FUBi designed as an road bike

Road bikes are built for speed, so are also racing bikes. But a foldable road bike and a foldable racing bike? Does this at all make any sense?

Well , it can make perfect sense to have road bike features on a full sized foldable bike like FUBi.

The interesting thing about road bikes are the solutions used in order to reduce resistance.  The very thing we all have to overcome when we crank the best we can to move forward on our bike.

It is therefore stupid to think that reducing resistance is not anything that is of interest to a normal bike user. On the contrary it is of vital importance for any bicyclist.

High or higher resistance reduces the speed, increases the effort and strain, reduces the radius of operation, makes it more difficult to go uphill, and most importantly it reduces the enjoy ability of the ride. In short we spend more time and effort going the distance.

The resistance in a bicycle consists basically of three different parts, bearing frictions (including drive train), tire rolling friction and aerodynamic drag. There is not anything else a constructor/designer can address because what would that be.

Aerodynamic drag is exponential, that is doubling the speed will quadruple the resistance. But basically aerodynamic drag is mainly from the rider and depending on his posture and so on and is what it is.

Rolling resistance again is probably one of the most underestimated and often ignored factors on a bicycle because reducing this will leave more power for overcoming air resistance and gradients.

In general terms, the total drag of a cyclist will consist of 80% tire rolling resistance and 20% wind resistance at 10 km/h or 6 mph. At 40 km/h or 25 mph the numbers will reverse, with total drag consisting of 80% wind resistance and 20% tire rolling resistance. Even at this high speed rolling resistance is one fifth of the total resistance. Negligible?  Certainly not.

And when it comes to bearings and the resistance from them, not even this vital part of the total resistance is negligible because it all adds up. You would be surprised of how sluggish a normal regular bicycle can become just form poorly maintained hub bearings. The hubs have to be properly adjusted and greased to function. But we most of the time do not even notice this significant decline in performance because it is so gradual.

folding fast road bike

Therefore FUBi is designed for speed and this mainly by using road wheels and tires and by using high quality low fiction maintenance free deep grove bearings in the wheels and elsewhere. This way you can use more of your energy fighting the wind and not the bicycle.  And high speed can always be translated into lower speed and less effort and therefore less sweat, a thing that can be of importance when for example commuting.

Ulf/ the FUBi man

by Ulf