Topic: 1978 CB750k, project "Crimson King"

[Bonesaw]

Starting from scratch, here's the bike in the beginning:



Here's the bike as it sits now:



Planned upgrades:
*K&N filter w/stock airbox, or pods, haven't decided
*120 jets upgraded from 110
*4-1 exhaust
*pamco ignition setup w/coils
*solid state rectifier/regulator
*better battery
*braided stainless brake and oil lines
*new gaskets and bolts for the engine
*valve lapping, or valve job depending on how they look
*superbike bars and GT grips
*new shocks/springs
*carpy's "shark" cafe racer seat (still want to hold 2 ppl)
*engine color - flat ceramic black
*frame color - gloss black
*tank, side panels - deep metalflake red

This is gonna take all winter and then some, gonna be a slow build but worth it!

[theofam]

Carpy's shark seat will look sick with that fairing!

Great to see another candy alpha red '78K on the forum.

Watching with interest.

[lucky]

Any updates?

[Bonesaw]

Just started on this, its gonna be a long winter project. Here's what I've done so far:

cleaned and painted oil tank flat black
installed 120 main jets, cleaned carbs
polished the brake/clutch levers
cleaned and painted the brake master cylinder gloss black to match frame.

I have superbike bars in the mail, as well as some nice new acorn nuts for the rear shocks, when I get them.

[Stev-o]

Please tell me you will take the fairing off?!

[Bonesaw]

yes, fairing is off and will be staying off. Its for sale in the appropriate section on this board. It works great, I just don't like it.

[Bonesaw]

Here's the superbike bars, reconditioned MC and GT grips mounted:

[Bonesaw]

update today - reconditioned the front caliper, new brake pads, caliper seal (OEM), stainless braided brake line from Slingshot (thanks for the custom length, it fits like a glove), new stainless caliper piston, speed bleeder, and DOT 4 fluid. Can already tell a huge difference in the front brake with these upgrades.

Next up - removing rear wheel and changing drum pads, new swingarm bushings, and 530 chain conversion

[Bonesaw]

Ok, getting ready to do a 530 chain conversion, need some advice.

My research is showing that a 18T front sprocket and a 48T rear will be pretty close to stock, is this correct?

Also, for the 530 chain, the correct length should be 104 links? O-ring or non-o-ring?

[lucky]

You do not need the "O" ring chain. A regular 530 chain with masterlink will make everything easier. Less tools.

Many of you have been talked into expensive O ring chains.
Many of you have been talked into $700. Garbage can mufflers.
Many of you have been talked into $500. Foot rests.
No need for all of that.

Regular chains have worked fine for over 70 years.
Matter of fact with the modern chain lubes.
Now the lube does not come off. Just apply the chain lube and the next morning it is ready to ride. The lube goes into the rollers and coagulates .

Also just buy the 112 link chain. You will have to remove 3-4 links.

Chains come in standard lengths and then you use your chain breaker tool to remove the links not needed.

Move the rear wheel all the way to the front of the slot and wrap the cain on the sprockets. You will see which links need to be removed. Do not forget to remove the pin that leaves the correct part of the link.

[Peacefrog]

I got bit with a shorter chain. I think I had to buy 110, and used ~106? First time around I got a 104 and it was a couple links short. I am running the standard chain and put 1000 miles on last fall, chain didn't stretch much. And it was 35 dollars vs 100. The 78 has a longer swingarm and a different front sprocket mounting bolt. Cush drives are wider also... tried to swap cush out with sprocket still bolted on. Your bike is identical to mine, but mine lives in the basement. And my winter project was bearings and bushings.

[Bonesaw]

Ok its been awhile since the last update, but my time's been taken up by my new puppy (cane corso) and my car (blown engine). Anyway, here's what's happened in the meantime:

New shocks installed
engine removed from frame (PITA, had to lay frame on the side and cherry pick the motor out)
motor broken down, many screws destroyed by impact driver (got a bolt set coming)
new HD cam chain installed
covers sanded, primed, and painted high heat flat black

coming tomorrow or next week:
4 new turn signals
headlight installed
piston rings installed, engine reassembled for cleaning
frame cleaned and paint touched up

Pics:







and one of the puppy:

[Bonesaw]

ok I have the block back on the cases, just waiting for a buddy to help me get these danged exhaust studs out of the head (2 of them are froze bad).

Dropped off the tank and side covers off at another buddy's for paint, it will be gloss black with metal flake (either regular or california rainbow, haven't decided). He's also gonna chop the  rear fender down and paint that the same color.

[Stev-o]

Are you still waiting?

[Bonesaw]

finally got the head back from my "buddy" lol. Turned into a massive ordeal to get my parts back from him. Not asking him to do anything again.

Annnnnyway... Tank and sides painted gloss black with 5 coats of clear on them. Rear fender was bobbed, sandblasted, and painted gloss black. Frame was also done gloss black lol.

In the process of putting the motor back together, couple small pieces got lost in the garage so I gotta find them somewhere now.

[Bonesaw]

OK progress update. Got the motor back together and have started to assemble things. It's kinda slow going because I'm dirt poor but its coming along. Here's some pics:





Not really liking the stock seat, I want to get something smaller but still want to have the ability to ride 2 people on it, any ideas?

Need a new brake mc, the old one has started leaking for no reason.
Need a set of oil lines
Need a brake light and license plate bracket
Need a few other odds and ends

[Bonesaw]

OK its been awhile, made alot of progress, but unfortunately more work to go too.

Got the oil lines
Got the engine to fire! Big milestone for me as I wasn't sure it was gonna work, for some reason.
Most of the electrics worked first try! blinkers, headlight etc fired right up

Current issues:
Neutral light stays on no matter what gear I'm in, any ideas?
stalls out, but I think I just need to synch the carbs and that will stop
have to readjust rear wheel as I left too much slack in the chain
leaks oil from the left of the engine from inside the fins. I'm sure I torqued everything down right, I don't know what I coulda missed.....