Ignition systems can also play a part in power, where it is made, and how well. Static timing on an original points and condensor system can only really cope with a certain amount of revolutions per minute, before the points cannot keep up. They have to open and close, being a mechanical part, they can “bounce” at high revs, meaning they do not spark when they are supposed to.

Changing to an electronic ignition is one of the single best upgrades you can make to your Lambretta. One word of warning though, is that almost all systems made on the market today, bar far the most available are made in India, and quality can be at best described as erratic. Poor quality of parts and workmanship can some time determine if you get a kit that will last, let alone work at all. Many suppliers re-manufacture and upgrade kits before selling to the public, so check with your supplier.

There are now alternatives coming on to the market, lighter flywheels, differing timing, but the progress is slow. One such kit called the Varitronic, improves quality and performance to what is currently available from India. The Varitronic features and advance and retard feature, a pre programmed power curve. The advantages of running a advance/retard system is that you can change the timing to suit the speed you are running at. For example if you run advanced timing gives so much more power but at high revs because the spark is so advanced, it will cause to much heat and burn a hole in your piston.

Static timing as found on most electronic kits really is a happy medium, you have to set your timing at a figure that still gives power, but on the other hand can also be run safely. With the variable timing kits, these allow the use of running advanced timing, and then when the revs rise the timing retards making it run not only at its best, but also its safest.

Flywheel weight also comes into play; most standard or electronic flywheels can weigh between 2.5 to 3and above kgs. This heavy weight has its good and its bad points, the heavy weight helps to produce torque once the speed is obtained, plus allowing a slower tick over with out the engine stalling. New lighter flywheels are now on the market which greatly helps in terms of acceleration, but need a higher ticker over. To light or to heavy can also put strain and stress on your crankshaft, in certain circumstances cranks are not unknown to twist or snap under load. Ideally a Lambretta flywheel should around 1.80 to 2.kg.

The basic Lambretta air filter is quite basically designed for basic engines; any increase in performance can cause restriction in air flow. Although there are a number of ways to help this, such as drilling air boxes, widening the air scoop and neck, the basic make up of a paper air filter can still restrict air flow.

This will cause problems in getting jetting correct as well as restricting performance. The main problem with the air filter box, is that air needs to be held in reserve, look at it as a being like a fuel tank, if there is not enough air in the box, when your engine needs maximum air, the air filter system cannot keep up and runs dry for want of a better word. We all fit fast flow fuel taps, but then neglect the air system. Also the nature of the paper air filter element is not the best method of allowing high air flow,

The are two other filters on the market other then the standard type. The first is a high flow item, still looking like the original filter, and still fitting within the standard Lambretta air box. The second is a remote filter; this normally involves using a Lambretta carb to air box rubber and bonding on a general purpose after market filter from companies such as K&N or RamAir etc to improve flow. Depending on your set up, jetting etc etc, tests we have done can see any thing from ½ to 2bhp more by switching air filter systems.

Cylinder Tuning and kits
Increasing CC by Re-bore Iron cylinder

Performance can either gained by increasing the CC of your scooter, or by tuning the ports to give more power. With the arrival of cheap cylinders from India, it has become no longer viable to tune or increase the cc of your original cylinder. 125 cylinders can be taken out to 150, 150 cylinders to 175, 175 to 200 and 200 to 225. You can in certain instances increase cc further beyond these guides, but in general the cylinder walls become dangerously thin, and the cost outweighs the gains you would get. As we said, it has now become pretty much as cheap just to buy a complete bolt on kit.

One thing to note with the wave of cylinders coming in from India, although they are on the whole good quality, and most can be bolted on straight from the box to give some form of improvement, you can make further gains with some simple tuning and modifications. One point to note is that many of the 175 cylinders can infact give poor performance, as these have small inlet, exhaust and transfer timings. Bolting one of these cylinders on such machines as SX150, GP125 or 150 can sometimes see no or very little gain due to the porting.

Porting Iron cylinder
Porting your cylinder or as most call it “stage tuning” can be an effective way of gaining speed. Porting normally involves making the inlet, exhaust and transfers larger, a word of caution though, you cannot just open them willy nilly to what you think will be correct! If you are considering carrying out such work, we would suggest you either have this carried out professionally, or at least seek to purchase a tuning manual to guide you.

Cylinders Kits Mugello Kit
Bar far the easiest and most effective way of increasing performance is to use one of a whole host of bolt on kits that exist on the market today. As well as the Indian 175 & 200cc kits already mentioned, you can choose from iron, alloy with a cast liner, or alloy with internal plating.

For the 125/150/175 cylinders, currently there is a choice of :-

175 kit
Usually a waste of money for most engines, as the porting is not very good on these cylinders which can lead to you going slower then when you started! Many shops offer further tuning on these cylinders, which then give them better performance. With the poor quality of todays pattern pistons, heat seizures are comon if you do not look after your set up impeccibly! This means following correct running in, and even after that no hard and fast thrashing it, and keep the correct oil quality and ratios of oil. Bargin bucket end of performance stakes, only buy this option if your on a tight budget.

SR175/190cc
These are an alloy cylinder with a steel liner, no better performanve then standard cylinders unless tuned further, which can be tricky due to steel liner. The price of the SR kit is very low, and so it is worth considering if you are on a budget.

GT185cc
Iron cylinder with reed valve, good all round kit, but one of the most expensive kits

Mugello 186cc
The Mugello is an excellent all round kit, which is equally as good standard or tuned with larger carbs and exhausts. The good quality piston and nicasil lining allows for more reliable operation

Imola 186cc
Imola 185cc is an alloy cylinder, nicasil line with reed valve induction, and is probably the fastest option for these casings. The the tuning and developement carried out on the Imola, not only is this kit very reliably, it can also give the larger cc kits a good run for their money for performance. Because the Imola piston is smaller and lighter then larger cc kits, together with the porting and a well matched set up, horse power and acceleration figures can often match and be better then other kits of much larger cc.

For 200 engine casings, there is equally a large choice to ponder.
Rapido 200 & 225
Alloy cylinder with a steel lining, you can get race and classic versions of the Rapido. Port timings on the race promote a very revvy engine, and large carbs and revvy exhausts are needed to make this kit perform.

Mugello 200 & 225
The Mugello is like its smaller brother a good all round kit, for the larger casings the kit comes in 200 & 225 off the shelf.

TS1
The most well known kit of them all as this has been on the market since the mid 1980’s . Proven performance, alloy cylinder, nicasil lined and reed valve induction. Has been hard to find lately as the kit did go out of production for some time. Although good, we prefer the Monza kit due to the Monza’s supirior transfer ports, and slightly less revvy nature.

Monza 200 & 225
Very similar to the TS1, but with the addition of larger transfer areas for better tuning and porting. The Monza also benefits from a very well made piston, which is very light and strong.

The problem with most Lambretta sets up is to gain the best possible inlet of fuel; you would not start of with the inlet area of the cylinder where it is. A direct route for the fuel/oil/air mix will give the best results, but most inlet manifolds feature some form or curve or slight bend. Some of the early CDC type manifolds for large PHBH Dell’Orto cars we amongst the most direct on the market, but their draw back was they would not be able to run through a standard Lambretta air box.

Also being solid mount, with vibrations this caused problems with the fuel in the float bowl, and supply of fuel to the engine. There are and have been quite a few manifolds on the market that while also being direct, also allow the use of the air filter box, but they tend to depend or application or parts used. This last statement also pretty much holds true as to what you can use, as your cylinder and carburettor dictate what can and can not be fitted, again speak to your supplier if there is a choice!

Using a rubber manifold, or at least at manifold capable of using a rubber mount between the manifold and carburettor is quite important on a Lambretta. This is due to Lambrettas vibrate, rubber mounting the carb helps cut vibration down, which can lean to fuel frothing.

Tuning theories differ greatly on carbs, in the past the theory big is best with carburation is not always the case. Smaller carbs tend to promote torque and cleaner running, larger carbs tend to promote more top speed, at the expense of bottom end power. You can as with everything in life go to small or to large, either starving the engine, or flooding it, again you need a happy medium.

Many tuners of two strokes have started using simple carburettor designs of smaller diameters, as getting the jetting correct on a two stroke can be the difference between an engine performing to its full potential, or being 4 or 5 hp down on well tuned engines. In general size of carb needs to be chosen by the cc of your scooter, level of tune, the air intake system and the exhaust, not just one factor.

The most common carbs on Lambretta are Dell’Orto, both in terms of standard and bolt on performance types. But there are increasingly more and more different makes entering the market for use with Lambrettas, so again the choice is wide and varied. Many claims are always made of which carb is best, gives you most power, easiest to use etc. We have worked with Dell’Ortos for many many years, and these have proven time and time again to give the best all round results. The Dell’Orto carbs come with probably the largest selection of spares of almost any make of carb.

Standard items are for all Series 3 Lambretta machines from the SH range of Dell’Orto carburettors. Although no longer manufactured a huge amount of spares both new and second hand are still available. The smallest bore on the S3 Lambretta is the 18mm. then going up to 22. After market and bolt on carbs can go from 22 right up to 34, although you can and there are larger carbs then this, in general larger carbs tend to be too much for the humble Lambretta!

Carburettor sizes and recommendations vary from tuner to tuner, it is probably best to speak to your chosen supplier and see what they recommend. Roughly speaking

125 to 150cc keep the original carb, possibly go to a 22mm
175 (tuned) 22 to 28
200 + (tuned) 25 to 30

When the mention tuned, we mean by means of porting, exhaust, etc.
On more exotic kits such as the GT, Imola, TS1 etc, you need to follow your suppliers recommendations, as they tend to run on differing carbs.

99% of all two stroke tuners will agree with biggest gains or losses for that matter can be made with exhausts. The exhaust really controls where how and when power is made, from a low revving exhaust that makes lots of torque (pulling power) to a high revving exhaust that makes lots of peak power (speed).

For instance using a high revving kit or port timings, but bolting on a low range powered exhaust probably isn’t the best idea as one is fighting the other in terms of the way they work. Although having just made that statement there are certain instances where you could do such a thing and it would work well!

Building the perfect exhaust depends on what you use your scooter for, many exhausts exist on the market for Lambrettas, and they work in different ways. Low revving exhausts tend to be good for touring, and longer distance work, they will restrict top speed to a certain degree because of this. It is important to remember that the fitting of an expansion or performance type exhaust normally requires at the least a change of the main jet, you should ask the supplier for details for your exact specification of scooter and what is required.

Low revving Exhausts on the market. Good for touring, gearing can also be kept taller.

Taffspeed
JL Road
Ancillotti / Big bore type

Mid range exhausts are generally used for all round use, bit of acceleration, plus a bit of touring.

PM tuning
JL Race

Higher revving exhausts give good acceleration and top speed, but tend not to be as good for touring as the scooter is revving higher to achieve the same speed. The engine revs need to be kept higher to achieve the performance, best to use low gearing.

Imola snail
Scorpion
NK