Test bench runs, diagrams, experiences and results

Polini has redeveloped the proven Polini banana and given it a new look. What the new banana or, according to the new Polini nomenclature, the "original" exhaust can do; I took a look for you.

From a purely visual point of view, the new original banana differs significantly from the design of the older vintages. The body has become thicker in terms of material and shaped differently. The plug connection on the manifold looks much more binding and the position for hanging the exhaust spring moves to a more accessible area.

Polini offers the exhaust systems for the PK and V50/PV engine cases. So far, the bananas for the PK models have always been provided with a clear flattening in the area of ​​the manifold. The new original from Polini only shows a different course of the manifold, without flattening.

Another significant improvement is the bracket that connects the muffler and engine case. Once the base plate of the bracket is mounted on the engine housing, the muffler can be easily mounted and dismounted using two M8 screws.

In the previous model of the banana, this principle was already used in racing, for example in class 5 of the ESC, to enable faster tire changes, but individual initiative was required when creating the bracket.

In general, Polini seems to have taken some experience from the racing circuit with him on the new banana. The new Polini banana is also directly suitable for the tire dimension 3.50-10, which is used almost exclusively in the racing series. The usual tires of the Smallframes with 3.00-10 therefore of course still fits.

I put the new original banana on my K5 for you and did a few tests.

The assembly went well. No bending, pressing or worse interventions are necessary to position the exhaust properly on the scooter.

The slotted holes in the bracket provide significant leeway for adjusting the system to prevent contact with the tire and brake drum.

Polini oddly states that the length of the shock absorber should be determined before installing the exhaust system. 

The tested minimum size of the shock absorbers, i.e. when the shock absorber is compressed to the stop, should prevent the exhaust system from coming into contact with the frame.

Owners of the bgm Pro rear shock absorbers can feel safe here. The dampers have the required minimum size and in the case of the Sport series, the height of the damper can even be adjusted further.

But now to the result on the test bench.

I would like to say in advance that every engine behaves differently and the differences can be more or less noticeable depending on the processing. It has been shown that the difference is clearer with less powerful or unprocessed engines than with concepts that are a little more sophisticated.
Here the new Polini Banana takes place on a motor that
Class 5 ESC rules.

The carburetor in this case is a PHBL 24, intake manifold Polini membrane, cylinder Polini 133 Racing cast iron. Crankshaft Mazzucchelli Racing.
The motor housing is machined for the diaphragm inlet and the transfer channels in the motor housing are adapted to the cylinder. The cylinder and the intake manifold remain unmachined.

In racing trim, my 508 tends to be in the 15hp range, depending on how I feel on the day. Therefore, the first run is first of all to see whether the engine is still in the best of health.

As expected, the 508 delivers 14.9 hp at 7300 rpm after warming up.

So everything is healthy and the new Polini original exhaust is fitted for comparison.

Even on the test bench, the significantly higher starting torque is noticeable when warming up. Polini did a good job here. What feels different on the dyno is also reflected in the graph.

At a slightly lower speed of 6660 rpm, the new 2022 banana with 15.5 hp increases by 0.6 hp compared to the older design. The maximum torque, increased by 0.9Nm, is already at 5200rpm.

In a direct comparison of the two curves, the character of the new 22 banana can be seen. Earlier - more.

Up to approx. 7200 rpm, the 22 banana has the edge in comparison. Exactly the area in which an engine with this power is most often moved on the road. From about 7300 rpm the older banana looks a little better and shows a little more desire for higher speeds.

The configuration of the carburetor was not changed between the two runs. My assumption here would be that with a subtly smaller main jet and needle/mixing tube combination, the 22 banana can still gain a bit in the higher rpm range.

But I'll leave that to your play instinct to find out.

My personal opinion:

Polini has done a good job developing a very nice everyday rideable exhaust with some good improvements. The easier to reach position of the spring, the more solid plug connection and the easily adjustable bracket are positive. I see the usability on larger tires as a further plus. In terms of noise, the new banana is a bit duller than the previous model.

In the video you can get more impressions of the new Polini Banana

Part 5 for stage 4

Fortunately, as with so many things in life, everyone has their preferences...
More RPM and more peak power or more torque at low RPM.

That's why in today's part I'm looking for more... But not top performance, but for speed range and torque. The "tractor engine" is sought.

In part 4 with stage 3, I looked in the direction of the higher control angle by raising the cylinder and making a small adjustment to the exhaust. If I were now to increase the exhaust further in order to perhaps achieve higher peak performance and speed, the way would be backwards; to try the cylinder with more blowdown at lower control angles installed.

So today I lower the cylinder. Overall, this results in lower control angles, but the pre-release increases slightly. The smaller transfer angle should allow the cylinder to produce a little more torque at low rpm.

The spacer on the cylinder head was changed from 1mm to 3mm compared to the third construction stage. At the cylinder base, the 2mm spacer leaves the field and the cylinder is only supported by a normal 0.3mm thick gasket. The squeezing edge remains at 1.3mm, as with the other construction stages.

In the following graphs are the current curves of construction stage 4 RED to see. The curves from the previous stage three appear in BLUE.

Elron is the first to show what he thinks of the change.

As can be expected, the absolute top performance drops slightly, but the maximum performance and torque shift in the direction of lower speeds. The torque increases slightly and feeds the range between 5100 and 7000 rpm.

The Polini box, which is more intended for engines with less transfer time, is placed next on the exhaust port.

At first glance, the curves may seem sobering. On closer inspection, the Polini Box turns out to be a real torque animal. At the end of this series of tests, it will rank second in terms of torque with 37.4Nm. The graph already passes the 4700 hp mark at 20 rpm. The maximum power shifts by an impressive 1000 rpm in the direction of a lower speed, culminating at 6400 rpm. The maximum torque pulls at the rear wheel at 6000 rpm. An engine constructed in this way is just begging for a long gearbox.

This allows the M244 to move over the asphalt with extreme shift laziness. Jack off the stand, shift into gear 4 and just pull the cable. Don't worry, it will be quick...


The aged all-rounder in the field.

The JL left arm puts its torque in the range between 5000 and 7000 rpm and thus offers more drivability. Although the peak power falls by one hp, the JL can still offer very good drivability in the field of resonance exhaust systems.

New Line

The handwork from the north is also responding to the adjustments as expected. Already at 5000rpm, 20 horses are ready to move significantly. Full torque is available at 6100 rpm. Although it pushes the absolute top performance down a bit and the Newline gives up 2 horses in favor of the early torque, it is happy to take the larger pre-release in order to go over 10.000 rpm and maintain it there with over 20 hp.
The Newline behaves here almost like a box exhaust system, seasoned with a significant torque kick.

Posch Nessi

The sea monster ducks its head slightly due to the reduced steering angles. But that's not bad at all. As with the Newline, the rev range shifts slightly towards early revs and develops more torque in the process. At 5200 rpm the curve already exceeds the 20 hp mark. The slightly increased pre-let helps the Nessi to a wider speed range.

Posch Racing Resi

The lush Resi handles the steering angle that is unsuitable for you amazingly well. Although it also loses peak performance, it gives an idea of ​​the bandwidth that can be possible with the appropriate control angles and more forward airflow. With a speed range of almost 4100 rpm, it is in the top league here.


The Lakers, made for a lot more alert, don't like the slack head angles that much. The exhaust craves for larger time cross sections. The speed range shifts to lower speeds as expected, but the low time cross sections are not the right playing field for the Lakers. But his chance will come with the following expansion stages...


Here again all maximum values ​​in the overview

Scooter Center Open day 2021

Scooter Center Open Day 2021 con casi 1.500 Vespistas y Lambretteros

Scooter Center Open Day 2021 – 1500 Vespa & Lambretta Scooterists

Un day para los amigos, donde los amigos 

Este no es uno de esos eslogans vacíos de Marketing, si no ¡la esencia de nuestro Open Day!
Nosotros mismos vivimos la cultura de andar en scooter e intentamos permanecer en contacto con la escena y good parte de esta, son las scooters Mismas, for the intense lives and hearts accompanied by this movement of more than 30 years.

Mejor aún fue Finderarnos finalmente de nuevo con gente normal y habenrar amigos que están igual de locos por las scooter como nosotros.

y por ello les queremos dar las gracias! Gracias que se tomaron el día para hacer de el, una experiencia inolvidable.

Open Day -2021 – That Scooter Center Team says thank you!

¡Finally gente normal!

¡La escena estuvo a todo dar!

Sabemos todos lo que fueron estos los últimos meses con las restricciones y casi ningún evento, por lo que sabíamos que muchos de ustedes estaban esperando el momento de reencontrarse, pues nosotros mismos estábamos igual, por lo de que tuvimos el que higiene, duplicando esfuerzos. Incluso en las bebidas y comida, y aún así, ¡hizo falta! por lo que tuvimos que hacer pedidos extra… ¡varias veces!




Nuestro banco de pruebas, donde estaban Alex y Uwe, también funcionó muy bien; with the excepción de un breve descanso, ¡hubo una pruebas tras otras!


Alex and Uwe with an ACMA tubular handlebar on the dynamometer

Donaciones para los niños con cáncer con un monto de 6.179,80 euros

Markus Mayer is here this year with the end of the Gentleman Giro 2021 and his patches, buttons and buttons together with several galletas, posters and keys for cambiados por donaciones, alcanzando la suma de 1.179,80 Euros!

Las institutions para niños con cáncer se alegran de vuestra insaciable sed y hambre pues hemos redondeado la totalidad de los ingresos de nuestra gastronomía a 5.000 euros, por lo tanto, podemos transferir 6.179,80 euros a la Fundación Alemana versus el Cáncer Infantil. ¡Estamos muy contentos y orgullosos de ustedes!


Markus Gentleman Giro donation

International exhibitors and visitors

All lado de nuestro mercado de partes y repuestos, que este año fue gigante, nos acompañaron también stands de todos los tamaños y nacionalidades, desde Alemania, cómo también de Italia, el Tirol del sur y la Toscana. Muchas gracias por venir con ¡los asombrosos productos que fabrican!

M&R Maletas especialmente diseñadas para Vespa, hechas a mano (I)
Mercado de parts and Vespas de Segunda Garage Rosso (I)
The Mercado de repuestos de Bernd
The mercado de repuestos de Hubert D.
The mercado de repuestos de Herbert S.
El mercado de repuestos de Milan design writer
El mercado de repuestos de acki and mika
Markus Mayer Gentleman Giro
évoRetrofit electric kits for Vespas clásicas
Crazy Monkey Development & Savage Scooters
Tom Super Lui (I)
McCloudt's Originals
The Mercado de Repuestos de Kölle
The DeZonk repuesto store
Vespa scooter paradise - Colonia
Christian S. Rollershop Zirris Scoot-Devils

Èvo Retrofit por ejemplo tuvo más de 60 pruebas de manejo con sus testbikes electrónicas, luego les mostraremos de esto un poco más pues Maryzabel y Heiko tuvieron la oportunidad de manejarlas y hacerles una entrevista de como electradas funcas funcas funcas.

¡Espera pronto el video!

New visitates, trajeron una variada muestra de Vespas, Lambrettas, Vespas más modernas como la GTS, Primavera, etc. ¡simplemente genial!


Podemos mencionar clubs y visitantes de:

  • Austria
  • Luxembourg
  • Belgium
  • Netherlands

Saludamos a los siguientes clubs que vimos:

  • Viennese rogue
  • Flatliners
  • Filthy & Sly
  • Toast riders
  • Minus screwdriver
  • Vespa Club Roude Leiw Letzebuerg
  • Vespen Nest Düren
  • Vespa Club RheinSchalter Cologne
  • Tin vespa Vespa joy
  • Vespa Club Mainz
  • Kulturbanausen Roller Club Rhineland
  • Vespa cowboys
  • Scoot Devils
  • Blues SC Munich
  • Vespa Club Bogota

De seguro nos hizo falta alguien, si es así, por favor comments!


Nuestro Highlight personal

Aparte de las caras familiares y amigos, nos alegramos por ver una en especial, los amigos de ROLLERSHOP - Zirri-Smallframesee El sueño de cada jóven alemán!

Acá también tenemos una super historia que contar y qué tu no te puedes perder.

Pronto more info acá en the blog.

Heiko scooter shop Zirri


Photos Scooter Center Open day 2021


Lambretta exhaust test Big Box Reso racing exhaust

Test of the escape from resonance and the prototipo Big Box para Lambretta

Una test with the escape para Lambretta: el new and próximo Lambretta Big Box está actualmente en production, desafortunadamente, aún no se tiene una fecha de entrega determinada. Exhaust test on the Scooter Center Performance test bench

The escape systems for Lambretta, can be checked

Antes de delivery the muestra final in España, pusimos la new box a prueba. Other prototype of new Amiga Chalky de Replay Scooters y JPP for direct payments to the bank of Pruebas:

  • bgm PRO BigBox Proto
  • JPP box prototype

Los siguientes escapes de resonancia compitieron versus los box:

  • the TSR Evo,
  • el JL3 y
  • in MB3

Y los tres escapes Reso les fue most de lo que esperábamos! The Lambretta exhaust systems

El engine Lambretta

The motor de prueba fue construido de la siguiente manera:

Resultado y conclusion de la prueba

Es agradable y claro ver lo bien que los box lideran desde el principio, no sólo en power, sino también con el torsion In comparison with the “escapes de carrera / racing”.

Eso hace que los box de bgm PRO sean tan agradables de conducir. Siempre hay suficiente potencia available, sin tener que luchar con problemas de engranaje o tener que girar el acelerador como un loco para que avance.

Los moderados valores de los motores con las Box de bgm son una ventaja adicional, además de la óptica original, el agradable ruido de fondo. Otra característica sobresaliente es el sistema de montaje con posibilidades de ajuste, tanto en dirección horizontal como vertical, esto permite compensar las tolerancias y especialmente los espaciadores utilizados para diferentes golpes y longitudes de biela.

Diagrams of rendimiento de las pruebas con los escape de Lambretta

Aquí puedeshabenrar los diagramas de rendimiento en formato PDF: