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Wednesday, June 10, 2026

Fraser Ro-bike part 2

 

Tandem when it belonged to Matt

Relieved and slightly dizzy after having a go at the Pinata

Packing for the big trip

Whew, I got there

My friend Tony

Graham (riding Aki's bike) and Aki 

Twin rowbikes

Pinata. As the birthday I was required to have first  go at it, and hardly touched it with the stick.

Sunday morning fruit stall

Orange and Almond meal cake


"A bit volcanic", but I put sliced apple, jam and cream on the banana bread and it was well received.


Matt's Ro-bike. 


Hi

(This post continues on from here . )

A few weeks have passed since I first got the secondhand Fraser Ro-bike. Firstly, one of my contacts, Matt came through and sent me pictures (top and bottom) of the 2 Ro - bikes he once owned, one of them a sociable tandem trike of which I believe only 2 were made.

So as well as trampolines, Bill Fraser  made giraffe unicycles, recumbent bikes, and tandem and single Ro-bikes. I'm quite glad to unearthed a bit of Australian cycling history, and Matt's is the first picture of a Fraser tandem Ro-bike I've seen. 

After getting the Ro-bike on the road, I gradually started venturing out on it, including to a local Cafe where I go regularly on Sundays. I can get there via very quiet streets and bikepaths - on the way back I found a small Sunday fruit market which was new to me. I was a bit emboldened by successful rides, and decided to have a 66th birthday party, with a Ro-boke theme. I could take mine, and with a bit of luck Aki would come along with his too. As well I could have it at WeCycle, where a fair few of my friends hag out on a Saturday. 

Somehow it all came together! I cooked 2 cakes for the event, and was successful with a jam, cream and apple topping. Leaving home with 2 milkcrates worth of supplies on the back of the Ro-bike, I felt like a small kid running away from home with all my worldly possessions tied up in a plastic bag over my shoulder, ie, impossibly naive and doomed to failure. But somehow it worked, and thanks to my family and friends who came along. Completely unannounced, Marco (helped by Carlos and Mike) ran a Pinata - the last one I'd seen might have been 15 or so years ago - which added to the fun, and the Ro-bikes were well used and enjoyable too.

I copied text from and added some notes to the article mentioned in the last Ro - bike post, here it is:

The Row-Bike, one man's design for easy riding by Arthur Jones. 

They say that there is nothing new under the sun, and "they", whoever they are, are probably right. The idea of a bike which you propel by pulling with your arms at the same time as you push with your feet has been around for a long time. In fact, I have an idea that the principle is being used in those streamlined "future bikes" that are doing 100 km/h in America (Not true! The bikes mentioned are just streamlined pedal bikes). And those figures are not a figment of my imagination; a tandem recently achieved 101.25 km/h (see https://www.ihpva.org/hpvarecl.htm: 101.27km/h in the Vector Tandem designed by Al Voigtand ridden by Dave Grylls and Leigh Barczewski, May 4, 1980), and a single seater notched up a respectable 94.4 (see https://www.ihpva.org/hpvarecl.htm: 94.77km/h in the Vector single designed by Al Voigt and ridden by Dave Grylls on October 27 1980), so 100 km/h will no doubt be reached by a solo cyclist in the not too distant future (100km/h was first exceeded in 1998 by Sam Whittingham, and the current 200m flying start cycle record is 144.17 km/h set by Todd Reichert in Aerovelo in 2016)

However, the bike you see in the accompanying photograph is not intended to be a speedster. It is built for comfortable, easy, efficient riding to and from work, for rides in the country and for touring. It is the brain-child of Bill Fraser, of Mentone, Victoria, who not only designed it, but built it himself from scratch. His aim was partly to reduce man's dependency on motor cars and partly to assist the average Australian to be a healthier, fitter and happier person. All very laudable, you may be thinking, but why not ride an ordinary bike and achieve those aims? The answer is that there are several advantages in the arms-and-Iegs bike over the traditional ten-speed model. Firstly, you can obviously travel much further (or faster) for less effort, not just because you are using all four of your limbs to move you along, but because the lower seating position reduced wind resistance. The average cyclist, riding along at 20 km/h uses half of his total output of energy in overcoming wind resistance, and if the frontal area is reduced, either by adopting the racing cyclist's crouch or by sitting closer to the ground, there is a great saving of energy. Secondly, the nearer you are to the ground, the lower the centre of gravity, which helps stability, and it is much easier to put your foot to the ground at a traffic hold-up, which means less wobble. So, admitting the advantages, what is the bike like to ride? The answer is —perfectly easy — when you get, used to it. I had a go on it, but in spite of all my attempts, I was only able to freewheel for a metre or two, with Bill running frantically behind to steady me if I showed signs of falling off. I must admit, however, that the fault was all mine, because others who tried it were able to ride up the street, turn around and come back again with no trouble at all. As you can see, when Billis aboard it looks as easy as ... I can hardly say "falling off a log" can I? ... but you know what I mean. It is different from riding an ordinary bike, but no more so than riding a high-riser or a BMX bike, I should think. Bill was able to get up to a very highspeed in a short space of time, as the combined arm-pull and leg-thrust really makes the bike move. Acceleration is also made easier by a system of gearing that, to my knowledge, has never been used before on a bike. As you can see from the second photograph, there is a rocking arm attached to the standard head tube, and on it is a strip of metal with ratchets cut out of it — or teeth put on it, if you like. The chain is attached to this ratchet by a nylon cord and an "S"hook. Obviously, the further away from the pivoting point you place the hook, the further the chain (and therefore the bike) will move, and if you hook on to a ratchet near the pivot, the bike will only move a short distance. You thus have a "gear box" that is fiendishly simple in operation, and as Bill's bike has 16 notches, he has 16 gears to play with.

Just think of it! All those gears with no extra weight, no chain running out of line, no gritty cogs, no heavy hubs, and the selection of each gear only a matter of releasing the hook and moving it along to the next ratchet. I was unable to find what the equivalent gears were

on a normal ten-speed bike, but those with a knowledge of mechanics might be able to work something out from the following bits of information that I was able to pick up. The ratchets are approximately an inch apart, there are 14 teeth on the rear cog (the size of the chainwheel is, I think, irrelevant) and the back wheel is 24 inches in diameter.

The other point in the design that interested me was the steering. With the handlebars moving backwards and forwards all the time, it is obviously difficult to steer, but this problem was overcome by a system of linkages connecting the bars and the head stem.

These had to be carefully engineered, as too much side-to-side movement would foul the swinging arm. The movement is obviously very limited, but Bill assured me that it was no problem, and when you come to think of it, most steering on a bike is done by leaning it over to one side, and it is only when you have to turn in a tight circle at low speed that you have to turn the bars very much.

There are one or two other refinements, such as a padded seat and backrest, which can be moved along the top of the frame to accommodate the long and the short and the tall, without, as is the case on your bike and mine, affecting the distance from the seat to the ground. There is another advantage in the wheelbase, which is only 33 inches, some six or nine less than the ordinary bike, and this makes for more responsiveness — at the cost, it must be admitted, of a slightly more bumpy ride.

The frame itself is very simple—just two curved lengths of "U" section steel tubing, all of which helps to keep down the weight. Actually, the bike is fairly heavy, weighing in at 16.5 kilograms, but as Bill pointed out, this is something of a prototype (although he has sold a dozen of them).

At the moment, it is an all-steel bike, and probably weighs no more than its equivalent in ten-speed form, but considerable weight savings could be made by an extensive use of aluminium alloy. I would like to see a light-weight model made, with narrow section tyres and a light frame, because I think that it would really move. On the debit side, all "sit down" bikes suffer from the disadvantage that the body weight cannot be placed over the pedals, with the result that such bikes are very slow on hills. With Bill Fraser's bike, there is the added problem inherent in all "push-pull" bikes, and that is the fact that drive is not continuous. The bike moves along just like a rowingboat (in fact, it has been ch ristened 'The Row-Bike'), with a surge of speed as the pressure is applied, followed by a gliding motion as the "oars are feathered", as it were. This is not a disadvantage when going along a level stretch of road, and is, in fact, an advantage, as you can relax and enjoy the scenery as you freewheel between strokes, but on hills, it makes for hard going. It really means that you are continually slowing down and accelerating, and you will know how frustrating that is if you have ever been forced to brake when climbing a hill. That, to my mind, is the only disadvantage in a novel design that has many plus features not usually found in a one off design, and if you are interested, the address to write to (but not yet, as Bill is still riding his bike to Brisbane) is:

The Fraser Trampoline Company, 7 Aluena Street, Mentone, Victoria, 3194. Incidentally, if you are thinking of knocking up your own model, Bill has patents pending on the design.

 

 

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