The front fairing must shield the rider from wind, hold the headlights, and mount the instrument cluster, including GPS and maps. I'll be making mine in sheet aluminium, because for a one-off bike like this it suits my process very well. The ideal material might be a super-tough polyethylene plastic like road furniture is made out of, but the manufacturing process is one that is only viable at scale. Aluminium does present its own problems though, chiefly that it's tricky to weld. The aluminium welding process is a hybrid between brazing and oxy-acetylene welding steel with a rod, so I've invested a lot of time in the last week practicing both before my aluminium welding goggles arrive and I can get used to the true process. These special goggles filter the light in such a way that it's easier to read the temperature of the aluminium when welding, rather than just blocking all wavelengths like goggles for welding steel do. The fairing will be built in a similar style to classic Dakar desert racing bikes. That is, quite tall, sweeping round to meet the fairing, and mounting the navigation aids high and near your eyeline for quick reading. I'm initially prototyping in cardboard and hot glue. I found it very hard to design forwards from the tank, but much easier when I started to shape the front of the fairing first then worked backwards towards the tank.
The prototype is perhaps a bit too angular and not broken up enough at the moment. It's overall impression is very blocky... It will have at least some of the edges rounded off and joined together so they flow better. The aluminium will also be cut as a 'net' so as to reduce the number of welded edges. This may cause a bit more wastage in the material but will certainly help with rounding the fairing and avoiding an excess of hard angles. Some of the surfaces will also be rolled but its hard to demonstrate this in cardboard. In my previous post I discussed some of the reasons most modern adventure bikes are less than ideal to long distance off road travel. The question then is what would fulfil the criteria laid out... The ideal bike must be tough, light and not overpowered, carry its weight centrally, be easy to work on with basic tools, have a long fuel range, and be comfortable. I'm going to base my working prototype on a Suzuki DR600, and not just any Suzuki DR600, this Suzuki DR600 built in 1986! So why have I chosen this bike? It's already well regarded as long distance off roader and matches many of my criteria. With some work it will match all of them. The end result will
In subsequent posts I'll go into more detail on some of the modifications I'm making and how they're being fabricated. With access to well equipped workshops I intend to do all the work myself. In the meantime I've managed to tear myself away from riding the thing and the strip down has begun. The major parts of the frame, engine, suspension, brakes and most of the controls are perfectly good, but the rest (silencer, subframe, parts of the main frame, plastics, and tank) has got to go. This project to turn a 1986 Suzuki DR600 into a competent long distance exploring package is born out of the potent combination of two things: -A long held desire to 'build a bike' -A niggling frustration at the vast size, weight and complexity of both modern 'Adventure Bike' packages and older bikes converted to the task of true overland off-road (or at least off metalled roads) exploring. The desire is easy to explain; who doesn't!? But the frustration might take a little longer. Let's start by looking at three of the most highly regarded 'Adventure Bikes': BMW's 108hp 1200 GS Adventure: KTM's 150hp 1190 Adventure: and Honda's new 95hp Africa Twin: All three have been compromised by the demands of the market. Very few buyers use these bikes in the ways their looks might make you believe they're designed for. All three are overpowered, complex, immensely wide when loaded and carry that load very high. Let's think about each fault in turn... Overpowered The modern motorcyclist expects vast amounts of torque and power on demand, perfect for fast road use but totally unnecessary off road, especially long distance. Complex Neither buyers nor manufacturers can really be blamed for this. EFI and ECUs all make a lot of sense with garages and breakdown services never more than a phonecall away but make things rather harder to fix if anything goes wrong far from your local dealer. Wide Luggage packages for these bikes must fit onto racks, and these racks must fit around panels. And these panels must go over exhausts. And the stock silencers on these exhausts are generally large. High To retain space for a pillion passenger these bikes are forced to move a lot of the luggage far back and high up which compromises handling which would be much improved by a more centralised weight. Probably the most enlightened of modern manufacturers when it comes to 'proper' adventure bikes is CCM. Yet even their best effort, the GP450 Adventure isn't ideal in some areas. It's certainly not overpowered with the 40hp it derives from a 400cc single borrowed from Suzuki's water cooled DRZ, a figure I think is probably close to the realistic ideal for off road riding. The GP450 is also very light thanks to its aluminium frame, a benefit which cannot be overstated when it comes to terrain where the bike is guaranteed to be dropped at least a few times.
However it is still compromised in terms of how it carries it's luggage (forced to fit above and around all of pillion, frame, and exhaust) and also by the complexity of its water cooled EFI and ECU controlled engine. The last is only a very minor niggle though. So what's the solution to all these compromises? A topic for the next post. |
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