tomos a3 will not idle and only wants to run at high RPM

I recently put a 44mm top-end speed kit on my Tomos A3. the kit came with a Dellorto SHA 15.15 carb and a bi-turbo exhaust. after fitting the kit the bike ran but not well. I wanted to get a bigger jet in it asap to not shred the engine running lean so I replaced the 68 jet that came with the carb with an 80. after doing this the bike ran for about two days however now it won't start unless I give it throttle or have the choke on. it will also occasionally get bogged down in the lower RPMs and as soon as I open it up again it sounds great. I am very new to this and don't want to continue running the moped if the jet is too small. what can i do to chase down this issue.

Re: tomos a3 will not idle and only wants to run at high RPM

Make sure everything is tight. While your idling (even with the choke on) spray carb cleaner at all your connections(intake/carb, exhaust, head). Once you've made sure all of your air leaks are gone now you can work on your jetting. You've taken it up high enough....maybe too high. Since you have a Sha I won't mention the screw...not much to figure out there. Get a handful of sparkplugs and start plug chopping! Unsure what that is? It's cool. https://www.mopedarmy.com/wiki/Plug_chop

You got a really light color/white your lean. bigger jet

It's a nice brown your good. stop

It's dark as shit your rich. smaller jet

^^ To simplify it :)

Have fun. A tomos will run damn near broken or even broken sometimes lol. It just won't run well. (also...you don't need a air filter on that sha...ditch it)

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