Hambini vs Flo Cycling

I do not usually write this type of post but I wanted to clear a few things up. I am an engineer by training and one of my weaknesses is I am unable to articulate myself as well as I would like. This is mainly because English is not my native language. There have been a lot of negative words exchanged between myself and FLO cycling about their wheels and I wanted to clear a few things up.

My engineering is Genuine

A key fact that seems to have been glossed over is when a set of FLO wheels was originally tested, the results were kept private and I went to lengths to contact FLO cycling to inform them that their wheels had performed badly. I waited a number of weeks and received no reply. I took the view that as a comparative nobody in the cycling industry they did not really care. So I proceeded to publish the results on my blog.

At this point FLO got interested – they did not want the negative publicity and asked me if I was using the same tyres for all wheel tests. A bizarre question but nonetheless I answered.

As this saga progressed…

Myself and my colleagues who are all engineers became subject to somewhat aggressive questioning complete with racism and the answers provided were not deemed to be satisfactory. The line of questioning was down a steady state test path when the test carried out was in transient state. The main point which stands firm to this day is that FLO cycling and others test in a steady state condition with what is colloquially called Utopian airflow.

Wheels are ridden in conditions which are much more chaotic and random. In random and chaotic (turbulent) conditions, the effectiveness of aerodynamic shapes diminishes and you can experience this first hand when flying on an aircraft as it goes through turbulence – the wings lose lift. Testing in a steady state will give a power absorbed but it is 100% not indicative of the real world.

The understanding of unsteady airflow in the aerospace industry is a specialist subject, understanding of it in the cycling industry is almost zero and the majority of aggressors are essentially ignorant of it despite all of the visual clues that point to transient turbulent unsteady flow.

As the situation with FLO progressed. A letter was received by my employer from a firm of solicitors representing FLO cycling. FLO have strenuously denied they sent this letter but neither myself or my colleagues are convinced for the following reasons:

  • This letter was sent to a company address in the wrong country. Post to receiving this letter, a member of the Slowtwitch forum called Dan Empfield sent me an email asking where I worked and eluded to the incorrect said country. I did not respond. Days before, a letter was received at the address in the wrong country. Pure Coincidence – unlikely?
  • I made a statement in my blog; “The FLO cycling and Hunt wheels performed badly, they appear to have been designed by individuals with a limited understanding of aerodynamics of rotating objects”. It is difficult to prove correct methods in aerodynamics as there are few recognized codes of practice. Hence, I elected to cite their use of bearing engineering (tribology) as a basis for the statement. I included written responses from SKF, FAG and NTN. This was sent to their solicitors The page in question was deleted from the FLO website shortly afterwards. I thought this may happen so I took a copy of it, which you can view HERE. Coincidence once again? – Unlikely.
  • Flo have been called out on multiple occasions for using CFD as a marketing tool. They neglected to nipples or even the spokes in their models! To date, they have not responded

What is in it for me and my colleagues

The answer to this question is nothing. All testing is done for free and performs part of a training programme for young engineers. Where a manufacturer requests a test, then we do this for free and ask they make a donation to a charity of their choice – usually the Red Cross. Despite what you may read on various internet forums.

The situation in the bicycle wheel industry is smoke and mirrors gone mad. A product is being sold on misinformation that the end user has no way of verifying. Added to this, there are various individuals who are actually wheel company employees sticking up for their testing methods because they know they are fundamentally flawed.

And finally…

Before purchasing a set of wheels, the question that you need to ask of the manufacturer is:

Please explain to me how your test method is indicative of real world turbulence.

Leave a Reply