I think an Idle of 3000 is quite a bit high...<div></div><div>I'm able to get an idle around 2200 without nitro in my 46 engines (one magnum and one O.S FX)...</div><div></div><div>If your transition is rich....then your low needle is rich....the low needles control not only idle, but transition, that is the reason carb barrel goes in and out, they have a groove machined in a way to accomplish this, the more you close the carb, the closer the low needle gets to the spray bar (thus restricting fuel flow).</div><div></div><div>If I understand right what you say, you are closing the needle to get 200-300 rpm more from the 4 cycling..... that is definately RICH and definately not good for the health of the engine, not allowing it to come to operating temperatures.... high speed needle should be set ~300 rpm below peak RPMs...and then you adjust low needle. Unless is something wrong with something, you should be getting a niche idle about 2000 RPMS and a good transition if the needles are correctly set up.</div><div></div><div>Saludos,</div><div></div><div>Jorge</div>