Hi, I have a Piaggio Zip 2t AC. I have just fitted a new 21mm carb and now my set up stands at Malossi 70cc kit, universal PHBG 21mm delletoro carb, stage 6 open air filter and a yasuni exhaust, I am not sure on the roller weights. At the moment I have a small collection of jets, a 65, a 90, a 95 and a 102, right now I am running the 95 and it is bogging on low throttle but high throttle is fine, it just seems as though my accselleration is rough and deprived of fuel, I have the fuel mixture screw around 3/4 from fully out but is still held well in place and have the air screw 2 clockwise turns from all the way in, this mixture I have found the most officiant at the moment. Tommorow I am going to have a look at the needle and change it to a different grove, maybe leaning out the mixture so not so much fuel gets through, I am still not sure wether I am running too rich or lean on this set up, I know when I ran it on the 102 jet is seemed evident that it was rich so I down jetted to the 95, I could down jet again tommorow to the 90 with the same mixture. There is a tiny split in the manifold but I'm not even sure if air could get through it's that small but even still there is the chance of a air leak. I have been trying to get my moped perfectly running for a while now so I was just hoping someone would have a rough idea on what main jet I should run on this set up for the best performance, I have also heard of the pilot jet being involved on lower throttle ranges. Cheers, Dan.
dont worry about pilot jet its more idle than mid range. drop the 90 jet in see ow it reacts could find the 95 is just a tad to rich. the needle you wnat to move the clip up a slot or two ( up on clip slots means leaner mids --- lower needle slots mean richer )
put 95 back in and play with needle setting see if that helps , also seal that hole /split in the manifold so theres no airleak
