RD Vespa Carburettor Idle Jet (SI 20.15 - 26.26D/H/E
The choice of idle jets primarily effects the lower to mid rev range. The jets are marked with two numbers, e.g. 55/160. Smaller the number larger the jet, and/or bigger the calculated ratio. With the adjustment of the smaller size leaner the scooter will run at moderate revs.
Comparison No. 0989204 02 (DELLORTO)