hello overtone I have a 1977 cb750k that ive had for a while now and have finally got it almost where I want it the only thing now is I can’t get the bike to go above 75. I know it’s not necessary to go much faster but I live off a dangerous road and sometimes I like to get away from other drivers if I can. It starts and idles flawlessly and even revs up and returns back to idle very smoothly. I’ve got a 38 slow jet and a 130 main in it. I also had a 125 in it last week but still had the same top speed. I’ve had this bike up to 115 mph before but at the time I did have round top carbs on it I now have the later key hole version. Could it be carbs? Or could it be cylinders? Anything helps thanks for your time