Dahon is a US company and is the world’s largest manufacturer of folding bikes.
According to Dahon’s Joshua Hon, VAX – it stands for virtual axis – will make "non-suspended city and trekking bikes obsolete."
VAX is pivotless and, said Hon, is an "elegantly simple new technology." It is said to deliver lightweight, stiction-free suspension for frames, forks and other components.
To you and me they’re sheet springs on a single plane but to Dr. David Hon, Dahon president and holder of over 90 patents, VAX is "the most significant technology we have ever developed."
Hon said VAX is a completely new way to implement suspension.
"And not just for the bicycle industry, it is completely new to the engineering community," he claimed.
"We are now at work on a scientific paper to present this technology. We are incredibly excited because the applications for VAX technology extend well beyond the bicycle industry. But the fact that VAX suspension provides smooth, friction free suspension in one direction yet is torsionally stiff in all other directions, makes it very well suited to bicycles."
Engineer and journalist Brant Richards of On One saw the VAX pix on this website and belives the system has potential.
"Very simple. Clever. They’re similar to the flexures used to support things in wind tunnels. But I hope they’ve got their welding right or they’ll have fun with those."
Compared to existing suspension technology, VAX has a number of distinct advantages, said Hon:
"Friction is a traditional suspension system’s worst enemy. Friction prevents smooth functioning of a suspension system and will only increase as bushings and bearings wear out, lubrication dries up, and parts become contaminated with dirt. VAX technology delivers friction-free performance that is smoother than anything on the market," claimed Hon.
"Traditional suspension systems make use of bushings and bearings at the pivot points. These pivot points require regular lubrication and maintenance. The fit at these points must also be very precise. Inevitably, these pivot points wear and develop play. VAX, on the other hand, does not require any pivot points. Without pivots, bushings or bearings to wear out or lubricate, VAX suspension will operate at 100 percent capability for the life of the bicycle frame or fork."
"Weight is one of the biggest design obstacles for suspension frame and fork designers. Traditional suspension systems are heavy. VAX frames and forks can be built to be lighter than traditional supension systems because the suspension elements of the frame are also structural elements."
"Traditional suspension frames and forks are significantly more expensive than non-suspended frames and forks. Costs are driven up by the use of exotic materials to reduce weight, tight tolerances, increased complexity during assembly and painting, and the additional cost of pivot bearings and shock units. In contrast, VAX technology can be implemented for much lower costs when mass produced."
Dr Hon said VAX is best suited to bicycle suspension applications of less than 3 inches of travel.
"VAX can easily be scaled up for longer travel applications but weight will increase accordingly, negating the all important weight advantage. [We] will focus initially on suspension frame and fork designs for trekking, city, and folding bicycles," said Hon.
“VAX can be so simple, durable and cost-effective, there will no longer be a reason not to add suspension to these bikes. Ten years from now, we may look back and mark 2002 as the beginning of the end for non-suspended bikes.”
Sales of VAX-equipped Dahon folding bicycles will begin in May 2002. In 2003, Dahon will introduce traditional non-folding VAX bikes under the Dahon brand as well as for OEM customers. From 2004, Dahon will license the technology to other frame, fork and bicycle manufacturers.
Dahon will introduce VAX at the 2002 International Taipei Cycle Show in April.