The first three Chromoly prototypes were made here in Oz where the steering geometry was perfected. The forth prototype was made in aluminium alloy in Taiwan and was shown at the 2006 Interbike show where it attracted a great deal of attention from dealers. It had a round section main tube that through testing was found to be not strong enough. We also found that if the adjustment clamps were not tight enough the front section could twist causing the trike to collapse! So we had new rectangular section tubing designed and made especially for the trike. This is stronger weight for weight than the round tubing in bending and keeps the front and rear sections in perfect alignment at all times including when the machine is being adjusted for leg length. It also blends perfectly into head tube giving a neat and clean appearance.
When the 2nd aluminium prototype (#5) arrived with the rectangular section tubing, I was quite shocked when I rode it. Being a higher trike, with a more upright seating position than the GT3, I had expected it be slower, harder to pedal and quite unstable. However, it seemed to be just as quick as my GTS!! It was also far more stable than I had expected! In fact I quite liked it! I can only put the difference between it and the earlier prototypes down to the extra stiffness of the rectangular section main tube. It could also be that using the differential to drive the two wheels instead of one rear wheel, as on our other trikes and most deltas, is more efficient, in the same way as Audi discovered that their 4WD cars were more fuel efficient than their 2WD cars. This was due to the fact that less stress is going through the driving tyres. In the case of the deltas, there could be an extra bonus with the differential, as with only one wheel drive, the drive would be offset by over a foot, and this would have to be counteracted by the steering, giving a certain amount of continuous scrub, when under drive. Thus the differential should make it easier to ride, and give less tyre wear.
However, we were not happy with the chain routing, and found ten aspects of the trike that we could improve. This included a boss in the rear of the frame for towing trailers or other trikes to make an articulated tandem. Some of the improvements were the fitting of a rigid and removable rear derailleur hanger, fitting of fender/mudguard mounts to the front fork, a more rigid seat mounting and a positive lock-stop for the steering. The brake calipers were also repositioned under the axle to provide protection for the discs when the wheels are removed and to provide space to mount the optional rear fenders/mudguards on top of the axle.
Late in March I arrived in Taiwan for the Taipei Bike Show and found the 3rd prototype (#6) waiting for me with all the improvements we had requested. After the show I rode the trike at the factory. Then I went over it with a fine tooth comb with the factory owner and a number of his staff. We found a further ten items which could be improved including using the Schlumpf Speed Drive to improve the ground clearance and using clamps on the seat stays to make seat angle adjustment easier and faster. However much time we spend working on new prototypes, it is only possible to go so far, as our customers are bound to use them in ways we could never even dream about. So we have now approved the Anura, as the new delta is called, for production and the 1st batch of 120 should be finished by the end of June. Having consulted widely with dealers, customers and a special focus group about the Anura, as it was being developed, we are now confident that this trike will set new standards for delta trikes worldwide and be an outstanding addition to the Greenspeed range. So if you have any interest in this type of trike, I suggest you contact your Greenspeed Dealer in July to arrange a test ride. Deliveries should start in August.
History as told by Ian Sims, CEO, Greenspeed Pty Ltd.