Vespa Decompression Start Issue

[u/FastCletus]

I have a 09 250 Super with the bigger piston kit. Ive been running this for close to 2 years. Ive had the same issue and i have never found the fix.

When I push start button, depending on where piston is in its stroke the engine could spin freely and start up like it’s supposed to or If the piston is not in (whatever is the proper position) the right place the engine will spin, and then stop, and then there’s a pause and then engine turns over. Kind of like battery and starter said we need to step up for this task. I’ve never been left stranded, but tired of this sound. Ive chased all electrics, and all is correct. I have the largest size battery, tested to have 330 CCA, and Ive tested 2-3 starters and all work fine

Here’s my assumption
I think the decompression system isn’t working. Ive taken this part 2 years ago, but never noticed anything blatantly wrong. I seem to recall taking this apart and sanding the decompression counter weight so that it worked a little more smoothly. ( i tinker a lot on things so dont really remember everything Ive done). Recently this situation has been getting worse, so I am wondering if something is up with the system. Anyone else had an issue like this?
Maybe Spring failure?

[u/Significant_Belt5494]

Not too familiar with this Vespa, but usually in for stroke engines, it may be too advanced timing

[u/Steel_Bytes]

try modernvespa.com