Modern Vespa

Love the bike but nervous breakdown waits at the corner
9months owning lx 150 I 3v 2013 After service of 20.000 km including ALL needed (o rings,filters,valves,belt etc -mechanic said everything needed replacement and replaced ) bike runs way smoother BUT STILL .

1.cuts out when stopped 1 maybe two times in an hour city ride at red traffic lights(service didn't help to fix that problem).

2 .Radomly and rare more often when cold and 2 passengers on it stucks for 2-3 seconds when accelerating and after all OK (a problem that service solved at 90% but exists rare and less time stucked. it was 2-4 second stuck and not rare now its 1-2 seconds and rare BUT STILL THERE

3.Excaust pop//bang sound when from high Rev to low not always but not rare and more often when hot.

Mechanic is not a specialized vespa tech but repairs Kawasaki Suzuki Honda Yamaha piaggiov owns a gts 250 But after service exaust pops here and there which wasn't happening and engine cutouts at idle remains and no complete solution for mufle 2 seconds when accelerating tells me no special knowledge deeper at details.....


ANY SUGGESTIONS THAT will help what to check would be helpful to a new mechanic I ll visit

Thanks.!!!!

Any check engine light or anything? This is a fuel injected model right?

Acceleration from a a standstill or at speed (roll on)?
What is your level of handyman skill?

So the idle speed is a bit low and it pops and bangs during deceleration?

Hmm? There is an air leak in the inlet.

From low speed 10-20 km/h and sudden full throttle.
Theoretically I understand bike parts and interaction but hands are a different story.Reason of asking is to minimize another technician fault.😀thanks

Also could be that the throttle body/throttle position sensor needs a squirt with some carb cleaner?

Bung some fuel system cleaner into the gas tank and run around for a week.
May not solve it but it won't do any harm.

After replacing sensor L ,air fuel line,Beck that sprays gas i STILL have less rear mostly snifs than pops when iiding down and reopen A Litlle the throttle,only a little when full no snifs.Valve clearance OK,parts of injection cleaned etc.What makes the snifs not diagnosed even atg pisggio dealers software computer.

Any help what to look for further???