AT LAST ?

AT LAST ? ALMOST!

TM. has been wandering around with a small smile on his face lately. The reason for this unexpected occurrence is that at long last he is starting to believe that he will soon get his hands on a new toy, --- oops, should have said "Magazine Project Vehicle". It's only a small smile because the colour is not quite the Honda CBR. red that he wanted, as for me, the colour fidelity is of secondary importance, I am lost in admiration for the standard of finish on the paint provided by Derek George of FASTLANE up there in Manchester, and he was so quick too.

Perhaps the Editor's. smile will lengthen by next month when with a bit of luck, he'll actually get to ride the beast. But for now, both you and he will have to be content with the glossy pics. For newish readers, those with poor memories and those who only bought the mag. because of the front cover, perhaps a brief recap of the project is in order. ------ In last years May issue SB. ran a competition amongst the readers, to design the bodywork for a posers orientated futuristic project bike. The dirty bits and things that go round and round to be designed and built by yours truly.

From about 100 entries the chosen one was by Dan Parry-Williams and was featured in the August 1986 issue. The pattern work for the body was mainly built by second-placed entrant Bob Blackman (that'll teach him to come second). Since then construction of the device has proceeded at a pace which seemed akin to that of a snail, to those that didn't have to dirty their finger nails on it. Having managed to miss TM's. preferred deadline of the TT. I began to run out of excuses and so at long last here it is:--- well almost, nearly!......

Previous progress reports have described most of the features of the machine, but a few things have changed since then and the instrumentation has been finalised, so only these items will be discussed this time.

MAIN FRAME

This was originally to be a "C" shaped fabrication as fitted to Paul Griggs' machine (see March '87 issue.), this concept was developed for the older air cooled Kawasaki engines which have substantial mounting points on the head to which could be attached the steering mechanism etc.. However, on the Suzuki engine a lack of such mountings necessitated a rather untidy super- structure, but with the benefit of the lessons learnt from building Paul's bike, a rethink lead to the solution shown in the pics. i.e. a fabricated structure OVER not UNDER the engine. Not only does this blend in better with the styling but it is easier to assemble a light chassis over the engine than to lift a heavy lump into the frame. A super-structure is still needed for the steering support but this is much simpler.

FRONT SUSPENSION

There have been a couple of changes in this area. Firstly, the suspension unit location has been changed from the lower swing-arm to the upper wishbone. There was a two fold reason for selecting the previous position, -----

1. The early plan was to use a single link front suspension system, with just one arm mounted at about hub height. A design of this nature introduces a number of untested variables and the probable developement time necessary, indicated that a more reasonable approach was to use my double link arrangement as proven on the QL. With only one arm available the choice of suspension location .was more limited.

2. It was thought that if the suspension unit was mounted low down, perhaps less constraints would placed on the body design. In the event, with a bit of fiddling and an extra moulding it has been possible to fit the springing to the top wishbone, and still fit within the bodywork. I prefer this arrangement from the structural viewpoint as it does not subject the lower arm to vertical bending loads. Due to the assymetric shape of this arm these bending loads result in a very complex stress pattern, with a combination of torsional and bending strains which complicate the stress analysis somewhat and makes prediction of the failure conditions more difficult. Without the influence of the suspension forces to worry about the strength design of the lower arm becomes much easier as it is only subjected to bending loads in the plane of the arm, these loads arising from braking and any side forces fed in at the tyre/road interface. An efficient structure for dealing with this type of loading is an "I" beam, and as luck would have it this is also a very easy shape to cast. So another change to the front setup is the use of a cast aluminium swing-arm instead of a sheet steel fabrication.

As a consequence of these mods. to the design a useful weight saving has been achieved. Apart from the structural aspects, repositioning the suspension unit has freed some space in front of the engine which now allows the installation of cooling radiators. This no longer restricts engine type to the air cooled variety, both the Suzuki oiled cooled and the Kawasaki water cooled power units can be pressed into service. Were it not for the extra delay, that would be introduced by the time needed to make the pattern equipement, then we would have also cast the rear swing arm as well. But, whereas the pattern for the front one was very simple the rear is another matter due to the hollow sections needed. Still, that is something that can be added at a later date.

INSTRUMENTATION.

Although using micro-chip technology the instruments have been kept quite basic and simple, no pre-start self analysis sessions here. If that's your bag then see a shrink before donning helmet. There are digital displays for MPH and RPM with an electro-mechanical counter to tot up the miles, idiot lights are used to monitor the following funtions;----- Oil pressure, neutral, low fuel level, and high beam indication. There is no need to have an indicator repeater light because when riding Paul Griggs' machine I noticed that one can see the front indicators themselves and they are far more efficient at warning you that they have been left on than any warning light.

Personally, I would like to see a charging indication of some form but Suzuki do not make provision for this with their regulator, however this can be rectified (no pun intended) without too much trouble. LCD displays have been chosen for the speedo and tacho, instead of LED, because of the difficulty of reading LEDs. in daylight. There is insufficient space to mount them down a long dark tunnel which works quite well on the QL.. LCDs. have the opposite problem of being hard to read at night, but this can be solved by back lighting them with electro-luminescent panels. Most LCDs. that you see fitted to mass produced consumer goods are custom built for the application, but obviously the number of Q2s. that will be built will come nowhere near the figure necessary to have this option. Compared to LEDs. which can be bought in several colours in individual units enabling much flexibility in visual layout, the available range of off the self LCDs. is more limited.

None of these proved to be entirely suitable as they came and so some micro-surgery has been necessary. I can vouch for the fact that modern miniature electronic devices are not designed to be easily modified with scalple and magnifying glass. Most digital instruments work by displaying a reading for a set time, rather than continually changing as in most analogue meters. This set time may typically be about 1/3 to 1/2 of a second, the reading shown being the average measured during the previous time period. This is OK. at a steady speed as you can get a nice steady accurate reading, which is easy assimilated. But digital readouts can be disconcerting whilst changing speed, particularly on a motorcycle with its capacity for great acceleration. The speed change possible between display updates means that the reading will jump alarmingly and give the impression of inaccuracy, this is mainly a problem of getting used to the novelty, in reality we usually only need to know our speed under steady conditions. In any case an analogue reading will usually be lagging behind the true speed under changing conditions, its just that the steadily changing nature of the display gives the impression of accuracy.

Another electronic gizzmo on the bike is a bank cash dispensor type keypad instead of ignition and light switches. At first thought a bit gimmicky perhaps, but it is not without practical benefits. Firstly, there is no need to have a key wearing a hole in one's pocket, and the possibility of its loss is irrelevent. Secondly, a potential thief is unlikely to guess the correct combination from the thousands possible, to further hinder his evil ways I have programmed in a time delay (NO! I am not telling you how long) before it will accept another attempt at the correct sequence. So any potential unauthorized new owner will just be adding time delay on time delay in his efforts to find the magic number. The average joy rider bike thief would have a brain hemorrhage at the thought of trying to hot wire such a device and the profession thief will just lift it into a van no matter what you do, anyway.

The keypad is operated as follows;--- a four digit number ( PIN ) must be entered in the correct sequence to "activate" the system, once this is done, three single keys control the ignition, parking lights and main lights. One press to turn these things on and a second press to turn them off. Another key is used to turn every thing off, except for the parking lights which may need to be left on when the bike is unattended. To counteract the effects of prying fingers the parking lights can only be switched off by first entering the PIN to activate the bike. The horn, starter, indicators and dip switch are all mounted on the handlebars in the usual fashion. Well, that's about it for now until TM. gets his leg across it and tells you what its like to ride.

But don't forget that this was not intended as a one off special but as the first ( it turned out to be the second in reality ) of a series of exclusive handbuilt ego boosters. So if you would like one too, then morgage the old mansion because with sufficient inducement of a pecuniary nature I could look on your request with favour.