Hi!

I have a Polini221 engine that rides very smooth. -never had so little vibrations in a Vespa engine...

But that is only as long I don't push it over 7000rpm...

-then it starts to vibrate heavily...

I'm suspecting that the pick-up isn't all good, and can't deliver proper sparks above 7k rpm.

-does that makes sence?

 

 

Setup;

PX200 casing matched to sylinder

60mm crank (unknown brand, bought here on GSF)

SI24/24 autolube with nd3,33 and hd128

Standard ignition on 19"

Polini box exhaust.

 

 

Rgrds
Ø

Bearbeitet 7. Juni 20197 Jr. von Svint1

Put in a bigger HD

Carb is overworked?

Put in a bigger HD
Carb is overworked?

Tried 135, and same vibrations...


Sent from my iPhone using Tapatalk

Are the vibrations gone if you come in higher revs?

Are the vibrations gone if you come in higher revs?

Haven’t tried to push it to far above 7k, as it vinrates so much.


Sent from my iPhone using Tapatalk

I think it comes from the Polini Box. I had this, too. With an other Polini Box the vibrations were gone.

1 hour ago, shamane said:

I think it comes from the Polini Box. I had this, too. With an other Polini Box the vibrations were gone.

Ok, thanks!

 

Very usefull information!

-I have been thinking of that myself, but wasn't sure...

I might try with a SIP Road to check....

I ve tested the Polini Box since 600km with a bunch of carb. Modifikations but I still have these vibrations. 

 

There could be a relation between the attachment oft the Box and the cylinder, i guess.  I´ll try to put on the viton attachment, to solve this Problem.