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Oil Change Now it Knocks

GiDesign

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my 81 cb750F runs great, then change the oil (Valvoline 10-40) suddenly sounds like rod knocking. like it might throw one in the next 50 miles.
what the heck. could it be that it doesnt like the oil???
 
my 81 cb750F runs great, then change the oil (Valvoline 10-40) suddenly sounds like rod knocking. like it might throw one in the next 50 miles.
what the heck. could it be that it doesnt like the oil???

nobody has a comment on this ??
 
Dont know what to tell you. Probably has a loose bearing in there and had thicker oil in it previously which helped to cushion the bearing. What did the old oil look like? Was it sparkly, thick, how did the oil filter element look when you had the cover off, did it have some metal settled in the bottom? Has to be coincidence with the oil change. Have seen car engines take out a bearing after fresh oil when the previous owner severely neglected the car by never doing oil changes...the thing was on its way out but by draining the old thick dirty oil out it took away the only cushion that kept the bad bearing in tact.
 
too much oil?

can a bit too much oil cause a knock? it knocks only in certain rpms when riding (that i can hear)
i put 4.5 qrts in and it is past the oil safe zone on the dipstick about 3/4 inch
 
If the oil is overfull it can cause the oil to aerate which can cause oil pressure issues if it is bad enough. Cant say for sure if that is enough but it is quite a bit over full. oil capacity should be 3.7 qts.
 
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