Modern Vespa

Ok, so I have cleaned out a fuel system, replaced tap and cleaned jets in the carb to get 74 vespa rally 200 running again. and voila, got it to kick over but only with choke fully out (put choke in it dies). The engine sounds good but a little rough, and a turn of the throttle and bogs out. I let it idle, but then it eventually bogs out. Is this the idle and air-fuel screw adjustments? I found some articles online but very vague. Any thoughts on how to get correct idle/throttle?

could be an airleak... did you torque all the carb bolts down correctly?!

Sounds like a air leak. Maybe take the carb off clean the pathways out soak the shit out, blow all the pathways out with air slap in a carb rebuild kit$20. Make sure you carb is flush on the bottom by placeing it on a piece of flat glass.When you replace the carb make sure to use a torque wrench.

If this does not work then you have a leaky seal. IMO... Brian

How many miles are on it?
What work has been done to it?
Any history?

bogging is a lean condition. did you start at 2 out for the air/mix screw on the back side and 3 1/2 out for the idle?

for tuning your carb its really very easy, just dont over think it alot and check the plug at lots of different RPM's.

http://www.vespamaintenance.com/fuel/carbtune/

I will get carb. rebuild kit. and keep following fuel. I am sure I will end up rebuilding the entire scooter by the time I am done

M.

lol you say that like its a bad thing

I sent my Rally engine out to New Jersey in January for a major to spec.rebuild and Although we did run into a couple of snags ( crank/ top end) its still been a long time. If your planning a major rebuild do it all at once and save some time and $. Summer is just ticking away here. It's a good thing I have the P.

Wish there was a vintage shop based in NE... May it run it down to RI, if problem bigger than I.

As for the summer weening on, this is probably why there are more vespa's in CA... more time to fix.

That depends on where in the power band it's bogging.
Bogging can be a condition that is lean or over rich.

Let me know if you go to RI. I would like to hear about that shop.