Specials Building.

Specials Building.

(c) Tony Foale Aug. 1987 – 2022

( 2022 note )The documentation part of this article describes the situation as it existed in Britain in the mid 1980s and will possibly be a bit different now and will vary from country to country

Here we are again, ——– autumn’s coming and then winter will soon be upon us, the traditional time for specials builders to sharpen the cold chisel and put a new blade in the hacksaw. Specials take many forms and are built for just as many different reasons. Some are to give vent to their creator’s artistic fantasies, others are built for more functional reasons —- perhaps to go, stop, and/or handle better, there are also those built to test some theory or pet idea. None of these reasons are mutually exclusive, and many specials include aspects of all. The creation of any special can be extremely satisfying, as well as frustrating, whether it be the installation of a Triumph twin engine into a Norton Featherbed frame with Dunstall swept back pipes (the sixties favourite with many people), or the construction of a completely new machine with its own unique engine as well, —– as difficult as this may seem it has been done by several people in the past, and often with surprisingly primitive facilities.

So don’t be put off the idea just because you do not have a ten thousand square foot workshop at the bottom of the garden, stacked high with CAD/CAM equipement. Mum’s kitchen table has probably spawned more specials anyway. I started building my own machines literally within weeks of getting my licence and for several years had no more than a large packing crate in the garden, in which to wield the welding torch. So if you want something different then have a go, but be warned, it can be quite addictive and it seriously eats into one’s drinking time, for there is one common theme that runs right through the middle of any such project, whether it be a low budget student’s bitsa or a no expense spared show bike for a major manufacturer, and that is —— TIME and lots of it. Generally, it is not the major parts that use up this irreplacable commodity but all those apparently insignif icant little details so necessary to finish the machine of nicely.

Specials building is never totally plain sailing, regardless of your competence, there are many things outside of your immediate control, designed to frustrate your efforts;— for example there may be difficulties with getting materials in small enough quantities, being sent unsuitable parts, getting the painting back and finding the wheels black when they should have been green and the frame green when it should have been red, etc, the list can be endless. But it has been my experience that despite these real difficulties, the two biggest worries for most people are perhaps the easiest to sort out, i.e. the documentation and electrics. If these seem like insurmountable hurdles to you then read on;——-


Up until a few years ago, there were two ways of getting your creation on the road with a legal number plate. If only a limited number of items on the bike were changed and if it had been previously registered, then you simply retained the original number and advised your insurance company of the changes. However, if the changes were of such a magnitude that the original bike lost it’s identity, or if the machine was built from parts not readily attributed to one particular bike, e.g. new frame kit and an engine from the breakers, then you were required to register it as a new machine and get a brand new number. This was fine until the government decided to impose “New Car Tax” on NEW motorcycles. That meant an additional payment, on top of the road tax, of 10% of that figure which the Customs & Excise Department assessed the wholesale value of the machine to be. Confused? Well so was everybody else. Eventually the powers that be, realised that there was a need for a third class of vehicle registration and the ‘Q’ plate was born. This was certainly not introduced to relieve specials builders of the burden of ‘new car tax’, rather it was an attempt to cut out the fiddles of re-registering insurance writeoffs and older imported vehicles as new machines, and hence artificially increasing their value. The ‘Q’ plate system recognises that there are legitmate cases were a vehicle needs to be issued with a new number even though that vehicle is not NEW in the true sense of the word, i.e. a special built largely from used parts. To get a ‘Q’ plate for your new toy is not difficult but as the system is administered by civil servants, you can expect to get your share of “bureaucratic induced frustration”, or BIF, this deadly disease speads quickly , and it is not often subject to the correct diagnoses.

On the afternoon that the editor and I attempted to get the Q2. registered we were both exposed to large doses of this virulent plague, fortunately I have built up a degree of immunity over the years due to previous encounters. Tony the younger, however caught it pretty badly and it was only the more immediate physical problems brought on by the ingestion of the offerings of the local greasy spoon that saved him, but more of that later!

The registration of your special will be handled by a LVLO (local vehicle licensing office — for the uninitiated), these can be found in your telephone book under “Transport, Dept. Of — LVLO.” In my experience each office has slightly different ways of handling applications, so ring them first and try to speak to whom ever is in charge of the ‘Q’ plates. You should ask them to send you a couple of forms, viz;— a V55/5 which is “Application for a First Licence for a Motor Vehicle and Declaration for Registration”, and form LVLO 363 which is “Vehicle Registration – Rebuilt or Kit Vehicle Construction Details Report”. Find out how your particular office would like you to go about the procedure. In addition to these forms you must get an MOT certificate, an insurance cover note and receipts for all major items, particularly engine, wheels and frame. These receipts should bear the name, address and signature of the person or firm that you bought them from. If you made the frame yourself, then just tell them, but you will need to have a frame number stamped on it regardless of its source. So if it didn’t come with one then just make one up, JBF/001 (the Joe Bloggs’ Folly no.1) for example.

Normally an MOT certificate will record the registration number of the machine, but as you need the MOT prior to getting your number the frame number will be used instead. One point about getting the MOT, is that provided you have made an appointment with a testing station beforehand it is quite legal to ride the bike there without a registration number, but make sure that you have valid insurance cover though. When you have all the required paper-work together it will be necessary to visit your LVLO to complete the formalities and have the machine inspected. Some people are apprehensive about this inspection, imaging some form of super MOT test. In reality it is purely a check to see that the engine and frame numbers correspond to those on the forms. In other words to check that the bike being registered is the same one as recorded on the documents.

To illustrate the procedural differences between LVLOs, I normally deal with the Maidstone (Kent) office as it is the nearest. Here they require you to send the documents in to the office in advance of the test appointment, perhaps up to a week beforehand, apart from this sometimes tedious delay I have never had any other problems from this particular LVLO. In contrast to this office I rang a London one when trying to get the SuperBike Q2. registered quickly and was told to just bring it along with the paperwork and they would sort it out on the spot provided we were prepared to wait for a hour or two. I had heard that Guilford also operated in this way and as this was closer I gave them a ring on the Thursday before the GP. at Donington, an event at which the editor wanted to pose with the new Q2, they confirmed that I had been told correctly. SuperBike’s super sec. Sara also checked with the Wimbledon office and was told that it too could do the job when required. We had been waiting on the post for some jets to arrive, but as there was no sign of them on Thursday we decided to wait another day before getting the registration sorted out. But Friday’s post brought no joy either so we stuck the machine on a trailer to take it to the Guilford LVLO. Before setting off we prudently phoned to check that it could be done —– FAT CHANCE! —– “Sorry mate, we don’t do the inspection here, that’s done elsewhere on an industrial estate.” — “O.K.” I said “Where’s that, we’ll go there.” — “No you won’t.” stated the anonomous voice of officaldom — “They only see people on Thursdays, and they are booked up for the next two, anyway.” —— Arrrrr! Why didn’t they tell me that yesterday.

Not to worry, we’ll just go to Wimbledon. Half way there I realised that some forgotten distraction caused me to forget my intended confirmation phone call, shouldn’t matter, after all Sara called them yesterday. So after a very slow, steaming drive through heavy traffic on what seemed like the hottest day of the year we arrived full of expectation. The Q2 project bike will soon be legal! I had warned TM. that as it was the last day before the great ‘E’ registration plates came out there might be a considerable wait in store. But no, spirits rose as we entered, the office was almost deserted, the two customers being easily out numbered 5:1 by the staff. After a short ten minute period of being completely ignored, one of the staff generously put down his Beano and came to the enquiry window. I honestly believe that we made his day, —- Sorry, we can’t do your bike today, don’t you know that this is the busiest day of the year for us.” —- “But the place is al most empty.” —- “No, much too busy.” —- “But Sara called.” — “Who did she speak to then?” — “Don’t know.” — “Sorry, can’t help then.” — After much grovelling and pleading, I thought that he might be relenting, perhaps he finally realised just how influencial TM. was. — “If you would like to wait until the lady who does the inspections returns from lunch …..” — “Yes, yes,— she’ll do it for us?” — “….then she’ll be glad to make an appointment for next week.” —- It was just as well that he was safely stuck behind bullet proof glass.

The moral of this tale is simply not to expect the wheels of officialdom to move at your pace.

Insurance can some times be a bit tricky with specials. Third party is usually no problem but fully comprehensive may be. There are two basic problems,

1. insurance companies are suspicious of changes to vehicles, and

2. the value or your life’s work may be much higher than the book value of the donor bike. This can greatly affect your compensation if you have the misfortune to seriously damage it. For example, if your special is worth £10,000 but was constructed from a 5 year old machine with a book value of £1,000, then the insurance company is unlikely to give you more than £1,000 should it be totalled. The way around this is to take out an agreed value policy with the company. You may need to shop around to find a company willing to do this, but more seem to be interested in this type of business. They will probably want their appointed inspector to check over the machine to ensure its roadworthiness and confirm its value. The premium will almost certainly be higher than for a standard policy and you must decide whether it is better to pay up or carry the risk on your own shoulders. If you built the bike then perhaps you can repair most damage cheaper than the premium.


A glance at the wiring diagram of any recent super bike is enough to dissuade just about anyone from attempting to reproduce something similar for their pride and joy. But why should the wiring be so complicated? A ten year old bike will in all probability have a much simpler wiring loom, with the same functions to perform. e.g. Both the old and the newer bike will have a starter motor, ignition, lights, stop light, horn, kill switch, indicators, a charging system and a few warning lights to operate. The modern bike will probably have a fuel gauge, maybe also pre-start check indications and a series of interlocks to prevent the starting of the engine unless the side stand is up and neutral is selected or the clutch pulled in. These few differences do not seem enough to explain all the extra wires in the loom, but that’s the way it is.

Most specials seem to be short of space for the electrics and the use of a standard wiring loom often causes difficulties or is just plain impossible. In most cases I think that the best way out is to start from scratch and make a new wiring loom. I have a passion for simplicity, be it mechanical or electrical, and I loath to have to include items that have little functional benefit, such as the starting interlocks etc. In my humble opinion any idiot who doesn’t know when it is safe to press the starter button shouldn’t be allowed near the bike anyway. Still, each to his own, and it is up to you to decide what hardware and functions to include on your own machine. The next step is to decide on the location for the various bits and pieces, these include coils, ignition box, horn, regulator/rectifier, fuses, relays, etc, etc.

Some machines place these various components where-ever there appears to be a bit of room, others tend to centralise their position, perhaps mounting most of the bits on a single plate. The old Kawasaki Z1 series did this quite well. I tend to use a bit of each technique, preferring to mount the starter solenoid near the battery to keep the heavy wires to the starter as short and direct as possible, and as most regulator/rectifier units only connect between the alternator and battery I usually mount this close by to keep this wiring to the minimum also. Lights and indicators will need to be mounted in fairly obvious places and the horn where-ever it fits. The other components with the possible exception of the ignition coils, I like to mount on a plate. This often has the advantage that much of the required wiring is between these various bits and so the number of wires to other parts of the bike is kept to a minimum. To make for easy assembly/dissembly and possible future modification, I like to have the outgoing wiring from this plate connected through multi-pin plugs and sockets, the latter being mounted on the plate. The old Kawa. Z1. series did this much better than some current machines.

If you don’t have the confidence to think of the electrics as a whole, then just divide the wiring into individual functions and treat each one separately, most functions are independent of each other, save for the supply from the battery. The diagrams show how simple each circuit can be. Just concentrate on wiring up and testing each item on its own. To aid making the correct connections at each end and also to assist subsequent fault finding, it is only sensible to use different colour wires and the best source for this is your original loom if you have one, or strip one from a car at the local breaker’s yard. The car one will contain more wire and will probably be cheaper. In fact there are several components that can best come from the car world if you do not have them already, — relays, fuse boxes and indicator flasher units to name but three. Flasher units in particular can be expensive from a bike shop and they often do not last all that long, whereas I have found the two terminal Morris Mini type to be compact in size and price (about £2 each) and they usually last for ever.

Fuses are not essential and they do add complexity but I think that it prudent to have at least some to protect the circuits. Otherwise in extreme cases, and they do happen, a fault may cause a fire which could destroy your irreplacable cycle. Relays are another non essential but they can be worth while for the head lights and ignition circuits.

Before reaching its destination the current from the battery has to negotiate many obstacles which result in the reduction of this current, in other words the voltage across a particular component will be somewhat less than the voltage at the battery. This voltage drop can cause significant reductions in the performance of some functions. This hinderence to the free flow of current is known as electrical resistance and has many sources, for our purposes the main ones being ;—- connections, the wiring itself and probably the worst offender is switch contacts. The ignition circuit usually has at least two sets of contacts to negotiate, viz; the ignition switch and the kill button.

The headlights may have three sets, — the ignition switch, the lights-on switch and then the dip switch, so it’s little wonder that I have often measured voltage drops of 2 to 3 volts leading to these items. This represents a drop of 15/23% of the battery working voltage of about 13V. That can sound bad enough but the energy in the spark or the power of the lights depends on the square of the voltage getting to them. So on that basis the above voltage drops mean a reduction in performance of these systems of 28 to 41%. No wonder that some people find it necessary to fit higher wattage bulbs and expensive high performance coils. You cannot eliminate all of this loss, but by using thick enough wire, few connections and good quality relays the loss can be reduced markedly, the voltage drop across good relay contacts will normally be much less than across the puny contacts in the handle bar switch gear, particularly after being exposed to the rigours of our glorious weather. The figures show the differences required in the light and ignition circuits to incorporate the relays. A slight complication but in many cases the performance benefits compensate, you may even get better results than buying expensive coils, although of course the pose value is inferior. After all, a single pole. 30A. contact rated 12V. coil relay is much less likely to impress the impressionable, than the latest high tech flame throwers from the States.

By now you should have decided what you what to include in your wiring. There are many ways of going about the loom construction, but for the inexperienced I would suggest that you simply lay out the wires between the various components that need connecting together. Try and run the wires neatly together and connect up each system in turn. Finish and test all the indicator wiring before moving on to the lighting system, for example. When you have completed this stage, the bike will look a complete mess with wires everywhere, but don’t worry because once you have checked that it all functions correctly, it can be tidied up. There are several ways to do this, Feeding the wires through plastic tubing can be quite neat and BMW used to favour this method but it can be arkward to do by hand if you have several wires already fitted with spade terminals. The Japanese seem to go more for taping their looms together, but this is not ordinary black sticky tape, but a more expensive variety know as self-consolidating tape. With care you can do quite a neat job with this stuff but its application is tedious by hand. The tape must be wound on under sufficient tension to reduce the width of the tape to about 1/2 of its normal size. This can be very boring and time consuming and it is difficult to neatly add later modifications. Another disadvantage is that after some years it seems to dry out and starts to unravel itself.

In my opinion the best compromise for one off looms is to wrap them in a plastic spiral, which can be obtained from some electronic stores. Goodridge the brake hose people, stock it for protecting their hoses. This sprial can be wrapped around any thickness of loom and is thus more universal than plain plastic tubing as well as being easier to use. Changes are easily incorporated and repairs facilitated. Done well it can look very neat. In addition to this plastic wrapping another useful product is trailer cable. This is available from most car accessory shops and can be obtained in 5 or 7 core, each wire a different colour. This is particular neat and is useful when you need several wires to go from one end of the bike to the other. I find it extremely good for getting the power to the rear end for the tail lights and indicators.

There are countless other things that could be said on this subject, but space precludes them, just remember that the wiring is not particularly difficult it just needs a bit of care and common sense.

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