carburazione 28PHBH Malossi MHR 132 + MRT al cilindro

[sven2242]

Buongiorno,

consiglio carburazione per nuovo motore

approssimativamente da dove iniziare prima della regolazione

Carburazione :getti Max ? 🧐

per 28PHBH al cilindro collettore lamellare MRT

 

motore :

Malossi 132 MHR alluminio squish 1mm

collettore lamellare MRT al cilindro

Accensione Polini variabile

27/69 FRT/BFA

marmitta Dexter Classic Box 32

Carter SIP Evo2

frizione FB24

[sven2242]

[McKenzie]

Vedi se ti trovi bene con il filtro ed il rapido (molti non piace).

A quanto hai settato l'anticipo?

Hai un contagiri?

Questo mi sa che è un bel motorello furbo, che gomma ci monti? 

[sven2242]

I want a Vespa that looks original/classic

so : 

Sip tubeless wheels + Sava MC12

anticipo a 25/24 gradi  (motor-art-retro tells me it’s best for my configuration)

no contagiri 

😉

[Turbo99]

Carburazione per iniziare phbh28:

min 55

x2

av266

max 130.

 @Diegof12 lui può aiutarti sulla carburazione visto che ha avuto un motore simile.

[Diegof12]

Eccomi

minimo 45

polve AV268

max 125

spillo x11 2ª tacca dall’alto

 

Ma avevo un’espansione, quindi credo che da qua dovrai togliere qualcosa di polverizzatore e getto massimo

[sven2242]

Grazie mille @Turbo99 @Diegof12

La mia carburazione :

max 122

minimo 55

spillo x2  2ª tacca dall’alto

polve AV264

 

il motore non giri

 

troppo grasso 

 

Metterò Max 120 /118

 

Actually fueling is too rich,

because the engine doesn’t want to go revving.

only if a close the fuel screw it’s better.

So i will try jetting with a 120 or a 118 I think.

😉

doesn’t if a need to change something else !

 

 

[Diegof12]

5 ore fa, sven2242 ha scritto:

Grazie mille @Turbo99 @Diegof12

La mia carburazione :

 

max 122

minimo 55

spillo x2  2ª tacca dall’alto

polve AV264

 

il motore non giri

 

troppo grasso 

 

Metterò Max 120 /118

 

Actually fueling is too rich,

because the engine doesn’t want to go revving.

only if a close the fuel screw it’s better.

So i will try jetting with a 120 or a 118 I think.

😉

doesn’t if a need to change something else !

 

 

You can try 5 point step with big jets. 2 points sometimes is not enjoyable.

put on a 115 and try again, maybe this exhaust wants a maximum jet not too big, i suppose…

[sven2242]

Il 18/3/2024 at 00:53, Diegof12 ha scritto:

You can try 5 point step with big jets. 2 points sometimes is not enjoyable.

put on a 115 and try again, maybe this exhaust wants a maximum jet not too big, i suppose…

 

Test ride today !!!

configurazione Min 55 / Max 115

per regulare la vite della carburazione

la regolazione per farlo girare bene è di solo 1/2 (mezzo giro di vite) !

e non gira molto bene…

 

a un semaforo rosso decido di togliere il filtro dell’aria (ram air filter) = subito meglio !!!

 

Devo cambiare Min ???

55=> 52 o direttamente 50

Vorrei rimettere il filtro per sicurezza

 

Grazie per il vostro aiuto e consigli

Eric 🇫🇷

[Diegof12]

You can directly try the 50 jet. Ram air filter is not good, nobody use it anymore. You have to isolate the hole around the intake collector, maybe with a driveshaft boot and with a malossi sponge on the floor, you can find some examples in this forum.

Is possible that after remouving the ram air filter you have to put on a bigger maximum jet.

I hope to have written the right way in english 😁

[sven2242]

6 hours ago, Diegof12 said:

You can directly try the 50 jet. Ram air filter is not good, nobody use it anymore. You have to isolate the hole around the intake collector, maybe with a driveshaft boot and with a malossi sponge on the floor, you can find some examples in this forum.

Is possible that after remouving the ram air filter you have to put on a bigger maximum jet.

I hope to have written the right way in english 😁

Perfetto !!!  😉

[solovalvola]

Ramair filter is not so good...

just isolate the the area around the carburator as told you above and you'll be fine!

 

I noticed you have quite a long rubber connection between carburator and intake manifold....You could easily shorten it at least 2-3cm (also by cutting the intake manifold, if necessary).

 

The inner clamp can be positioned past the rubber boot and tightened from the left rear side, just above the tyre. This will make the intake work much better!

 

As anticipated by Diegof12, after those adjustments, you might need to enrich the mixture again in terms of main jet. For your info, on the same carburator coupled on a 100 VMC with expansion exhaust, I use a main jet of 115, idle jet 56, atomizer AV266, needle X2.

 

Last but not least, I understand you want to keep the vespa's look as original as possible, but using this kind of exhaust on such a performing engine is a bit of nonsense.

Ciauz

[sven2242]

9 hours ago, solovalvola said:

Ramair filter is not so good...

just isolate the the area around the carburator as told you above and you'll be fine!

 

I noticed you have quite a long rubber connection between carburator and intake manifold....You could easily shorten it at least 2-3cm (also by cutting the intake manifold, if necessary).

 

The inner clamp can be positioned past the rubber boot and tightened from the left rear side, just above the tyre. This will make the intake work much better!

 

As anticipated by Diegof12, after those adjustments, you might need to enrich the mixture again in terms of main jet. For your info, on the same carburator coupled on a 100 VMC with expansion exhaust, I use a main jet of 115, idle jet 56, atomizer AV266, needle X2.

 

Last but not least, I understand you want to keep the vespa's look as original as possible, but using this kind of exhaust on such a performing engine is a bit of nonsense.

Ciauz

Thanks you so much for your advice 😉

i will cut the rubber connection and make those littles modifications 👍

 

for the exhaust, yes I know that a Raven or VMC Evo Racer will be lot better.

But if I put that sort of exhaust on my Vespa, it’s a lot « eye catching » and policemen 👮🏻‍♂️ will look a little more id there is other’s modifications… 🧐🫣

 

i put the Dexter Classic box 32mm because the noise is not too much and it’s has little more performance than a Proma or a classic Polini. 
But I know, it’s not « espansione » 😇

 

if I saw an « espansione » that OK for Vespa with the « big box glove Pré-1976 » and not too noisy, maybe I will test for the « fun » ! 🤩 

[sven2242]

And also I have I small problem :

Vespa Primavera 1975 (pre 1976 = cassettino è piu profondo…☹️)

[sven2242]

Hello

i cut 1 cm of the rubber between the carb and the manifold 😉

i also have the Polini airbox (not a real filter)

maybe I can try it ? (it’s the good size fitting for my carburetor 60mm fitting size) 

 

i don’t know if this airbox is good or not ???

[Diegof12]

I don’t like this airbox, on smallframe i never use a filter or airbox. The rubber collector has to be like the carburator is one piece with the intake collector, because chainging sections is very bad. It can cause a wrong feeling of fueling due to fuel accumulation in the bigger area

[sven2242]

On 4/4/2024 at 2:18 PM, Diegof12 said:

I don’t like this airbox, on smallframe i never use a filter or airbox. The rubber collector has to be like the carburator is one piece with the intake collector, because chainging sections is very bad. It can cause a wrong feeling of fueling due to fuel accumulation in the bigger area

After 15/20min ridding, the Vespa is not running good.

The engine cut off/stop if I drive at low speed or at the same speed if running slowly.

if the engine stop/cut off, I have to make 3/4 kicks the start and make few hard accelerations, if not = it cut off again.

 

i think that if the engine is hot, it need less fuel.

i actually have a : min 50 / max 118

i will change for a : min 45 / max 122

 

maybe I will end with the same settings than you Diego 😉

 

here is a phot of the spark plug after 150kms of « rodaggio »
spark plug Denso IW27 that was with the Malossi 132 MHR

Oil mix is 3% Bardhal KTS synthetic 

Edited May 9, 2024 by sven2242

[McKenzie]

Try also an AV266 with same setting