OP
UTC

Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
 
Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
UTC quote
I have a 2009 carbed LX150 w/just 500 miles that runs ok under load but idles rough. It is emitting black smoke at the moment and I'm assuming it is a rich condition. I ordered a new petcock thinking that there maybe fuel entering the vacuum hose but just realized that this model has no vacuum hose coming from the fuel tank, but a direct feed style petcock that sends fuel to a fuel pump. The EVAP hose has been disconnected from the carb but makes no difference when connected. Any suggestions on how to proceed with cleaning up my situation? Thanks in advance....
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@cosmos avatar
UTC

Addicted
2009 LX 150, 2024 GTS Super
Joined: UTC
Posts: 926
Location: Birmingham, Alabama, USA
 
Addicted
@cosmos avatar
2009 LX 150, 2024 GTS Super
Joined: UTC
Posts: 926
Location: Birmingham, Alabama, USA
UTC quote
I'd check that the air filter is clean. Next clean the carburetor. I recommend this video to see all the details:
OP
UTC

Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
 
Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
UTC quote
Thanks for the response- air filter and carb are clean and inspected..
@greasy125 avatar
UTC

Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15080
Location: The state of insanity, SoCal
 
Sergeant at Arms
@greasy125 avatar
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15080
Location: The state of insanity, SoCal
UTC quote
check the function of your auto choke. it's likely gummed up or sticking.

have you cleaned the carb?
OP
UTC

Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
 
Lurker
ET4 LX150
Joined: UTC
Posts: 3
Location: NY
UTC quote
Carb is squeaky clean and blown out…float's don't appear to be sticking…
@greasy125 avatar
UTC

Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15080
Location: The state of insanity, SoCal
 
Sergeant at Arms
@greasy125 avatar
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15080
Location: The state of insanity, SoCal
UTC quote
did you mess with the A/F adjustment or the idle speed at all?

it's unlikely that you've got the A/F backed out enough to be so rich as to produce black smoke, unless you've got an airleak somewhere and you've adjusted the idle speed a massive amount. so, unlikely.

back to auto choke.

and I'd check the spark plug and cap while I was there. just because.

just as an aside, it's possible that the air filter could be so saturated that it is causing an overly rich condition, and while the bike would idle it would run like hot garbage.
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