ET3 130

[keuk]

Hi,

 

Here is my ET3 130 project, which has now only the stickers from an ET3.

It works  well on the road but there is still room for improvment, I hope you can help me.

The main idea is to keep and original look/noise. So a banana style exhaust is what I would like to keep.

On the road to the Rallye des Gones.

 

I have the following setup:

Polini Evo original timings, only bigger transfert ports, exhaust fitted to SIP road diameter

Casing machined, from an old racer engine

Polini intake manifold with SHB19 with polini airfilter

Mazzu crankshaft

PK 12v ignition with lightened PK flywheel (serie pro I guess ?), 17°

Ratio 2,76

4th short BGM 48 teeth

3.5 tires

 

I did a rotronic test last week end and get this before the hard disk crashed:

10,7 hp at 6700rpm 

12,3 N.m (1,254M.kg) at 5814rpm (only the last one is good, we forgot to calculate the losses related to the gearbox on the others).

There is a second peak after 8000 so I wonder if I could do something to optimise it.

On an standard engine Sip did this dyno:

7,7hp / 5612rpm

10,5N.m / 3640rpm

 

Is there any informations / threads / dynos with the sip road exhaust ? 

Thanks for your advices.

 

Greetings from France

Antoine

Bearbeitet 16. Juli 2018 von keuk

[BerntStein]

hmm. sure the exhaust channel isnt too wide for this ?

what timings and squish do you have now?

i had an et3 cylinder tuned and when the exhaust got to wide, it  lost power.

i dont think you need those 70% for 13 horses.

someday a 24 could replace this rather small carb if the rest is okay.

 

 

[keuk]

I haven't modified the wideness of the exhaust, original shape what like this, and already 70%

 

I will control the timings to see, for the squich I have 1,1mm. 

 

I would like to keep a 19mm for a good fuel consumption, it was around 4,3L/100km this week end,with a lot of 3/4 gear in backcountry. I could test a PHB19 or remove the Polini airfilter and put a bigger mainjet.

 

I have added the curves to compare with the original engine.

[rennvespe]

I would also dump the 19mm carb in favour of a 24mm or even bigger one. I have a fuel consumption of ~4L/100km when driving mostly part throttle between 80 and 100km/h with my 28mm OKO PWK on the old 133 Polini.

Maybe you also try and set the ignition to 18, 19 or 20° and look what happens.

 

Remove the flute of the exhaust on the dyno and look if the hp increase. If yes, you could make yourself a flute with bigger inner diameter for better flow and more HP on top of the RPM range.

 

Edit: You have a little flat spot in the climbing power area. I havent seen this before with this type of exhaust. Is your main jet set correctly or maybe a bit too rich?

Bearbeitet 17. Juli 2018 von rennvespe

[keuk]

The spark looks great, but the floor of the scoot is really greasy. I can try something, but when throtling at max during big distances the behaviour was ok. I can test few points less.

 

I will also test the mono reeds in the manifold.

 

And in a second step, I'll try a bigger carb to see the difference, I have a Koso28 with a 28mm intake.

[rennvespe]

With these type of exhausts (+Polini lefthand, etc.) you do not notice a too rich setting right away when driving, i have experienced.

Sprayback can be a sign of a too rich setting.

 

If everything is set up right, the engine should be able to produce around 12 to maybe 14HP with your current configiration i think....

[keuk]

Thanks for the advices, I will work on this points.

[keuk]

vor 23 Stunden schrieb rennvespe:

With these type of exhausts (+Polini lefthand, etc.) you do not notice a too rich setting right away when driving, i have experienced.

Sprayback can be a sign of a too rich setting.

 

If everything is set up right, the engine should be able to produce around 12 to maybe 14HP with your current configiration i think....

 

Have you ever tried the BGM PRO sport ? 

 

https://blog.scooter-center.com/fr/pot-dechappement-banane-de-malossi-pour-vespa-pv125-et3/?utm_source=newsletter&utm_medium=email&utm_content=MEHR+LESEN&utm_campaign=newsletter-classic-de

 

I wonder if the inner tube at the cylinder exist is bigger than the Sip road. 

[rennvespe]

No, unfortunately not.

 

[keuk]

Befindet sich die Xyger-Platte für die PK XL2-Kupplung noch? Es gibt das Modell DRT bei 10pollicci, aber mit den Versandkosten kostet es ein Vermögen.

[BerntStein]

i have one for you !

[keuk]

Dope! Danke !