Imitation is the sincerest form of flattery
April 22, 2022 – Almere – Netherlands
If people ask us what’s the big difference in the Kú TF1 that will make them significantly faster compared to their current bike, we first direct them to the most obvious difference to all other triathlon bike designs. Our patented ‘FAST’ fork (Fork Air Stream Technology) which was based on the same development philosophies Richard McAinsh used in Formula 1.
When pictures of a new fork development by Cadex for the Giant Trinity emerged on social media in April 2022 we immediately started receiving calls asking if the Kú ‘FAST’ patent was under any threat. Giant seem to have adopted a design with wide fork legs stretching high either side of the head tube to under the rider’s forearms.
The questions we are being asked of the new Giant are not unfamiliar to us here at Kú Cycle, and we take each one as a compliment as true innovation will naturally attract imitators! Just prior the 2021 Tokyo Olympics we were fielding similar calls from the media looking for stories about the Lotus Hope track bike ridden by British Cycling. Many people had noticed this also had features, and not just the wide fork, that clearly appeared first in the Kú ‘FAST’ patent first filed in 2016:
Those familiar with the legal nuances of patents and protecting IP will know how difficult it is to prove infringement and in this new case we can probably say that Giant should not be expecting to hear from our lawyers just yet. Indeed, they may have more of a problem when the notoriously litigious Specialized see it. The Giant design seems to very closely copy the concept of the now discontinued Shiv.
The Shiv first made an appearance in 2018, two years after the ‘FAST’ Patent was filed and while development of the Kú TF1 was still very much under wraps. Based on the Shiv and the Hope Lotus it is hard to see from the limited pictures currently available what new ground, if any, the Giant fork design is breaking. Opinions were always divided on whether the Shiv was a great breakthrough in aerodynamics, and this may ultimately have helped lead to its early demise. The Hope Lotus performance at the Olympics was, at best, unspectacular.
What innovation is enshrined in the ‘FAST’ patent that Giant, with Hope and Specialized before them, have missed? In simple terms none of these alternative designs fully address the critical issue for aerodynamic performance at the front of the bike. That issue is very simply the blockage experienced by the air when it first meets the bike trying to cut through it.
By eliminating the head tube and steerer of a conventional fork to frame interface the Kú TF1 takes this part of the bike, we call it the Kú Steerer Pivot Box (SPB) and repositions it between the rider’s arms. In turn this allows the wide fork legs to extend high above the front wheel leaving a largely unobstructed path for the air to negotiate. Careful sculpting of the duct thus created allows for control of the air as it continues its journey passing downstream and around the rider.
REDUCING AIRFLOW BLOCKAGE ON THE FRONT OF THE BIKE
LOWERING OVERALL BIKE
+ RIDER DRAG
IMPROVING DOWNSTREAM AIRFLOW CONTROL
The new Giant, just like the Shiv and Hope Lotus before it, does not address the fundamental issue of blockage at the front of the bike that is common to all designs that leave the frame hugging the top of the front tire.
DOES THE FAST FORK WORK?
The Kú TF1 was developed to beat the market gold standard for triathlon bike aerodynamic performance for the past 15 years, the Cervelo P5. Early Computational Fluid Dynamic (CFD) analysis was based on developing the high and wide fork using scanned models of a rider on a Cervelo P5 to investigate the baseline case for the high fork concept.
Those early CFD results clearly showed the advantage and potential for development of the ‘FAST’ fork concept to improve the aerodynamics of the bike + rider system. Five years after the original CFD proof of concept study, and just a month ago in some unseasonal early March 2022 sunshine, we had the chance to test this core concept of the TF1 in the real world.
In back-to-back aero performance testing over four days both outdoors and in the velodrome the Kú TF1 demonstrated a 6% improvement in CdA over the 2021 Cervelo P5 disc.
The Cervelo P5 test is just one of a great number of bike-to-bike comparisons pitting the Kú TF1 against a range of competing brands in over 1000 data collection kilometres of rider tests that Kú Cycle have conducted across 5 Kú aero performance camps over the past 6 months.
REAL-WORLD AERO PERFORMANCE RESULTS
Interestingly the Kú TF1 has not been in a wind tunnel where the significance of the high fork would not necessarily show up so emphatically. The real benefit of the ‘FAST’ fork is showing itself when tested in the instability of real-world aerodynamic conditions, or in simpler terms, race conditions!
No doubt that in due course we will hear how well the Giant tested in the wind tunnel. What we, and those athletes fortunate enough to have experienced the TF1, do know from our testing is that the Kú TF1 is consistently outperforming designs seemingly developed with good wind tunnel numbers in mind.
The full story behind all these aero tests and actual results will be posted on our website over the next few months. So hereby a little sneak preview of the March 2022 CdA test results of the Cervelo P5 versus the Kú TF1 comparison.
Right now we will accept that imitation is the sincerest form of flattery, and at Kú Cycle we look forward to the opportunity to have a head-to-head comparison…
Media Contact Kú Cycle:
+31 (0) 683 033 920
About Kú Cycle
A Dutch based company with a mission to design bikes and performance solutions that will change the sport forever – the perfect fit between body and machine. We believe a rider’s position should be established independent of the bike and will therefore reposition bike fitting services from a post-purchase service to a pre-purchase service. A new production process (built-to-order) and a completely different sales model are introduced with a single objective: athlete performance delivered!