lui 50 to 75

The lui range is not just a ground-breaking design, it is also a hell of a lot of fun to ride. At least as long as the engine is not to original specs. The original 50 cc engine is a pain with 1.5 hp at the crankshaft and a top speed said to be 38.5 km/h / 24 mph.

Compared to the lui 50 the 75 models are a much more grown up affair. The big headlight unit with hi and low beam, a rear brake light and other features make it look much more grown up. And also work like that.

Thanks to the hype and craze about the lui range probably started with the first Lui Dolomiti Experience the spare and tuning part situation is better than ever. And you can easily turn your 50 into the specs of the 75 one.

For more details here is the model history for both models in one link:

We started a wish list with the major components to carry the conversion out:

Also in this listing is the new Casa Lambretta 80 cc kit. We did something on that before ->


Finally, we had it on the dyno with the SH20 original carb, air filter box and the lui 75 original exhaust. The SH20 was jetted like this for best performance and reliability:

Main jet:             65
Idle jet:                48
Atomiser:            5899-5

A very good result with the Innocenti prototype turned into reality by Casa Lambretta. Especially considering this test earlier with the 75 cc cylinder kit give a maximum of 4.9 hp at the rear wheel. At here we have on a fresh -not settled in- engine and kit 5.5 hp straight away. 

If you fancy more power on a 50 cc or 75 cc lui engine the Casa Performance ONE05 kit is the way to go. We also tested it with on the lui 75 with original exhaust and the SH20 carb.

With the standard 75 air filter box the jetting of the SH20 was:

Main jet:             76
Idle jet:                45
Atomiser:            5899-5

With a modified 75 air filter to 6T's Tuning Manual spec the jetting of the SH20 was:

Main jet:             85
Idle jet:                50
Atomiser:            5899-5

And on the dyno with the later setup it looked like this:

So some choices here and we have -sadly- not yet tested the ONE35 kit!

So stay tuned!

Drawing original Inocentti

new cylinder Lui and J50

Here we have put the 75 ccm tuning cylinder for the lui & Junior 50 models through its paces: CLICK! 

Since its appearance in 2009, the 75 has been an extremely popular means of giving the 50cc engines a boost.

The successor is now in the starting blocks, the 80 ccm CASA LAMBRETTA cylinder for those models.

Who now thinks: "WOW, 5 ccm more... What's going on there?" Not sooo fast!

In issue 22 (November / December 2020) of the ingenious ScooterNova Magazine by Andy there is the following report with the caption below:

"EXCLUSIVE – How Innocenti planned to factory-tune the Lui range"

Innocenti's technical drawings are dated May 24, 1968 and titled CILINDRO MOTORE 75cc SOLUZIONE with 3° TRAVASO bezeichnet.

The overcurrent system has been optimized with two finger ports and corresponding recesses in the piston, and the cylinder delights with increased torque in the medium speed range and revs further.

The cylinder from the technical drawings will reach us very shortly. Vittorio Tessera from CASA LAMBRETTA turned Innocenti's plans into reality and made the 80cc cylinder a reality:

New cylinder - CASA LAMBRETTA 80cc - Lambretta Lui 50, J50 CLX3

And here is the link to the shop: 

As soon as the new cylinder Lui and J50 is with us, it will be put to the test and will compete against the original 75 ccm lui cylinder and the old 75 ccm CASA LAMBRETTA cylinder, then we can report in detail.