I met up with a guy selling a '73 CB750 in the Dallas area to check it out and he ended up selling his for $5k; it was all factory original, pristine, and apparently had Fox upgrades from the factory(something I never knew about). Boner and drooling may of occurred.
I'm kinda thinking like 754. Stick to your guns. You got what they want but everyone wants to win. I'll give you my honest $.02 and share how I'd do it. Don't hate me.
You might be advertising wrong. If you're on Craigslist you should definitely be marking up higher than your bottom dollar. The ol, "craigslist's game". I read you should go 10-15% higher than your ideal target to give room to negotiate down a bit. Check eBay completed listings to make sure you know what prices have been averaging lately.
Everyone wants to play "Pawn Stars" and you just have to play along. If people contact me asking price I'd tell them "I don't talk prices over the phone/emails, that's an in-person conversation after you check out the bike and see what you're getting." Then you can cut the crap of the low ballers and those who aren't serious.
The ad comes off a little too "SALE!!" to me. I'd probably lose the sales stickers at the opening (Title!, $3k of parts!) and the pitchy stuff ("looking for a sweet vintage bike?") and keep it simple and factual. I'd also say market to the folks that don't know or need to know the fancy terminology and other stuff like models, you'll just confuse them!
Any Honda head will contact you and ask the important questions. Keep it simple for those that don't know what "honed" means. Aim for the kid with daddy's money that wants a ready to go bike. (Yes I'm going to hell)
I'd also lose the itemized pricing of parts; it makes it feel like you're trying to get your money back. Then I ask myself, well if it has all these badass parts why's he getting rid of it? Is it a botched restore? What's being hidden? If I tally what you listed I come up with $2,358 and not $3,000; some bozo out there will bust your balls for this.
My take, [reasoning/text to you/what the reader will think in brackets]
"Up for sale is a titled 1978 Honda CB750 Four Super Sport street motorcycle [tags for search hits]. Bike has original keys and has been completely restored and had an overhauled K(performance version) engine installed and is ready to ride [overhauled, performance AND ready to ride!?]. Bike runs, drives, shifts through all gears, stops, holds idle and has no issues [knock out stupid questions to your email]. This thing has $3,000 worth of parts and upgrades but keeps it's 70's style with 21st century performance. [ok, just a little pitch

]
Here's the short and sweet.
Engine overhaul
OEM Piston rings
OEM Cam chain tensioner cam
Vesrah Complete Gasket
Clutch lifter plate
Stainless steel engine bolts
Frame
Powder coated
New IRC Tires
Cycle-x 4-1 exhaust
Chain
Front and rear sprockets
Clutch Cable
Shocks
Grips
Brakes
Front Master cylinder rebuilt
Brake pads
Seals for front and rear calipers
Speed bleeders
Electrical
Smart [people love smart stuff] Motogadget M-unit system (
https://revivalcycles.com/products/motogadget-m-unit-controller)
K&S switch
Deluxe cables (
https://revivalcycles.com/products/revival-cycles-deluxe-cable-kit)
Ricks Motorsport Starter Solenoid
Ricks Motorsport Rec/Reg
Shorai lithium ion [hey my phone's got a lithium ion, that's smart!] battery
Points and plate
Gas
Carb gaskets
Slow Jets
Gas lines
Petcock
Cables
Clean and clear title in hand. Asking $5,500 OBO. [give room for both parties to win/ start high and let them take you down or knock it down yourself (I'll tell you what Brad, you seem like a cool kid so I'll let it go for $5k)

]
CB, 750, 754 [I found my K2 project titled like this], classic, antique, vintage, original, restoration, cafe, racer, yamaha, kawasaki, suzuki [muhahahah they wanted a suzuki till your ad popped up in their search!]
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I said don't hate me