Modern Vespa

Hello everyone. I've got a 1978 P125X it idles and runs well. I've been having some issues with it trying to accelerate from a stop. I've read many other threads online and couldn't really find anything that addresses my issue.

When I kick the bike on and shift into 1st the engine still runs fine. However, when I release the clutch there is a few different things that can happen. I'm not sure if there is an issue in the bike I need to address or, if it is just user error.

If I shift into 1st and then let the clutch out quickly the front tire jumps up and the engine stalls. If I ease the clutch out then sometimes the bike will get rolling but, the RPM's drop very low and the bike begins to accelerate very slowly before gaining speed. The other situation that can occur is that I release the clutch slowly and the bike will roll forward just a bit and then stall as the RPM will still drop very low.

I'm confused on whether I just need to be very sensitive with the clutch and that is how the bike operates or if there is something I need to look at within the engine. I would appreciate any help anyone can offer, Thanks!

I suggest you let someone more Vespa-experienced test drive your scoot.

You've gotta give it some gas as you slowly release the clutch. If you've ever driven a stick shift car it's the exact same just with your hands rather than your feet.
Sounds like with A you are releasing the clutch way too fast. With B it needs a touch more throttle and C is the same as B.
A good idea is to hold the clutch and SLOWLY loosen your grip until the rpm's drop. That's the point where the clutch is releasing. You add a little throttle at or just before that point. It'll take a few practices to get it right. The slower you let out the clutch lever the better until you figure it out properly.

Could be many things...

Has it been ages since it's been ridden?
If so, clutch plates may be sticking together, Which will cause it to suddenly catch/engage

Is there oil in crankcase?
If not things will be sticky-together-ee

Find a HILL or call a FRIEND to push...
get it running...
Pop it into gear, but keep clutch in...
Get that puppy rollin'...
Blip that throttle...
Ride that clutch & off ya go.
If it wants to stall, grab the clutch, give it some revs, try again.

REMEMBER: SAFETY FIRST... Helmet, gloves, full body covering!
That makes it far more enjoyable when you fall off or crash!