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EROS, PETs and others

by Paul Hornby

An electric cyclemotor now on the American market is the EROS.

It is not named after the Greek god of love; the letters stand for Electronic Regenerative Operating System.  A small cylindrical 300W motor, weighing 3lb, is fitted between the saddle tube and the seat stays of the bicycle, which it drives by a friction roller onto the tyre.  The roller is driven directly by the motor without any intermediary gearing.  The unit is sold complete with a 13Ah sealed battery, a 30A relay, a " pressure speed control switch" for handlebar mounting, a battery charger and mounting brackets.  The battery and electronic gubbins are housed in a box fitted inside the frame diamond and clamped to the front down tube.

The motor is wired so that it can act as a regerative brake, rather like the motors on the late-lamented trolleybuses of my childhood.  Presumably the rider is able to manipulate the handlebar control to switch the motor to act as a brake, at the same time feeding the electricity so generated back into the battery.  As the leaflet says: "Amazingly, you can use your EROS indoors as an exercise generator and charge your batteries as you exercise" and, to this end, an optional indoor Power Stand is available for exercise bike use.  So, you exercise like mad indoors, and then have the motor to propel you on the road because you're too tired to pedal.  Other extras are a handlebar operated roller lifter, a battery condition indicator and what are described as "custom mounts".  No indication is given as to the manufacturer's name or the country of origin, but it is available from Five Flags Distributing, 7621 Pine Forest Road, Pensacola, Florida.

This firm is also marketing an electric bicycle known as the PET (Portable Electric Transport): a small-wheel Dahon folding bicycle with an electric motor driven roller (not an EROS) above the rear wheel.  It has a 12V 13Ah sealed battery, a maximum speed of 15mph, but a surprisingly low range of only 7 miles.  An optional extra is a solar battery panel and the whole thing is probably manufactured in Taiwan.  Five Flags are also marketing the MX5 petrol cyclemotor described by M W Doran in the December 1995 issue of Buzzing.

As amny readers are interested in other minimalist motorised transport, here are some currently avalable in the USA.  The Go-Ped, a skateboard-sized stand-up adult scooter with fold-down handlebar, 6&quote diameter × 2.5" wide wheels with solid tyres, drive to the rear wheel by a 22.5cc two-stroke engine developing 1.2hp @ 8,000rpm, a maximum speed of 20 and minimum of 2mph, and what is claimed to be a world record turning radiue of 30".  It is not clear from the leaflet how the rear wheel is driven by the engine, but it is available in two models, the top of the range having "unique ultra smooth hydraulic automatic transmission".

The Phantom Scooter is a larger version of the Go-Ped, from a different US maker, with a 25cc two-stroke engine, chain drive to the rear wheel with automatic clutch, 8" × 3.25" pneumatic tyres, fold-down handlebar stem and a maximum speed of 25mph, with a range of 30 miles on a tankful of petrol.  Three models are available with different 'trim' levels.  These stand-up motor scooters are following a tradition started with the Autoped in 1916, and seem to be a purely American phenomenon.  They seem to be quite popular over there too.  I have seen people weaving through the rush-hour traffic on them in New York City - no helmet, no licence plates - try getting away with that in London!

A number of motorised skateboards are also available, but one novel motor unit caught my eye - the Roller Cycle - a sort of autowheel for skateboarders and roller bladers.  A two-stroke engine powers a single wheel, which has a disc brake.  The frame stem connects to a tubular U-shaped member, the curved part of which is padded and fits in the small of your back, while the two ends curve to the front to form handlebars on which are mounted the throttle and brake controls.  It will push you at up to 25mph with a range of about 25 miles on a tankful of petroil.  Tandem tricyclists could use it as a true cyclemotor.

First published - 1997

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