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Flowed Crankshaft SERIE PRO by Worb5 for Vespa PK125 ETS/N/XL/XL2
In stock
Delivery time 1-3 workdays
Part no.: 46090000
Including VAT Free shipping
1,95kg / Piece
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Flowed Crankshaft SERIE PRO by Worb5

for Vespa PK125 ETS/​N/​XL/​XL2

  • reed valve
  • stroke 51,0mm
  • conrod 97,0mm
  • Sport - con rod
  • cone 24/25mm, M12
  • fine balanced
TUNING SPORT - high-performance
In stock
Delivery time 1-3 workdays
5 ratings
Including VAT Free shipping
1,95kg / Piece

Product description

The Flowed crankshafts belong to the Low Primary Compression (LPC) crankshaft type which originally leave the factory as MAZZUCHELLI or TAMENI full circle crankshafts. The SERIE PRO range of crankshafts are produced by the German tuners WORB5.


These flowed crankshafts are specially machined to optimise gas flow in the pre-combustion area of the crankcase. The crankwebs have been modified to enable the fuel mixture free flow, unhindered from the turbulence created by the crankshaft. This design also allows a higher volume of fuel mixture to enter the crankcase and so enable a higher compression of gases above the piston in the combustion area. This combination facilitates a wider power band and consequently higher maximum power. Flowed crankshafts are only suitable for use in reed valve motors. The original Vespa disc valve mechanism provided by the clutch side crank web is no longer possible with this heavily altered crankshaft.


Conclusion: Perfect for reed valve motors. Larger, gas flowed ports and inlets are finally possible!


SIP community user „rigger“, England:

“Flowed/mapped for your performance. Gas/oil decreased resistance. Equals more power on demand. Throttle response is even better.”


Flowed crankshaft / stroke 51mm / connecting rod 97mm / 24/25mm, M12

Flowed crankshaft with Ø 82mm crankweb (flywheel side), Ø 87mm crankweb (disc valve side), 97mm connecting rod with 2 additional lubrication bores, oil seal housing 24mm, bearing housing 25mm, stump cone with M12mm thread, incl. connecting rod bearing


SIP-TIP: New bearings, oil seals and keys are a must. Same goes for sealing kit, clutch-, and flywheel nuts. You?ll also need a POLINI, MALOSSI or HHP reed valve manifold.

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Get inspired. This product is included in the following public notepads:
Notepad name User Date Article Note
111 SHOTAK October 3, 2022 29 View notepad
Motorrevision PK125 Dez. 22 ChristianG6332 January 9, 2023 19 View notepad
01082021 carrozzeria January 6, 2021 7 View notepad
Roth FlorianB7588 December 28, 2020 10 View notepad

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File name File type Description File size
Kurbelwelle-1 Technik Kurbelwelle 0,72 MB Download
Crankshaft technology Crankshaft technology 5,54 MB Download
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