CB750 K0/K1 Hybrid

[Lucien Harpress]

...funny story.

The owner came to me and informed me that he has no time or money to finish this project. So he offered it to me for $300.

...

I haven't decided if I'm taking him up on it yet.

[salukispeed]

These are not cheap adventures or for the faint at heart. I agree with Fish. Title, Do any and all safety things and ride the old beast regularly.

[Lucien Harpress]

Well, okay, bit of an update.

I waited a bit to long to pull the trigger on the offer, and the current owner's (my buddy's) girlfriend basically told him he couldn't sell it. Something about "it makes you happy, and you'd regret selling it". HIS words to me were, "When she gets tired of seeing it, I'll let you know".

I let him know that, when it's back on the market, I'll take it for $300.

So yeah. My plans (if I can buy it) are to put as little money into it as possible. Buy an airbox, tires, cables, MAYBE a tank if I can find a solid one cheap-ish, buff as much rust off as possible, and just ride it. If I enjoy it, keep it and, if not full restore, at least REALLY clean it up at some point. If not, flip it for some cash. Either way.... I'd like to own a "classic" for a bit, you know?

[5speed]

the guy I bought my wing from has a restored 750four, a restored 550four and another 750 waiting for restoration.

[Lucien Harpress]

UUUUUMMMMM yeah.

So I bought it.







I like the moss on the crankcase. That's a nice touch.





There is.... a lot to go over. From what I can tell, everything is there except for the airbox (the carbs I have inside). I may have gakked the carbs a bit when I pulled them off the bike, so I'm hoping I can get parts- I really don't want to dump the money for a whole new rack. There is just one part of the exhaust on the lower left muffler that concerns me a bit, but other than that everything looks solid, if a bit.... okay, a LOT dirty.

She DOES turn over though, and has compression. I'd like to hook up one of my batteries, just to see what works electrically and what doesn't, but I can imagine I've got a LOT of going-through to do.



But hey.... CB750, right?

[Dog Boy]

I bought that same bike, new in 1973. That was a sweet ride and the orange metal flake really looked good!

AL

[Lucien Harpress]

Did a VERY limited amount of exploration today, to kind of see what I'm dealing with. I hooked a battery up and, sure enough, absolutely everything was dead. I managed to get the starter turning by jumping the solenoid with a screwdriver, but that's it.

I don't want to jump to replacing the entire wiring harness just yet, because I have no clue what's to this electrical system. I DO know that both handlebar controls are probably write-offs, which can't help things any. I've got a service manual coming in the mail, so I'll do a bit of research with that before I start pulling things off.

In the meantime, I think I'll go register over at the SOHC site. I'm sure the guys over there are going to LOVE this....

[Lucien Harpress]

Bought me a battery and started the process of chasing sparks. The starter will turn over if you jump the solenoid, and I found that several contacts in the ignition switch have no continuity, so I've got a replacement one of those in the mail. Handlebar controls (and handlebars) are probably next, but those can wait for the next paycheck.

Started cleaning up the exhaust as well- I think I can make it look better than it currently is, but I managed to open up some holes in them (and they probably won't be the last). I'm in no hurry to replace them, though. Running first, cosmetics later.

[fish]

change the oil before cranking it over a bunch

[Lucien Harpress]

Got my new ignition switch plugged in today, and lo and behold, more works than I would have thought! In no particular order:

-Headlght (Hi beam only, but that's the fault of the light)
-Idiot Lights (Hi, Oil, Neutral)
-Start button (but not solenoid- just clicks. Will spin the starter if you jump the posts.)
and most importantly...
-THE HORN!!!

What sucks is that the control switches that work (the right ones) are the ones that I have to replace, because they won't work with my new carbs.

Oh yeah, new carbs! I managed to get a hold of a clean set of correct K2 carbs plus an airbox, simply for the cost of shipping my carbs to Wisconsin. Not only that, all I need is a set of floats, which are comparable to a rebuild kit anyway.

Forward progress is good progress.

[Lucien Harpress]

Lots of progress since the last update.











I got the exhaust off, which was an experience. Whoever designed that header-to-block connection really dropped the ball. 1968 CT90 header connection? Studs and nuts. 1976 GL1000 header connection? Studs and nuts. 1972 CB750 header connection? Extra header connection, pinch rings, and PHILIPS (JIS?) SCREWS?

Anyway, exhaust is pretty shot. I managed to snag a set in better shape off of ebay (for more than I really wanted to spend, but less than I expected), so I'm hoping I can sell the current set of at least a little bit. But the reason I pulled the exhaust is because the spark plug in cylinder 2 is still stuck, and the only way to get a straight shot at it is to pull the motor. Which is okay, because there's a pretty major oil leak on the front of the engine coming from the head gasket. I'll probably replace that, seeing as how the engine is out.

I also got a new set of bars. They're a bit lower than I expected, but apparently stock for the K2 model. Maybe just the export model, but then again I'm toying with the idea of turning into a Euro version anyway. Or at least close as I can afford.

In any case, progress is progress.

[JSBail]

It seems like like all the early Honda inline 4's have issues with the head gasket leaking oil at the front many times coming from the rubber pucks under the cam holders even after new gaskets and seals are installed. Read as many tips as you can in regards to replacing the head gasket so that way you wont have to worry about it leaking oil for a long time.

[Lucien Harpress]

A bit of a while since I last updated, and while not much has changed on the bike itself, I did get ALL kinds of new presents for this project. First up? New airbox and carbs!



The airbox is from an F model, and the carbs need floats, but the airbox still works, and these are the cleanest carbs I have ever seen. On ANYTHING. In fact, I was so stoked about the airbox, I bolted it up just to see what it looks like.



Yes, I'll need to pull it when I pull the motor. With only two bolts, I don't really care.

Moving on, I also got this box in the mail today. I spent too much on it, but I think it's worth it.







They aren't perfect, and they do have some dents and scrapes (and one hole), but..... compare them to the set I have now. I think I did okay.

Anyway, I hope the next update will be the motor out of the frame. Until then!

[robin1731]

Be careful, those engines are heavy. I put the airbox back on the 750A I got. It is nearly ready for a new owner.

.

[Lucien Harpress]

It's too bad my younger brother is eternally broke. He's been wanting a Hondamatic for a long time. But with the amount of projects he already has (mostly tractor and bicycle related), I think his eyes are bigger than his wallet.

As far as my 750 goes, I'm just glad I'm getting my money's worth out of my engine hoist.