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‘74 SOHC carb on a ‘80 DOHC engine

CjMarty

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I have two bikes in varying degrees of disassembly. A 1974 complete bike but with a seized engine and a 1980 stripped bike with decent compression. I have two sets of carbs for the 1974 and none for the ‘80. Is it at all possible to use the ‘74 carbs on the ‘80 motor?
 
Not without a LOT of trouble. I looked into it a long time ago and there are so many things in the way it's not funny. The carb rack spacings are way wrong and you have no intake manifolds to make them work are two of the biggest reasons. The carbs will strike the bottom of fuel tank if they are the ones with the rods that pull out of the tops.
 
I'm actually doing the same thing. I got a set of '73 carbs going on an 82. I'm getting an aftermarket high tunnel tank so I'll let ya know if I run into any trouble or figure out any tricks

 
You really need to spread the rack out to match the DOHC, one of the biggest power killers on the design is the OEM kinked intake ports that match the already spread centers of the original racks. On the 4 valve head that kinking strangles the cylinder flow to mostly go through only one of the intake valves at higher engine speeds. A head with straight intake ports alone and nothing else changed is worth a solid 20-25 hp. by itself.

I for one am not sure of when the carbs went from 4 cable (easy to spread them out) to full mechanical linkage (harder).
 
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