they are both mikuni jets from the same dealership. at first it seemed to run pretty rich when i warmed it up, but i used the old plug that came with it. when i put the new plug in for the reading it ran great, but no noticeable difference then with the 280, maybe a c-hair less power. i put the old plug back in for the ride home and it was doggy again, so i wont be using that old sum b again.
i dont think the resisted plug would matter, besides they were both the same br8es plug. but yes i am taking the carb off to change jets, because it is easier to not strip float bowl screws, and keep dirt out of the float area. but i was thinking maybe somehow when i put the carb back on the last time maybe it didnt seal up well around the boots, i dont know how else to explain it. the boots arent cracked, but maybe there was some dirt i missed? it hasnt been leak tested since i bought it a few weeks ago, but any new leaks that a leak down test would find would have to have developed in the 15 hours between plug readings. otherwise it still wouldnt make sense that the 280 gave a darker reading than the 290
i dont think the resisted plug would matter, besides they were both the same br8es plug. but yes i am taking the carb off to change jets, because it is easier to not strip float bowl screws, and keep dirt out of the float area. but i was thinking maybe somehow when i put the carb back on the last time maybe it didnt seal up well around the boots, i dont know how else to explain it. the boots arent cracked, but maybe there was some dirt i missed? it hasnt been leak tested since i bought it a few weeks ago, but any new leaks that a leak down test would find would have to have developed in the 15 hours between plug readings. otherwise it still wouldnt make sense that the 280 gave a darker reading than the 290