I looked at the manual on line for rieju 300 - unless your importer swaps it out - it will come with a n1ef needle. So you will want to replace that before you ride it. Some use suzuki needle or yamaha needle with very good results. Look for posts from "jakobi" as he is the jetting expert here.
With the n1ef - you don't even want to waste any time trying it out.. You will end up way lean on your pilot and have your idle cranked up.
With a "good needle" in it - it will idle well and start well.
jeff
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