Basic Help

The workshops at Cambridge Lambretta are always a busy place, many of the questions we are asked, the information is on our site so you don't have to wait to ring, e-mail or contact us. You might just need to have a quick, look for it.

So to hopefully save you time, this is a list of questions we often get asked, chances are one of the answers may help you! If they do not, or you need further help or advice, then do please feel free to contact us

These answers are not the whole truth and nothing but the truth,
merely our opinion and advice
right or wrong, better or worse



Petrol, Oil and mixtures
With the petrol you should use the highest octane rating you can find, Super Unleaded for example. The use, or should we say non use of leaded fuel does not really affect Lambrettas other then more heat build up as Lambrettas do not use valves etc. Lubrication is carried out by the fuel and oil mixture.

Lambrettas run a 4% mix as standard for their fuel to oil mix, that is they did in their hay day with the quality of oil that was available. If you run your Lambretta on mineral two stroke oil, continue to use 4%. However, with the newer blended or 100% synthetic oils, you can reduce this to 3% which as well as being cleaner burning, it will also reduced carbon build up smoke from the exhaust. The one thing to consider is that by running less oil, your Lambretta will run slightly richer due to the viscosity of the mixture, but this will normally be offset by the fact with mixture should run through the jets easier.


An oil measuring jug can take the guess work out of adding the correct amount of oil. These jugs give a 2% mix, so it is easy to add one and a half measures, or two measures depending on the percentage you require.
The SIP Squeeze Fuel-Oil Dispenser features all the different ratios you could need, in a non drip bottle making it clean and simple to use


Gear box oil
All early models including A, B, C, LC, D, LD, E & F run SEA30 in their gearbox. one half a lite will be adequate.
All later models run ST90, again a half a litre is sufficient.
Many owners will notice that in the manuals 0.7 litres is advisable, or fill to the level plug, whilst this is fine you tend to find that to much pressure can build up within the crankcase and put pressure on the oil seals, causing premature failure due to the age of machines. One important note is all S1/2/3 engines, the filler plug is also a breather plug, and care should be made to make sure the breather does not become blocked.


What colour?
If you wish to return your scooter to original, more often than not, your best place is to look inside the horn casting, as this paint rarely gets removed or subjected to the elements that makes paint fade. If this is so take it along to your local car (auto) paint supplier who will match it up for you. You will need to chat to the person/company who will carry out the re-spray, to find what kind of paint they use, (i.e. 2K cellulose etc.) also asking the type (speak to them for more details).

If you want to paint your scooter to original specification colours, we have compiled a list of colours here


Chassis and frame numbers

Early pre 1957 models, the frame number can be found on the right hand side of the frame. It is on the vertical part, just in front of the rear wheel. The engine number is also found on the right hand side, at the front of the engine near the two large filler plugs. On all S1/2/3 models the frame number is found by taking the kick start side panel off. On the main frame tube under the fuel tank, the frame number is found there. On some very early S1 models, the frame number was further forward nearer the tool box. The frame is always prefix with the model type, EG Li150*123456, and contains six digits. The IGM (Italian type approval number) follows this. Engine numbers can be found on the top of the engine, directly in front of the rear shock absorber mounting, but it is partially covered by the gear linkage and cables.

Where to find your frame number


Should I tune my Lambretta?
First we need to ask you a question. What do you use your scooter for? Around town, down the motorway (freeway), bit of both? In the UK, a scooter is mainly used for perhaps a daily commute to work now and then, and the odd 9 or 10 rallies a year. Two entirely different tunes are needed to satisfy your needs really one to give good acceleration around town (bottom end speed) and one to give good cruising speed (top end speed). As always a compromise is needed between the uses of your scooter. If ultimately you want reliability, no tuning is recommended (Innocenti after all did spend thousands, millions in today's money, designing, testing and refining you scooter). profiled heads build up too much heat, out and out tunes alter the appearance of your scooter and need the most attention to keep them running. If you do want to tune your scooter, then choose somebody with a reputable name to carry out your work, asking where necessary what happens if it all goes wrong, important if you do not have anybody close by to maintain and fix it. Ultimately you will need to look at improving the rest of your scooter as well, things like cranks, clutches, bearings, and not forgetting the brakes, as these will all effect the reliability of your scooter. Out and out tuning can be OK where done properly, but you will need to look after your scooter more, be prepared for increased wear and tear!


I have an electrical problem
95% of all electrical problems are caused by a bad earth or faulty connection(s)! Check and clean all surfaces and connections were the fault is. The reaming problems are usually the component itself, in which you will need to usually have this replaced if it cannot be repaired.

Almost all Lambretta models follow the same Lambretta family of wiring colour codes, these are :-

  • Green - Ignition
  • Brown - Main lights
  • Purple - Auxiliary feed, I.E Side lights, horn. N.B. If using an electronic loom, it will not have a purple, put the purple you have from the switch in with the browns.
  • Yellow - Side light, this will not work unless you feed power to the purple as above
  • Orange - Feed from ignition switch to light switch for main lights N.B Not on Li models, as the light switch does all of this
  • Pink - Earth for ignition switch
  • Black - power for the rear lights, plug the speedo black wire in with these
  • Red - Main beam
  • Blue - Dipped beam
  • White -  Horn earth wire, goes to switch to make the earth circuit.

That is it, Lambretta wiring really is that simple.