Projects/Scooter Roof: Difference between revisions

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The main considerations in choosing a design for the windscreen were
The main considerations in choosing a design for the windscreen were


Optical clarity
* Size
Stiffness
 
Scratch resistance
The windscreen needed to be large enough to provide adequate protection from wind and rain. The windscreen also needs to be thick enough to provide sufficient rigidity. The main consideration here is either to have a windscreen material which can provide enough stiffness itself, or have a thinner, lighter screen which needs a frame to support it.
 
* Material
 
The main choice here is either to use glass, persepex or polycarbonate. While glass provides excellent scratch resistance it is very difficult to form in a one-off situation, it would be very heavy, and a laminated screen would be essential for safety reasons. The choice then comes down either to Perspex or Polycarbonate. Perspex is
 
* Stiffness
* Scratch resistance
* UV resistance
 
I again had a stroke of luck that I was able to acquire a second-hand comfort windscreen in good condition. I based my design on the use of that windscreen.

Revision as of 09:51, 12 December 2015

Background

I have been riding motorcycles for about 30 years and over the past 5 years have been commuting into work in central London on a daily basis, originally I used my Honda VFR750.

It became quickly apparent to me that the motorcycles are not best suited for city commuting and scooters are a better option for a number of reasons.

  • No need to continually chnage gears (the VFR clutch is very heavy!)
  • Far better weather protection
  • The ability to use an apron reducing the requirement for trouser protection
  • Small scooter engines warm up more quickly and don't use as much petrol
  • More upright, comfortable riding position allowing easier rear visibility

In addition to moving to a scooter for transportation I was also interested in increasing the amount of weather protection available which would reduce the amount of wet weather gear required for rainy/cold weather and so reviewed the various options.

Existing roofed and windscreened scooters

Honda Gyro Canopy

Honda have been selling these tilting 3 wheel scooters for many years in Japan. While I would be very keen to try one of these, there are very few in England and the logistics of importing one from Japan and maintaining it with poor availability of spares made me wary of continuing with this avenue. They only have 50cc engines so performance would be pretty poor too.

XingYue XY150

I bought one of these Chinese clones of the Honda Gyro, but found the build quality and road holding of these machines to be disappointing and decided to sell it again.

BMW C1

Many people use these roofed scooters, which were only sold for a couple of years around 2000. The concept is that the rider sits in a safety cell, held in place with safety belts. In many countries riders are not required to wear crash helmets while riding C1s but this exemption is not available in the UK. I haven't tried a C1, but they have a reputation for being top heavy, which is probably due to the weight of the glass windscreen and strong roof. Given that I will be doing a lot of traffic filtering this put me off a bit.

Benelli Adiva 150

These Italian machines are rare in England. They are convertibles with a retractable roof. With optional clear side fairings surrounding the windscreen they provide fantastic weather protection, and the plastic windscreen is much lighter than the BMW C1's glass equivalent. The Adiva also has a lot of storage space in the rear luggage compartment. I own a Benelli Adiva which I enjoy riding, but there are some disadvantages.

  • The 150 engine only allows speeds up to around 50 mph.
  • A two wheeled configuration in a relatively light scooter (135kg) means that the Adiva is susceptible to cross winds at speeds.
  • The tall narrow profile of the Adiva means that it is highly susceptible to being knocked over, and I have found my Adiva on the ground on many occaisions, which is a real problem when you are parking in London motorcycle bays.

Adiva AD200/250

These updates on the Adiva concept were produced from 2007 and answered went a long way to answering the lack of power of the original 150 Benelli version. The AD200/250 have never been sold in the UK so once again, while I considered buying one in Italy where they are more common, the cost and logistics of bringing one back to England did not appeal.

Adiva AD3

A relatively recent addition to the family of roofed scooters the AD3 helped improve the cross-wind stability of the original 2-wheel Adivas. Unfortunately they are expensive and once again not available in England. I would be very interested in riding one of these machines as they tick almost all the boxes for power, stability and weather protection.

So while relatively pleased with my Benelli Adiva which I used for a number of years it occured to me that perhaps the ultimate solution would be to place a roof on a Gilera Fuoco 500. The three wheel configuration and 250kg weight would provide the cross-wind stability, while the lack of plastic covering compared to other scooters would allow for mounting points.

Piaggio MP3 with Comfort Windscreen

This effort to increase weather protection is interesting, using a very large screen but without providing protection right over your head, and relying on a front-only mounting system. I have never tried an MP3 with this type of windscreen but I suspect that a lack of wiper will make visibility pretty poor when it rains, and the front-only mounting system will mean that there is a lot of whip at the top of the windscreen on uneven roads.



Designing the roof

After considering the options on the market I found that that none covered all my requirements. Round this time I had the opportunity to buy a second-hand 2007 Gilera Fuoco at a reasonable price. To me this was just about the perfect base for a roof project.

  • A proven 3 wheel tilting system for stability
  • Limited plastic coverings allowing for easy attaching of the roof to existing mounting points front and rear,
  • The ability to lock the suspension in the upright position when stationary at traffic lights, making it easy to hold the bike upright in windy conditions.
  • A heavyweight motorcycle which isn't going to be blown around
  • A reasonable power/weight ratio

From the start I was keen to weld the frame and avoid bolted connections, any bolted connections would increase the risk of excessive rattling and squeaking over rough roads. While it would be easier to weld a steel frame using MIG techniques, the frame would require painting before use. The requirement to paint the frame before regular use would mean that further welding would be very difficult without having to remove the paint, an ardous process. I also assumed that weight could also be an issue, but have never attempted to estimate weight for a steel version of the roof frame.

I therefore decided to use aluminium for the frame, the advantages of aluminium is both that it is light and naturally corrosion resistant. This meant that I had to develop my aluminium welding skills, a process which took several months before I felt confident enough that I could attempt the frame itself.

I chose a think-walled 1" aluminium tube for the main frame tubing. The advantage of the thick wall is that it reduces flex, but this comes at a price of reduced malleability, a problem which I'll come back to.

Mounting points

I was lucky to pick up a second hand windscreen and mounting frame for the fuoco, which allowed me to copy and weld up a new mounting block with the correct screw mounting positions and angles which would fit into the existing screw holes in front of the Fuoco steering gear. I was unsure if these mounting points would be strong enough to hold the roof stable against lateral force such as cornering and wind gusts and had it in the back of my mind that I would also need to extend the mounting points to bolt down to further screw holes which are normally used to mount the covers for the dashboard.

For the rear mounting points I could simply use the existing mounting points available for a rear pannier. Given that these mounting points were designed to carry around 20+ kilos of pannier and luggage, I was pretty confident that the mounting points would be strong and stiff enough to hold the roof stiff enough.

Windscreen

The main considerations in choosing a design for the windscreen were

  • Size

The windscreen needed to be large enough to provide adequate protection from wind and rain. The windscreen also needs to be thick enough to provide sufficient rigidity. The main consideration here is either to have a windscreen material which can provide enough stiffness itself, or have a thinner, lighter screen which needs a frame to support it.

  • Material

The main choice here is either to use glass, persepex or polycarbonate. While glass provides excellent scratch resistance it is very difficult to form in a one-off situation, it would be very heavy, and a laminated screen would be essential for safety reasons. The choice then comes down either to Perspex or Polycarbonate. Perspex is

  • Stiffness
  • Scratch resistance
  • UV resistance

I again had a stroke of luck that I was able to acquire a second-hand comfort windscreen in good condition. I based my design on the use of that windscreen.