Modern Vespa

i had jets cleaned by dealer...was told needs to be done yearly. LX50 ran good a couple of days...then wouldn't start. i put new premium gas in this year. bike has 150 miles on it. won't start i added 1/2 can of Start to the gas tried kick start about 20 times to get mixture. did electric start and it only runs about 1-2 minutes and sputors out. i am now cleaning filters but they don't look dirty. What is possible problem i bought bike new has 150 miles but it was a 2009...sat for awile

My guess from experience is a dirty carb. Not from use, but from non-use. Fuel evaporates leaving a deposit that can clog up jets and restrict flow.

Disconnect your evap hose, you may have over filled the tank and if fuel gets in your evap system it will cause the scooter sputter out, a very common problem with that evap system. Good luck!

1/2 of can of WHAT? start ? what the heck is that? did you read the mixture ratio on the can?

Drain the whole gas tank and put in just fresh gas.

Aloha and welcome to the forum. They really like to be ridden more. Take it back to the dealer. Sounds like they might not have done a good job. Never heard of Start. Is your battery alright? Do you put some stabilizer in it and hook the battery up to a tender or disconnect it when it doesn't get ridden? You could try what DIRT said and i would add a touch of SeaFoam to the new tank. 3 years old and it could be a dead batter since your not doing long rides to charge it. Test it to see if it's ok or get a new one. Might solve part of your problem and put some fresh gas in. Hope you get it up and running soon.Good luck

is there a fuel filter running from gas tank to carb? if so could that be restricting gas....looking for possibility since jets were cleaned 4 weeks ago