I've been working on a friends moped and when you give it gas it will start to speed up then Cut out then Speed back up...then down ECT. When it finally warms up it will have little cut outs on/off. any help would be appreciated this is a 1978 Hero-majestic Ankur.
Have you cleaned the carb properly?
upjet. its too lean, thats why it cuts out less as it warms up.
It does seem like symptoms of a air/fuel mixture problem but i wouldn't blame it on a main jet size yet, unless you changed jets or modified the engine just before this started.
Sounds more like a vacuum leak.. or something is way off, like the float level.. or dirty carb.. an intermittant, partially blocked main jet.
Basically sounds like an inconsistant flow of fuel into the intake manifold..
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