A recent addition to the tuning market is this exotic speciality from India. Produced under license by LML as the NV series, it is outwardly identical in shape and design to the original PIAGGIO PX80-150 motor. The secret to these crankcases though is the inconspicuously located reed valve induction assembly.
The inlet itself is spread over both crankcase halves. This enables the incoming mixture to flow in straight over the crankshaft so allowing a more direct and effective gasflow underneath the piston, with no corners or edges. What used to be only achievable with much welding, skimming, machining and twisted cases ending in the bin is now factory produced, so avoiding risk of failure. The large transfers machined into the crankcases match, with very slight modification, the transfer ports of most tuning cylinders from 166-177cc.
The advantages summarised:
- reed valve possible in combination with the DELLORTO SI carb. 20/24/26mm
- extremely inconspicuous reed valve upgrade
- cleaner exhaust emissions and higher fuel economy
- more power available due to the reed valve system
- a good basis for tuning projects including the larger 30-34mm DELLORTO PHB/VHSB carbs.
The internal components of your existing motor can all still be used with no problem. All PX parts fit in these crankcases. A high primary compression (HPC) or full circle crankshaft is ideal in combination with this reed valved carburettor inlet.
Conclusion: Ideal basis for all 166-177cc motor tuning projects.
SIP-TIP: Do not forget to order fresh gear box oil, oil seals, gaskets and a reed valve assembly when ordering this motor. MMW have manifold adaptors available for the use of the larger carburettor models (30-36mm) .
SIP community user “kb2061978” on Art.-No. 40311000: “I have been riding around using the LML crankcases in combination with a POLINI 177cc, a 24mm SI carb. and a full circle crankshaft since 2006. Fact is, this engine does the business. It allows a perfect setup to be achieved. The transfers are big enough, just had to be matched up for an ideal fit, so no plug-and-play exactly... I'd always use this setup if I had to build another motor. In the end, it's the best option if you want to run a SI carb. on a reed valve manifold.”
SIP community user „pcirinci“: „Very nice quality. It has larger cylinder porting than a standard caseing, but the ports look better matched to the Malossi cylinder. On the Polini the ports are offset by about 5mm.“