This article is taken from the TA Gazette, Christmas 1986 issue and provides an insight into the development of the double freewheel unit as a cheaper alternative to the differential and also the reasoning behind George Longstaff’s axle design. At the end of the article we also get an insight into the way some of our members reacted to Georges innovation. I think it fair to say that he had the last laugh. Over twenty years later his two wheel drive tricycles are still being manufactured and many of his early machines are still giving their owners a smooth and trouble free ride.
“ANOTHER PEAK IN TRICYCLING HISTORY
by Stan Bray and George Longstaff
Continuing our series about Peaks in Tricycling History – HIGGINS DIFFERENTIAL – the Everest; ABINGDON AXLES – the Annapurna: like the mountain K2 it has been there all the time from the earliest days, as members old enough to ride a JAMES tricycle will know, but its high qualities have been taken for granted until recent years have seen it reappraised. TWO WHEEL DRIVE TRICYCLES Twenty six years ago, when I acquired my first tricycle in the form of a Holdsworth conversion set and a Coventry Eagle bike frame, it started a long and slow progression of curing one problem after another. A problem solving progression that I can guarantee many members have followed.
During my apprenticeship years I solved a lot of my trike problems by making superior components to replace those that were becoming difficult to obtain.
Ten years ago I decided that the trike frame that I had was very inferior to the equipment that was on it, so I decided to build a new one that would compete on standard and quality with the modern bike frames and equipment that were available.
I decided to re-design my axle unit with the intentions of removing all the niggling little problems that you come across on your trike frames.
Most trike riders will recognize these, with no doubt more that they can add to, such as:
a) Cup and cone bearings that will forever keep knocking
b) Cup and cone bearings that cannot be adjusted without a tight or slack spot.
c) Hubs that need a hammer and chisel to get them off, and once off will not run true when replaced.
d) Steel hubs that go black with rust, no matter how much grease you put on them.
e) Drive bosses that run so eccentric they hypnotise following riders.
f) Journal bearings that need a 100 ton hydraulic press to remove, and when done, half a dozen assorted spacing washers fall out.
g) Drive shafts that bend on the sight of a pot hole.
h) Axle loops that will only accommodate a 20 tooth sprocket.
No doubt many members can carry on the list. As I had ambitions of eventually making a living out of the manufacture of tricycles, I decided to investigate the possibility of an alternative to a one wheel drive. I already possessed a one wheel drive trike, a Higgins with a differential, and an old James double freewheel axle that I had incorporated into a winter’s trike.
I looked into the possibility of incorporating the double spragg and Torrington type roller clutches that were available through mainly agricultural machine manufacturers, but these all had some problems attached to them to put me off incorporating them into a tricycle axle.
The very high quality ordnance differential that Higgins modified for his trike axle was re-drawn. Quotations were then had from the many high quality gear specialists in the Stoke on Trent area, and ten years ago the best quote received was £75 each, with a minimum quantity of 150 units. (The same drawing re-submitted earlier this year for quotes was £ 170 each for a minimum of 100 units.)
As the price of a differential was completely out of the question, due to the capital needed for the initial purchase, and the fact that it would probably take at least three years to use them. Also, the average cyclists are not prepared to spend a lot of money on a trike (the last time some members spent money on their cycles was when they had their hobby horses re-shod).
With the differential definitely out of the question, I looked at ways of incorporating two modern freewheel units into one, to give a more economical alternative. I examined the many freewheel blocks to find one that would lend itself best to be incorporated into a double freewheel unit. The choice was the Maillard freewheel unit that came in two models, the course and the 700 compact, each having common largest sprocket locations.
The adaptor coupling would locate in place of the top sprocket, 5 or 6 speed set up could be used with only a small limitation on the sprocket size being caused by the loss of one of the two largest sprocket locations.
The axle unit was now designed to minimise most of the problems in the standard type axles, ie
a) Journal bearings were used that could be either fully sealed, semi-sealed or shielded to suit the customer needs, and can easily be removed or replaced.
b) Alloy hubs that easily locate on the drive shafts and stay concentric, easily removable with the help of a standard crank remover if they decide to become stubborn.
c) Drive shafts that have an increased bearing location diameter of 15 mm, against the 12.5mm 1/2” diameter of conventional drive shafts. The internal diameter of the drive shafts between bearing locations, reduced to 12.5 mm to save weight and to act as a safety factor if the shaft should fail due to overloading. (The shaft would fail inboard of the axle if overloaded and would only cause a loss of drive, the wheel would stay on, saving the rider from possible injury.)
d) The drive boss is located on a spigot which gives it a very accurate location, thus eliminating block wobble.
e) Axle loops that can incorporate 32 tooth sprockets and a gear hanger that is positioned in the same place as that on a bicycle fork end, thus giving superior gear changing.
The advantage of this type of axle is that all wearing parts, ie bearings and blocks can be easily purchased from either your local bearing stockist or your local cycle shop, leaving you dependent on the manufacturer only in the case of replacement parts in the event of accident damage, as the non-wearing parts should last as long as the tricycle frame.
The disadvantage of this type of axle is that it takes special tools to split the freewheel adaptor to replace the freewheels, though the freewheel body will take at least two sets of sprockets before they need to be replaced.
I would advise owners to remove the complete unit and send it to me for a service exchange, which will only cost the price of a freewheel block and body, plus postage.
The manufacture of the axle unit causes problems due to the fact that the four bearing housings have to be in line to +/- .001 ” , which cannot be achieved by direct brazing, due to the distortion of the metal. The accuracy is achieved by first machining the bearing locations before the axle is brazed to the frame, and then in-line finish reaming the four bearing housings in situ. This adds up to a very smooth running, efficient axle assembly.
Ever since I began manufacturing this type of axle unit, there has been a lot of comment on it in the TA Gazette and certain monthly magazines. I myself have winced at some of the comments, theories and statements that have been put forward, with only my sense of humour and shortage of time preventing me from putting pen to paper, but I would now like to point out that all those who have been involved in the double freewheel controversy are not, to my knowledge owners of such machines. It seems that the 250-odd owners of double freewheel axles are happy enough and far too busy riding them to get involved into such a ‘debate’.
As some members try to insinuate that tricycle manufacturers are only in it for the money, I would like to quote my late wife, who stated that, ‘Only idiots or tricycle enthusiasts would try to make a living out of the manufacture of tricycles’.
This comment can be backed by many enterprises which have tried and failed to make a business out of such a machine, therefore if it isn’t the manufacturer of the machine that gets the better of you, then it is their owners.
Constructive criticism and debate is very healthy for a product or design, but not at the expense of giving the impression that we have an association who need three wheels to keep their heads level!”
Both Stan Bray and George Longstaff are no longer with us, but George’s design lives on and can still be bought from:-
Longstaff Cycles Limited
Albert Street, Chesterton, Newcastle, Staffordshire.
We met Zonk Hastings, erstwhile member of the successful London East Trike Team at the 2014 Mildenhall Rally who is now working at Longstaff’s, especially on tricycles. He tells me that Longstaff are still building tricycles, both custom builds and their more commercial Cyclon trikes which are axles added to an existing bicycle frame.
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