Modern Vespa

Howdy,
Stalling/loss of power when warmed up and then no restart after cooling down, even for days.

Ideas/mechanics near me?

Carb has gas, gas cap ok, fresh fuel.
Replaced starter gear and over 400kms since then and now this!?!?I

Suggestions?
Thanks

Nobody have any ideas!?

How long does it run when you get it started?

How are the fuel lines, petcock functioning? Ever been replaced? This is something you can check by removing the line at the carb and putting it into a container you can see into like a glass jar and then disconnect the line at the intake manifold. You can suck on this vacuum line lightly and fuel should flow freely.

IDK if the ET4's suffer from bad CDI's or not but your issue kinda sounds like what a bad one does to the LX's. Our remedy is to purchase the unrestricted one. I have revived three late 2000's LX's and they each needed a new CDI after quitting on the road during a ride or cutting out for no reason. In this scenario though I was able to restart after the unit cooled down so maybe not your problem which made me think of the gas supply side of things.

is your evap line still hooked up to the carb? if so disconnect it. if the charcoal canister is saturated then that could explain the no start for days.

but just to confirm: when you say no start do mean it's turning over and it just won't catch or you key it up, press the button and get nothing?

how many miles and what other items have been replaced or maintenance been done?

Thanks Dude,

Yes vap line off.
Cranks over but won't fire.
Got gas supply to carb.
Got spark.
Got compression.
36K kms, no other mods.

So how / when does it finally start? A few days later it just decided to run again?

When it wont run, does it try to start or nothing at all?

Does it restart easily when it finally goes (like a bad connection that reconnected), orders it struggle and sputter and finally go?

Hasn't run yet this week, was running ok for about 400kms after the starter bendix fix.
Was running ok then sputtering, lost power and won't restart.
9 pm walk home in 30C heat...

Oh, so this only happened the one time, and the bike still has not restarted since then?

Why did you replace the Bendix gear?

Did you have any clues of bad running before this?

Is the bike up on maintenance, like good working battery, vacuum hoses in good shape, valve clearances?

Thanks,

It's been a few times before and after the bendix gear replacement that it has lost power and stalled but would restart, not this time, nothing.

Fuel, petcock all good.

Thinking electrical, cdi or coil maybe?

have you tested the stator, mainly the ignition coil in the stator?

but now I'm interested, when it doesn't want to start what kind of flash code do you get in the dash with the key on?

either way, start with the cheap and easy stuff first: check the battery to start. check your grounds! especially the one on the trans cover! then run the ignition system back. check the cap, check the plug the one that's actually in there not a spare grounded to frame, check the HT lead and coil and coil connections (these occasionally get corroded). then check the stator, both hot and cold. check your kill switch. then check your key (test with the master) and antenna. check the leads at the CDI.

hopefully that will put you on the path to not going insane and just throwing expensive parts at it.

good luck!

Thanks, appreciated, but ya got spark!

Sorry, it has flash codes?
Don't see any, it's 2006.