With Charlie Edmonds now producing 6-speed Lambretta gearbox conversions, the Visualiser has now been modified to show 6 ratios, along with RPM drops for 4th, 5th and 6th gears.
This latest version includes Performance Tunings 4, 5 and 6 speed offerings with a number of configurations where alternative gears are available. You can fully explore the range of configurations using the custom gearbox feature.
Download the latest version here (MS Excel or similar required)
If you want to reference gearbox data on the fly without having to fire up a laptop and Excel, or simply don’t need the scope and complexity of the Visualiser, there’s now a “Lite” version for every known gearbox that’s optimised for smart phones.
You can run this as a web app for your phone (or tablet) to give you a wide range of data in your pocket.
The data currently includes:
The tooth count for every known gearbox (and all variations)
The percentage jump between gears
The final ratio in top gear for every sprocket combination
The MPH/1000RPM in top gear for every sprocket combination
The estimated chain length for every sprocket combination
Whilst the content remains on WordPress, I have a new easy to remember domain “LambrettaGearbox.com” and a new YouTube channel where I’ll post videos on the functionality of the Visualiser as well as examples.
There’s never been a better time to own a small frame Lambretta given the products coming out of RLC/Casa performance for these iconic models. Often overlooked in comparison to their bigger siblings, there are now some serious upgrades available. Next week sees the release of the Vega5 (5-speed) gearbox for all J Range, Lui, Vega and Cometa models. The Vega5 is plug & play on all 3-speed and 4-speed models.
The difference 5-speed boxes have made to large frame Lambrettas is profound, so a potential upgrade from 3 to 5 gears will transform even a completely stock small frame! Add the CP One35 cylinder kit too, and these scooters become something truly different. So to let that sink in, you can now convert a 50cc 3-speed Lui into a 15bhp, 5-speed ripper. The transformation and improved gear overlap is instantly apparent when comparing these two scenarios in the Visualiser.
The ratios of the Vega5 mean that if used in standard 75cc engines, the primary drive front sprockets would need to be smaller than standard (i.e. 13T on Lui , Vega and Cometa models). Casa Performance have now manufactured 11T and 12T for 4-speed casings and whilst they were at it, they also made 12T sprockets for 3-speed casings as well. This effectively means that smallframe Lambretta owners now have a huge, unprecedented choice of sprockets to choose from for both 3-speed and 4-speed engine casings (they use different drive side bearing and sprocket / sleeve set-ups) ranging from 11T through to 16T, for both non-cushdrive and cushdrive set-ups. Coupled with the Casa Performance ‘LunaMaster’ 5-plate clutches in 45T, 46T and 47T crown wheel options, this gives 18 primary ratio options to play with for that perfect setup. RLC have ensured they have top quality Iwis chains for all of these possible combinations, and have kindly provided this data for inclusion in the Visualiser.
Casa Performance has introduced a new 4-speed close ratio gearbox for Series 1, 2, 3 GP / DL or Serveta scooters. Ratios were chosen by Vittorio Tessera in order to provide a close ratio gearbox at a lower price point than the Cyclone 5-speed.
The gearbox was designed and developed specifically for the Casa Lambretta Racing Team and used during their victorious 2015 ESC Championship season.
The gearbox ratios are configured differently to most on the market. Generally close ratio boxes reduce the jump between the highest gears, which helps relatively older low-powered, gear-challenged engines pull higher speeds without dropping out of the power. The CASA gearbox has a very “long” 2nd gear (more like two and a half) and then a fairly normal 3rd and 4th. The result is likely to be a gearbox that is very useable in 2nd and 3rd whilst retaining a 4th that would still give a good top end – i.e. think like a twisty circuit with a long straight where more benefit is realised in the twisty section. This could also translate well to riding around town and city centres.
The Gori RV4S 4-Speed code ratio gearbox has now been added to the visualiser.
The Gori website details the thinking behind the ratios on this gearbox as well as some detail on the production process.
This sport gearbox was designed and developed by Gori Elaborazioni and entirely manufactured in Italy by Micozzi Ingranaggi [Macerata]. RV4S is the state of the art solution to enjoy maximum engine torque no matter what is the tuning configuration of your Lambretta. RV4S is made of a robust alloy of of nickel-chromium-molybdenum 18 nc 05 and it is specially treated with a process of carburizing and quenching. Gearwheels are at least as thick as the original ones. RV4S is a very precise and robust product at an affordable price.
RV4S was specifically designed to achieve the best possible performance ratio at any times and in any gear, thanks to the fact that torque is more prompt and available at higher revs.
First gear is rather elastic while the other gears are very tight to each other, which allows to ride uphill hairpins in first gear and then enjoy the very tight second gear for quicker output. When shifting, the decline of revolutions is very limited, thus allowing the best possible progression with no significant loss of power. As a matter of fact, our road tests confirmed that the best performance is obtained on uphill riding and on combined cycles.
RV4S can be fitted both on tuned and on standard Lambretta engines. Transmission is easily mountable and fits the standard selector (which doesn’t even need to be replaced). For lovers of technical values we will be glad to provide the graphs of some of our tests with different pinions with different number of teeth. Our applications show that the decline in the number of revs when shifting is very limited: percentages range between 22% and 18%.