M Saunders
CB750 Member
I have a stock 74 cb 750k that i am having problems getting it to fire properly on all 4 cylinders. I rebuilt the carbs and bench synced them and set proper float height. I Installed new plugs, plug boots and points I gaped then dweld the points then set timing. cylinders 3 an 4 seam to run good and 1 and 2 dont cyl 2 pops in the exhaust and its exhaust pipe runs 30*f cooler than the rest but when i pull the plug it looks good not fouled. Cyl 1 runs same exhaust temp as 3 and 4 and dose not pop in exhaust but it seams to miss out at around 2500 and fouls the plug really bad dry and black carbon. I did a cold compression check on all 4 cyl they were about the same i think a little low around 90 psi. I will do a hot test later today. the motor has 12000 mils and has set for 20 yrs. I would greatly appreciate any input or info that could help me.
when i checked the compression i forgot to have the carbs all the way open it is really exactly 140 psi on every cylender I did this test with a cold motor and did not add any oil to them
when i checked the compression i forgot to have the carbs all the way open it is really exactly 140 psi on every cylender I did this test with a cold motor and did not add any oil to them
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