Modern Vespa

My friend has a 60’s vbb with a 150 motor in it. Has 8” wheels and a four speed. Problem is we cannot get it to start with the kick. It is almost like the flywheel only gets around once each time you kick it. The kick start lever seems to be the proper one but it doesn’t seem to have enough oomph to get her to start. She starts great pushing it and it runs good and strong. I would have no problem push starting it every time bus my friend is not able to push start it often. Any ideas? Could it just be something as easy as weak spark?

How does the clutch feel ? If the cable is on the tight side it could be keeping the clutch from full engaging. Do you notice clutch chatter when taking off from a dead stop or slippage under hard acceleration ?

The clutch is performing as it should. No slipping or chatter. The flywheel turns immediately when you kick itover but it doesn’t seem to get enough momentum to start

I just checked a VBB and one stroke of the kick 'pedal' equals one and one half revolutions of the flywheel so it's not really going to spin it around much working against any real compression. Good compression, a good plug, correct timing, a strong spark, and proper jetting should combine to fire it off even on one revolution.