I could understand if jets were not available. I dont think jets are expensive. Drilling or filling of jets is not consistent. the diameter could change form start to finish. no guarantee that the hole will be round. Could introduce turbulence into the flow. etc, etc, etc. The best part is, what exactly is the size. Is it a 105, a 110, or is one 125, one 128, 118. I will purchase jets. multiple carbs are trouble enough without wondering what size the jets are.