Carby carb upgrade gone wring

[warriorairman]

So I have an "80"cc HT I wasnt pleased with the nt carb that came with it, it leaked and I had to keep the idle high, so I bought a dellarto clone off jnmotors.com the carb is nice but I'm not getting top speeds that I would like I lost a lot of speed almost 15mph. It use to top out oround 35 now it sruggles to get to 22. Is this just how these carbs are or is there something easy I did wrong? Thank you

 

[Bzura]

Your jet is too big. The jet that comes in those carbs is usually a .78. MOST HT engines run best with a .70 or .65 jet - depending on your setup, elevation, etc.

Check the plug color, and you'll fund its probably black and oily. Indication of too rich a mixture.