I found out that a 1972 carb mount plate will fit the 1969 carbs with
very little modification. I bought carbs that did not have the mount plate and I have seen several other photos of broken carb mount plates for the 1969 carbs.
I also found out that the 1969 carbs will fit the 1978 carb mount boots by
just tightening the clamps down. There was a .060 difference.
The 1978 carb mount boots are shorter than the 1976's.
BTW...I put the 1969 carbs on my 1978 CB750 and now it runs great with perfect throttle response from idle.
I have #120 mains #40 idle jets and clip on the middle notch. Otherwise stock for those carbs. Mixture screws out 3/4 turn.
Good results on the road test. Accelerates hard and just keeps accelerating at WOT.
The mixture screws are very sensitive to adjustment- they really respond. 1/8 turn makes a difference between backfiring on decell or NOT backfiring on decell.
