Polini 210 on our P4 dyno

Today we had a real beauty on our Dyno. A Vespa Rally 200.

The aim of this project was to get a tractor torque engine for daily driving.

Base was a Vespa PX200 Motor, the rotary valve in the housing has been expanded for more discreet inlet angle before TDC. Crankshaft is a genuine PX200 crank with 57mm stroke.

The new 210 Polini is filled by a SI26 carb with Polini induction funnel.

Because of the Polini induction funnel the available torque in the lower rev range stands out very clearly. The same engine with a Malossi cylinder without the Polini funnel is “missing” almost 4Nm in the same rpm range!

The alloy Polini is supported by a SIP Road exhaust.

From idle speed the engine has proper torque and power.

15hp and 23Nm from 4500 U/min speak for themselves.

With a taller Primary gear the torque can be stretched and relatively high speeds can be achieved at low rpm.

Nice set-up!