MDM Shorty for 102cc Polini

[pk_damiano_4hp]

Hi Guys,

 

I wanted to let you know about a product that I executed the design.

 

It is a muffler for small-frame which also mounts in the Vespa HP without removing the battery or the spare wheel.

I could test it on the dyno with excellent results, also making comparisons with Exhaust Polini Banana and Shaft site.

 

Sito Shaft 10,41cv a 8475gir./min.;
Polini Banana 9,47cv a 9303gir./min.;
MDM Shorty 13,79cv a 8975gir./min..
 

hope you like it

 

 
 

 

https://www.facebook.com/gianluca.marri/videos/10206708168283170/

[lokalpatriot]

Could you please say something about the time areas of the cylinder and mounted parts like crank,carb ...

I am very interested in new parts for our smallest engines!

[pk_damiano_4hp]

vor 11 Stunden schrieb lokalpatriot:

Could you please say something about the time areas of the cylinder and mounted parts like crank,carb ...

I am very interested in new parts for our smallest engines!

The engine in question was made on the basis of crankcase PK first series (2 holes), mounts a 102cc Polini cylinder with the exhaust slightly less than 180 °, reed valve Polini manifold with carburetor SHBC 19mm, standard crankshaft adapted to reed valve, 26/69 primary and standard gearbox.

[lukulus]

Why not picture the small frame exhaust, but the Px ??

[Brosi]

vor 50 Minuten schrieb lukulus:

Why not picture the small frame exhaust, but the Px ??

 

Das ist doch der SF Auspuff... oder was meinst du?

[remdabam]

righthand=sexy!

[pk_damiano_4hp]

Tests are continuing:

After yesterday dyno, we decided to do some modification to shorty prototype, modify the calibration of the bench and also try a new type muffler the Proma (with increased manifold) and MDM Easy (very appreciated on stroke 43mm engigne).
In the graphs, you can appreciate the power difference, being equal all parameters among the tested exhaust, I remember being:

 

- The Sito Shaft;
- The Polini "Banana";
- The Proma with increased manifold;
- The MDM Shorty;
- The MDM Easy.

 

The engine was not changed.

 

The results I differ from those posted yesterday because today we managed to find a better setting of the parameters of the bench, however, remember that the data obtained are only for comparative purposes since the dealer calibration is not final.

 

The comparison highlighted the excellent performance of the last born is compared to aftermarket mufflers from more than decent performance to both the MDM muffler best-selling ever.

with the Sito the engine had 11,58hp to 6256gir./min .;
with the Polini the engine had 9,96hp to 7938gir./min .;
with the Proma the engine had to 13,10hp 7502gir./min .;
with the MDM Shorty the engine had 14,57hp to 6499gir./min .;
with the MDM Easy the engine had to 15,22hp 7099gir./min ..

 

https://www.facebook.com/gianluca.marri/videos/10206722013069281/

 

 

[lukulus]

vor 11 Stunden schrieb Brosi:

 

Das ist doch der SF Auspuff... oder was meinst du?

 

 

sorry , zuwenig geschaut...

schon lange keinen lefthänd mehr gesehen für small

[lokalpatriot]

Lefthand? das andere Links!

[lukulus]

uff..  ich muss mehr schlafen...

[momo]

Same Engine but max power close to 3000 revs earlyer??? seems the calibration went wrong!?