LAMBRETTA GEARING... SIMPLIFIED!
The Lambretta engine is a simple but ingenious design. It’s neat, compact, and when you think about it… not only does it house a chain drive but also a four-speed gearbox (now five-speed in some cases). To get all this in such a small area was quite a remarkable feat at the time of its conception. Innocenti was smart in how it went about the gearing requirements for each model… changing the ratios depending on the capacity and power output with great ease.
Here is where it gets a little complicated though, as models ranging from the Li Series 1 right up to the Grand Prix all had gearboxes that were interchangeable with each other. Chuck in the fact both the front and rear sprocket were also interchangeable and you have a vast amount of gearing options available. This is where people start to get confused. So the question is… which gearbox best suits a certain engine and what sprocket choice is exactly right to use with it?
What defines the gearing?
If you ask Lambretta owners what gearbox they have in the engine, some will not be able to answer correctly. Even if they do, chances are they will not know what sprocket combination it has fitted. When gearing is termed short or tall, or low or high, it quite often puzzles people. The reason
