Modern Vespa

Just to close this thread out, I figured out why my kickstart lever wasn't fully returning. It was the kickstart return spring. It was defective, the bend that hooks into the notch on the quadrant was too far forward, and so the quadrant had very little spring tension on it at the top of its travel. The defect was noticeable when comparing the spring to a couple of genuine Piaggio springs.

The spring issue was compounded by a quadrant that had the notch in the cup slightly off as well.

With a "made in Italy" quadrant and Piaggio spring installed, along with some massive gorilla hands, the kickstart assembly now returns smartly to the top of the stroke

In retrospect, I should have noticed the spring defect, as it was really easy to seat the spring end in the quadrant notch. I suspect the spring was from India.





My first time building a motor up from scratch, cases on up (p210) is driving my crazy. Everything's great, except the kickstart. I've had the motor apart now 3 times trying to solve the problem. Thoughts appreciated.

Problem: the kickstart quadrant returns smartly all the way to the rubber buffer when the cases are split, and the spring firmly holds the quadrant where it is supposed to be. But when the cases are joined and bolted down the kickstart quadrant has an inch or so of slack/play at the top of the travel. In the installed engine, rebound momentum from a good kick will return the lever all the way back up to the rubber buffer, but the lever will easily fall/go down an inch or two, and when I push it with my hand, I can clearly feel "slack" over that initial rotation. The problem is that when I hit a bump riding around town, the kickstart lever goes down, stays down, and just begins to engage the kickstart gear, which then makes a persistent grinding noise until I use my foot to lift the kickstart lever back into the "top" position.

Attempted solutions: (1) Bought new kickstart quadrant in case original (new) one was bent. Made no difference; (2) tried two different kickstart gears (same ones I use in my Stella motor), made no difference; (3) reinstalled the quadrant return spring; it seems installed correctly, not broken, etc; (4) thought that the internal plastic oil-splash insert thingamabob might be interfering with the quadrant's return, and so ground the plastic down so it was flush with the clutch-side case. Made no difference. (5) inspected rubber buffers; they look to be installed correctly

Other observations: On each re-assembly I have had a devil of a time getting the cases to go together, and have had to massage the kickstart lever to get the quadrant gear to allow the cases to be drawn to together.

Speculative worry: I didn't measure it last time the cases were split, but maybe I installed an "old" style input shaft in the xmas tree, with the 11.5mm shaft on the flywheel end? https://modernvespa.com/forum/post2558860#2558860

Would that make a difference? Could the "wrong" spindle/xmas tree set-up cause a kickstart problem?

The drive gears, drive shaft, and shifter are EFL; the xmas tree was sold to me as a "P200" xmas tree; the spindle was an OEM "Piaggio" specifically for the P200 from SIP but it arrived wrapped in nothing but brown oiled paper, and with no markings.

Desparately seeking some advice. I've gone back over the old posts on the different xmas trees, spindles, EFL compatibility, and ended up entirely confused.

Case halves have matching numbers?

No numbers, they were new Piaggio cases.

I am not Darwin but I love to pitch in with my thoughts. I have put a P200E engine together and the kick start spring needs to have a finger load of grease to keep in in place and it also has the small L shape leg that has to be positioned correctly. Are you using both springs? the softy and the hard one? also, are you properly positioning the actual kick start lever? One or two teeth off can result on several inches of unusable travel.

Always get a feel of the kick start after temporarily closing the two engine halves. Also, is the inner half moon gear properly line up?

The only thing I can think off is that the spring has lost the strength.

All reasonable things to check. I'll run through them when the cases are split this fall. Maybe the strong spring isn't seated correctly. That could explain the inch of apparently spring-free travel.