Still sputtering on the top ends of the gears ?
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Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1735
Location: Pioneer Valley Ma.
Thu Feb 19, 2009 1:16 pm quote
I just took the Rally out for a test drive. It sputters on the end of the gears?
I warmed it up for about 5min. drove up and down the street but it still sputters at the end of the gears 1st.2nd.3rd. did'nt get to run out 4th.
The carb. is spotless. Soaked the whole thing over night and had a Vespa mechanic clean it primaries & secondaries.

What else could it be??
Sergeant at Arms
Weird 80's Vespas & Cool Vintage Lambrettas
Joined: 21 Oct 2005
Posts: 7263
Location: The state of insanity, SoCal
Thu Feb 19, 2009 1:37 pm quote
sounds like a timing or jetting problem.

if your points are just out you'll get a little bit of flutter at the top end.

i'd suspect too rich of jetting though. but really, that's just a shot in the dark without hearing or riding it.

best,
-greasy
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1735
Location: Pioneer Valley Ma.
Thu Feb 19, 2009 2:11 pm quote
No points on a electronic Rally electronic 200 .

It idles nice and its great right up untill the end of the gears then it sputters a bit until next gear ect.??
Banned
2:6
Joined: 11 Jan 2007
Posts: 7382
Location: San Francisco
Thu Feb 19, 2009 2:21 pm quote
If it's all stock I'd suspect the ignition.

Is it load or RPM related? If it's the ignition then is should react the same regardless of load.

Try revving it out in neutral at ~1/2 throttle. does stutter at the same RPM or does it rev out cleanly?

If it's carb related you should be able to roll off the throttle just a bit when it stutters and it may clean up and accelerate more.
Member
P125X
Joined: 16 Mar 2008
Posts: 24
Location: The LBC
Thu Feb 19, 2009 2:58 pm quote
similar problem w/P125
I hope I'm not threadjacking here, but I'm having a similar problem w/my 78 P125. Six months or so since a new top end and new carb. My problem seems to be RPM related and accompanied by a buzzing sound as the engine winds up in each gear. In fourth, the sputtering and buzzing creep up as the RPMs increase at a slower rate than the other three gears. Sound and sputtering do go away as I back off the throttle.
Gatekeep, hopefully we can both figure this out.
Thanks.
Member
PX200, LX150
Joined: 11 Jan 2009
Posts: 12
Location: Singapore
Fri Feb 20, 2009 12:39 am quote
Try do some plug chops. It does sound like a jetting problem--probably running rich.
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1735
Location: Pioneer Valley Ma.
Fri Feb 20, 2009 2:52 am quote
edge-t wrote:
Try do some plug chops. It does sound like a jetting problem--probably running rich.
What is a plug chop?

I will mess around with the fuel/air mix a little later when the temp rises a bit. And I will of course remember where i started off.

I'm getting discouraged after all the time/money I put into it so far this winter.

I think this is going to be another live and learn thing.
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1735
Location: Pioneer Valley Ma.
Fri Feb 20, 2009 2:59 am quote
Good read I will check it out..
A plug chop simply means looking at the sparkplug to determine how you are jetted at a particular throttle stage. The only tricky part is in isolating the throttle stage. Before starting, clean your sparkplug and filter and warm the bike up.

To check the main jet, which operates from 1/2 to full throttle, get the scooter up to a steady full throttle or near to it for a good few seconds, then simultaneously pull in the clutch and kill the engine. Don't let the motor drag you to a stop, or fall to an idle, because you want to isolate the plug color at full throttle.

Get off and check the sparkplug color. (Links on our tech page.) It should be a light chocolate color. If it's white, the air/fuel mixture is too lean and you need a bigger main jet. If it's black or really dark brown, the air/fuel mixture is too rich and a smaller main jet is needed. If you need to change jets, change by one size, and do another run.
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1735
Location: Pioneer Valley Ma.
Fri Feb 20, 2009 9:56 am quote
ALL SET FOR NOW!

I think it was sputtering do to the fact that it was the first test ride of the season & combined with the 20deg. temp outside. I warmed it up a lot and went for a ride came back, then removed the plug it was a little oily so I tighten the mixture screw a little more then a .25 turn. after this there was Little or no sputter on the top ends of the gears.
This is all new to me

I also adj. the idle down a bit.

Have my fingers crossed.
Member
PX200, LX150
Joined: 11 Jan 2009
Posts: 12
Location: Singapore
Sat Feb 21, 2009 1:26 am quote
I have no experience riding below 28 degrees Celsius weather. Sounds like it was indeed a little rich. Hope it gets better from now on.
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