A contact-break ignition system is prone to faults, only suitable for tuning to a limited extent, and always poses a risk on long journeys. For this reason, it is often replaced with an electronic ignition system. Until now, fans of the Vespa 125 VNB/GT/GTR//Super/TS/150 VBA/VBB/VGLA/B/GL/Sprint/V/Super had no choice but to fit a BAJAJ ignition system of questionable quality or a more expensive alternative. At the suggestion of STOFFI’s Garage, SIP has addressed this problem.
The solution is a fusion of two crankshaft types. The basis is the classic Sprint Crankshaft with the original Bearing and shaft seal seat. This is combined by MAZZUCCHELLI from the factory on the fan wheel side with a revised Cone of the modern PX Shaft. The clutch side remains unchanged.
With this SIP Crankshaft it is possible to use the proven and inexpensive electric Ignition of the PX on these oldies. The Oil Seals and Bearings remain original Sprint.
Due to the housing tolerances, clearance or ignition problems may occur when fitting the Ignition . To prevent the Wire from being crushed or the Base Plate having to be modified, we recommend installing a Spacer under the Stator Plate.
Conclusion: Perfect solution for conversion to electric Ignition
Crankshaft / 57mm stroke / 20/25mm / M12
Crankshaft for conversion to PX Ignition with Ø 95mm Lima cheek, Ø 97.9mm rotary valve cheek, shaft seal seat 20mm, bearing seat 25mm, blunt/thick Cone of the PX with M12mm thread, including connecting rod bearing
SIP-TiPP: Don't forget new Woodruff Key, M12 pole nut and Lock Washer. Order a PX Lusso Stator Plate and PX Flywheel such as SIP Touren, PX200 or even a VAPE ignition. The Spacer for the ignition base plate # 50011300 is also useful.
Robert Zinnöcker "Zini". STOFFI-SIP Racing Team:
"We've been waiting for this for years. At last, the old sprint engines can be converted to electric Ignition cheaply and reliably. Perfect."
The timings stated above were determined viewing in the direction of the clutch side. That means: "138°/6° after TDC: Inlet timing begins 6° after TDC and stays open for 138°.
Please note that the angular degrees given here are approximate values, as the crankshafts are reworked by hand.
