Modern Vespa

Has anyone changed out a check valve?
Want to know what is involved.
Believe I need to do so on the BV350, but find no info anywhere on such a procedure.

First start of the day is always sluggish. Had the fuel injector cleaned, hoping that would solve it, but no (injector didn't need cleaning as it turned out).

Guy who did the cleaning said it sounds like the check valve isn't functioning properly.

What's the mileage on it? Is there a check valve in the fuel line? Not sure there is one but if there is it would show on a parts list.

If sluggish during starting, it could be the exhaust valves need to be adjusted.

My BV350 always turned over a little slowly on its first starts of the day. I just reckoned the starter was a bit too small for the engine. Be sure your battery is in good shape.

The new BV400 too growls a bit then it's started.

13,000 miles. Not sure if there's a check valve in the fuel line, figured there was.

It's always been slow to start since I got it (660 miles). Battery is strong. Could the valves get out of adjustment in the first 600 miles?

Not likely. The BV350 uses shims instead of locknuts, but at 13,000 miles it's about due for a valve clearance check.

Not an accurate statement. Piaggio is confident of their shimmed valves. First check at 40,000 km or 24,800 miles.

My mistake. It's not due for another 12,000 miles.

What do you mean with "a check valve"?
You refer to this guy saying "the check valve is not functioning properly". What valve?

Believe it's a part that regulates fuel line pressure/prevents backflow?

I never heard anyone mention a check valve on a piaggio scooter. possibly they meant checking the valve clearance?

Do you have the evap crap in OZ? Because there is a roll-over valve between the tank vent nipple and the charcoal canister in places where the evap crap is installed. This could well be described as a 'check valve':

https://www.scooterwest.com/valve-for-canister-cm028201-576461.html

Evap crap, no. A rollover valve, yes (but it's different to the one you linked). But I wouldn't have called that a check valve myself and haven't heard anyone else do so.

You can 'check' something by stopping it. e.g.: "efforts were made to check the disease" (example pinched straight from google).

So a stop valve if you will... "Volet" in Italian?