Working on aerodynamics – part two

Here we are going to see the progress on the actual installation of the fairing.

I have divided the work on two steps:

  • the front part

  • and afterwards building of the rear part

Installation of the front part of the fairing

I have used here a Zotefoam sheet I already had in stock: it is with pretty low density of 33kg/m3

The advantage is that it is very easy to work with, and very light.

After the right shape is found, with a hot air gun it’s possible to warm it up so the shape is kept as desired.

Here it is one of the first attempts to lay down the zotefoam around the Windwrap fairing on the “nose” of the bike.

Special care to be given where the zotefoam is positioned around the front “nose” in order not to create any unwanted lack of continuity.

This is just to find the best shape to be given, som quite a few more attempts have been necessary.

front nose windwrap

Here I have already started to give the right shape where the shoes are positioned on top of the crancks.

This is typically where the profile must be  modified to avoid interference with the top of the shoes.

To verify that there is no interference the best way is to clipse the shoe and then turn the pedals (as here on the right).

The aluminium bar is to ensure that the profile is as much as possible horizontal.

Front nose

Here it is the side view where I have already cut few cm of zotefoam for being able to get in and out from the bike.

Unfortunately the initial idea to cover also my knees is currently not feasible.

The reason is that the crank is positioned too high to let the legs pass below the fairing and still being able to see in front.

In order to lower the crank I would have had to modify the aluminium boom.

Unfortunately I had a lot of difficulties to find a local company able to solder aluminium, so I have decided to keep the original front boom.

In this way the front fairing will only reach my knees but will not cover them toward the handlebar.

side view

Here are some pictures of the completion of the front part of the fairing

  • front nose
    front nose
  • Front nose 2
    Front nose 2
  • from back right
    from back right
  • from back
  • Back TOP

Building of the rear part of the fairing

After having completed the front part it was time to work on the rear part of the fairing.

I finally received the new Zotefoam I ordered 2 months before (!).

The reason was that the combination of RED color and 45kg/m3 was a ‘non standard product.

Therefore the lead time was much longer…


A prerequisite for this was the finalization of the bottom part of the bike.

Here we can see that I have added a carbon plate:

  • 1 meter long
  • 30cm wide
We can also see the large battery (52V x 28Ah) which perfectly fits the area below the frame and above the carbon plate.

In this picture we can appreciate the size of the volume I have been able to create below the frame.

This is expected to help in two areas:

  • support for the lower part of the fairing

  • additional space for bags and various little objects below the seat in a very handy place

This is the bike with completed structure for the rear fairing.

Now we are ready to start the process to add the new Zotefoam sheets on the back.

Note that also the front motor has been installed (RH212 Direct Drive)

bike is ready to install rear fairing

First we start adding the Zotefoam sheet, size is:

  • 1 m high
  • 2 m long
It is important to use the heat gun to help the zotefoam sheet to take the ideal shape.
first side zotefoam

The Zotefoam here is thicker than the one used for the fron part of the fairing.

This means that it’s harder to give the expected shape and it takes longer to perform the activity.

On the other hand the final result is better and once in place with the right form it is more consistent and relatively rigid.

In order to keep the Zotefoam sheet very tight against the aluminium frame I have used ‘Dual Lock Self Adhesive Fastener Tape’.

Here the first right side of the rear fairing is almost complete.

The shape is perfectly following the support structure.

The hardest part was to go around the two small arches on top of the wheel, given the relative rigidity of this material.

first side complete

After I finished the first part on the right side of the bike, I had the opportunity to make some quick tests.

Here we are ready to leave for few kms ride with Alain with two Low Racers:

  • one without any assistance, with Tilting V2 installed 

  • the other one complete with electric assistance, V2 Tilting kit and partial fairing.

first tests

After having added also the left part of the rear fairing, here is the final result!

Now the bike is ready to start doing some preliminary testing.

Unfortunately we are now in complete “lock down” for the corona virus and using a bicycle here in France is not permitted.

Therefore no testing is going to be possible for several weeks….

  • completed rear fairing 1
    completed rear fairing 1
  • completed rear fairing 2
    completed rear fairing 2
  • completed rear fairing feet on
    completed rear fairing feet on
  • rear fairing back
  • front

This Post Has 2 Comments

  1. daniele g

    Hello Ruedi, thanks for your interest on my projects! I am going to reply to you in detail directly by mail….Kind regards, Daniele

  2. Ruedi Anneler

    good evening, Daniele,

    your solution is one of the best for a tilting trike I’ve seen so far. Do you sell kits or drawings to change a raptobike / raptobike low racer to a tilting trike? And what’s the content, the delivery time and the price? Could you please let me know?
    Thank you, all the best, and kind regarrds

    p.s. In case of interest I probably could support you with your fairing design, construction and build.

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