1984 nighthawk 650 4-1 exhaust options?


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not alot of aftermarket exhaust options for the nighthawk dohc 650

ive done some research but some say its the same as the cb500 exhaust and some say the cb750 exhaust will fit
will all DOHC models fit?

Looking for a 4-1 exhaust
Got a '77 CB550 and same as 500 and no way does it fit. And virtually all Honda DOHC change pipe systems, they hardly interchange at all other than the 750-1100 early ones.

There was a DOHC 550 Nighthawk, that one might be close. The early 650 SOHC definitely does not fit.

Honda changing designs almost year by year there and very few bikes got sold either, why there is nothing in the used pipeline to draw on.
The 550 engine looks closest but the stroke is a lot shorter making the cylinder block shorter too. That makes the exhaust pipe shorter in the vertical run to likely hit bottom of engine with no clearance at the pan.
The inline 4 bikes just run lean in those years, counting the entire later DOHC pack of '84-'86 550, 650 and 700 I can't say I've seen 10 of them total since they were made except when I walked into a showroom. Honda was too busy thinking V-4s around that time. Then most who bought them never put a header on, it ruined the lines of the bike to that type mentality, I don't think I ever saw a headered one in all 3 of those. Thinking very few headers ever got sold or even made to begin with.

The bikes are considered 'custom' and most want the full 4-4 or 4-2 pipeset, a one-sided header spoils the 'look' too much.. Even the bigger C model owners prefer 4 pipes but are forced to go to header later when the owner cannot find the 4 pipeset. More likely to find a header for the plain jane K or F type style of which those 3 never came in.

V-4 models the same, the headers for them were quite expensive due to the needed design and they sounded pretty bad anyway, the V-4 sounded like a straight 4 running bad, like a cylinder not working, a flat dead sound.
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