OP
UTC

Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
 
Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
UTC quote
I got my son in laws 2009 s150 carburetor type giving it the once over since he has not been riding it much. I was the previous owner so I know the history of the scooter.
It has 17,400 miles and has been maintained by a good local shop whenever something was needed.

The critters got into the thing and ate some wires (again) for the front lights,
battery was dead and would not start.
Charged the battery got it to start with starter fluid but would not idle.
Fixed the wires to the turn signals and front brake switch, took the carb apart and cleaned it but honestly it looked pretty clean blew out the jets with air compressor.put little wires through the jets seem to be pretty clean now.
Got it to idle great and seems to run smoothly.
Went for a test ride a couple times and it acts like a 50cc no pep.
Happened to have a new belt and variator nut in my parts drawer, installed that yesterday and it runs the same no pep. Rollers looked good so I cleaned up everything and reused the stock rollers.
It is still
Slow off the line and can't get it above 40 on the Speedometer.
Been driving it around anyway for errands and this is not the speeds I remember this was capable of.
I'm more of a vintage guy so any suggestions on what to look for I'd be grateful before I pull the carb back off.
I got thinking last night maybe a clogged muffler? It has the original stock pipe and is totally stock
Thanks I'm advance for any advice
Variator looks decent
Variator looks decent
OP
UTC

Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
 
Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
UTC quote
The variator picture where it is dark is just some discolored areas smooth to the touch.
This picture was taken before I gave it a hand sand to scuff it up before reassembling as per robots video
@crackedegg avatar
UTC

Enthusiast
2018 Vespa GTS300
Joined: UTC
Posts: 68
 
Enthusiast
@crackedegg avatar
2018 Vespa GTS300
Joined: UTC
Posts: 68
UTC quote
Could a worn out spark plug be the cause of no pep? Maybe a valve lash problem?
@juan_orhea avatar
UTC

Molto Verboso
S150 '09, Beo 500ie '08
Joined: UTC
Posts: 1367
Location: Bermuda
 
Molto Verboso
@juan_orhea avatar
S150 '09, Beo 500ie '08
Joined: UTC
Posts: 1367
Location: Bermuda
UTC quote
When my 09 S150 had those exact symptoms it was because the rubber diaphragm in the BACK of the carb - not the jet side - had a little wrinkle or kink in it, and wasn't sealing correctly. Take that side of the carb apart again, check the diaphragm very carefully, and run a tiny bit of silicone grease around the edge with your finger to facilitate a perfect seal. My guess is she'll be back to full strength.
@greasy125 avatar
UTC

Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15079
Location: The state of insanity, SoCal
 
Sergeant at Arms
@greasy125 avatar
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: UTC
Posts: 15079
Location: The state of insanity, SoCal
UTC quote
like Juan said, loop back and double check your work. what you're describing is text book for a diaphragm not properly sealing.

good luck!
OP
UTC

Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
 
Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
UTC quote
Thanks all for the input I'll check it out after work and report back
Chas
UTC

Addicted
PK50XL, PK100S, ET3, Matchless G80S, Honda CBR400RR, Ducati ST4S
Joined: UTC
Posts: 684
Location: UK
 
Addicted
PK50XL, PK100S, ET3, Matchless G80S, Honda CBR400RR, Ducati ST4S
Joined: UTC
Posts: 684
Location: UK
UTC quote
How old is the fuel?
OP
UTC

Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
 
Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
UTC quote
I drained the old gas out and put new non ethanol fuel
OP
UTC

Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
 
Hooked
'78 P200E, 2009 TMax, 2009 S150
Joined: UTC
Posts: 175
Location: New Orleans
UTC quote
Just took out the diaphragm and gave it a little grease and took a test ride runs like a champ now
Thanks for all the input
Y'all are the best!!
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