need help from the tuning gods

my 78 vespa grande tops out at about 21-23. the bike bog in the lowend and picks up in the mid but there is like no top end. and there doesnt seem to be any smoke comming out which kinda worries me, i am running 32-1 o and i just got it running today after it sat for like 20 years. the jet is a 47. the carb is cleaned out the petcock also, new fuel line, and a new plug. fires up pretty nicely but just SLOW. should i go richer or leaner? what jet should i get? zero elavation please help me out

Re: need help from the tuning gods

plug chop? and sounds lean to me

Re: need help from the tuning gods

mmm from all the way in how many full turns out should i do. just to help me get on the right track

Re: need help from the tuning gods

hey andrew, the screw on the carb adjusts idle speed, there is no idle mixture screw or jet, just the main jet and a little idle passage in the carb body at the bottom of the slide is the idle 'jet'. 47 is probably the stock jet, if the carb is be a 12.10, should be ok for the summer but you could go richer. do some plug chops to find out if you are running rich or lean, read about plug chops and how to read plugs in the wiki, also go through fred's repair guide.

you did not mention the exhaust, how is the flow? it could be built up with carbon, you can burn out the pipe and clean out the exhaust port on the jug

is the variating transmission under the left cover working correctly as the engine spins up?

Re: need help from the tuning gods

n this should prolly be moved to repair :)

Re: need help from the tuning gods

oh yeah, check the trans fluid in the hub in the rear wheel.

service manual:

http://www.mopedriders.com/article_view.php?faq=2&fldAuto=50

gl

Jesus knows all .. pray .. pray

HunkaHunka Burning Love /

and rear your manual because you can get a lot of bad advice on Moped Army (along with some good advice of course).

Re: need help from the tuning gods

the carb is a 12/12 dell. i got it alittle richer and it seems to be better. what jet do you recommend for the 12/12? 52? o and how do i move the thread to repair? can someone do that for me?

Re: Jesus knows all .. pray .. pray

the carb is a 12/12 dell. i got it alittle richer and it seems to be better. what jet do you recommend for the 12/12? 52? o and how do i move the thread to repair? can someone do that for me?

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