Hi, we built a 70 cylinder on a Honda Mb5, because the 50ccm was not enough. So far we have only made the engine run 2 times short. Since it was running too fat at first, we moved the main nozzle needle from the lowest notch to the middle, but that did not bring any improvement. Ignition sparks is there, also otherwise everything is in order. How do you have to adjust the carburetor, so that the engine runs reliably? It is about the originals. The purpose of the conversion should not be to be able to saw all the others now or to get the maximum speed and acceleration out of it, but rather to be able to keep up with it, because before that there was no more than 45 km/h in it and uphill the first gear was called. Can someone help us further? mfg Michael