9v.jpeg534.4 KB
The Exterior
The Calthorpe Ivory was named for its original off-white colour
Some of this original paint is retained together with later painted red wheels
This non-restored example provides a fascinating insight into its history
To our eyes this unrestored 93-year-old motorcycle is all the better for that. In its fundamental originality lays a large part of its charm. The visible repairs and mixes of paintwork and heavily patinaed tank lend an almost archaeological dimension to the motorcycle’s history.
Elements of the mudguards and oil tank retain the eponymous Ivory hues. The spoked wheels have at some point been painted red with the frame and structure of the machine being finished in black. None of the paintwork is pristine but it all helps tell the story of this aged machine.
The teardrop petrol tank is finished in chrome which exhibits heavy surface corrosion in places but does not affect the integrity or structure of the tank. The original rubber knee pads are inscribed with the Calthorpe name, and the hand operated gear selector is cleverly integrated into the offside knee pad. The nearside of the tank exhibits the “ghost” of the Calthorpe logo where the paint, now long gone, has protected the chrome below from the surface deterioration. A fascinating feature.
This Calthorpe Ivory is fitted with Calthorpe’s own 348cc single cylinder “Super Sports” engine
Originally rated at 3.5hp and boasting enclosed overhead valve gear
This example is the rarer upright cylinder model which was only produced in 1929
The current owner, previous owners, period and more recent road tests all attest to the sporty nature of the Calthorpe Ivory. It is a light machine by any comparison, with the original literature estimating the weight at around 320lbs or around 145kgs. This not only helps explain the sprightly demeanour of the Ivory but also its reported agility and lightness of the controls.
At launch it would be usual for a Calthorpe Ivory owner to maintain and repair his or her own steed and this is likely what most of the owners have done. The mechanical simplicity of machines of this period certainly made that much easier and quite acceptable. What we do know is that this example is regularly used and enjoyed and, pre-covid 2018, completed the annual Banbury Run with no issues or concerns.
There are a couple of known mechanical replacements which are alluded to in the letter provided by a previous owner. During his stewardship he replaced the exhausts with the fishtail examples now fitted which he fashioned from AJS parts. He also replaced the original Burman gearbox with another Burman three speed box from another model.
If you ask even an informed audience who has heard of a Calthorpe Ivory, you will start to grasp the true rarity value of this unmolested example. To our eyes, and those of the current owner, the unrestored condition of this machine defines a big part of its appeal, personality and value.
It gives the new lucky owner a number of options. It can be left exactly as it is and used and enjoyed as the current owner has. It could be restored to its original factory condition should that route be favoured. Or various waypoints in between may be favoured by the new owner. Whatever the future holds for this Calthorpe we are confident it will continue to bring pleasure and enjoyment in spades.
