CB750 K0/K1 Hybrid

[Lucien Harpress]

Tell me about it. For the longest time I had a dealer literally 5 minutes from my house ON my road, but they closed up shortly after I bought my first bike. Most of the staff moved to another shop about 25 minutes away, which to their credit is run by an old-timer and have a better than usual chance of having vintage parts in stock. Downside? The owner is a bit of a... less than pleasant man to deal with. Told me that my yellow '76 'Wing was really a '75, and insisted I was wrong about my own bike because (and I quote) "But I was there!" Thankfully he doesn't usually run the counter.

Unfortunately, THEY are closed on Sunday, so I had to take the hour trip to the next city over.

In any case, more progress!



Best I can tell, shift linkage is back together correctly. It seems to work, anyway. I'm looking forward to NOT having to deal with springs for a while.



Normally I'd leave it, but the shift arm is only held in place by the outer cover, so I figured I'd get that on as well. It'll have to come off once I start running wires through it, but that won't be for a while. I also took the time to try to get a better polish on it, because I am a bird and love shiny things.



And finally, I took my first tentative step into my ill-advised quest to obtain a fake K0 model on the cheap (relatively speaking). I managed to snag a '69/'70 oil tank for... what I'm going to call an "affordable" price. Initially I wasn't going to bother, but I've seen K0 sidecovers on a later oil tank, and it doesn't look right. So I bit the bullet.

Goal going forward is to get a set of K0 tins, and I might have figured out a way to build up a set of period correct gauges. That said, I DO plan on keeping some quality of life things that aren't visually obviously wrong for a K0. I'm keeping the later carbs, and the metal chain guard. I may recover the seat, but I see no problem keeping the pan and locking latch. I'll probably end up with something closer to a mash-up of a K0 and a K1, but I'm okay with that.

And, as always, I reserve the right to change my mind at any time for no reason whatsoever.

[Lucien Harpress]

More progress. New APE heavy-duty studs are all ready to go. They actually went in relatively easily- certainly MUCH easier than they came out. I also managed to miss an o-ring in my shift linkage/primary (or secondary) shaft oiler, so that cover had to come off again. I went ahead and hit the polish on it one more time, just for funsies.





Points assembly is back in place. The advance mechanism was a bit gummy, so after taking that apart (ALMOST losing a c-clip to the monster in the floor that eats dropped parts) and giving the moving parts a bit of oil, that now works much better. My points cover is a bit dented, so if I can find one in better shape for dirt cheap I may replace it, but I'm not holding my breath.

[Lucien Harpress]

Another day, more shiny parts.



The stator cover took a bit of extra time, because the corrosion on it was quite a bit worse than on the shifter cover. I still wasn't able to get the top quite as shiny as the rest of it, but I'm okay with the result I got. It's certainly better than I what I started with.

I also dropped my barrels off to get the fin re-welded, then on to the song and dance of getting that cleaned and painted.

[CYBORG]

looking good

[joecoolsuncle]

whats up with this fakebook blogger stuff? you think you gonna own the world? you are an idiot. honda 750 4 was a good bike in da day. it is not a good bike these days. its old junk. you tyin to revive junk by calling it "barn find". next thing we here, is you will call it a bobber. get real.

[cfairweather]

The CB750 was and is an incredible motorcycle. It changed the motorcycle world in the early 70s and today, people still love the way it looks, sounds and rides. It is not junk and you have succeeded in insulting most everyone on this website. Go away if you don't like these classic bikes.

[Rat]

Yes, unacceptable here, sent him a PM.
He will be banned (again?) if he persists …

Gord

[CYBORG]

whats up with this fakebook blogger stuff? you think you gonna own the world? you are an idiot. honda 750 4 was a good bike in da day. it is not a good bike these days. its old junk. you tyin to revive junk by calling it "barn find". next thing we here, is you will call it a bobber. get real.

ahhh...... I have some thoughts but never mind. you wouldn't understand anyway

[Lucien Harpress]

Oh boy. I leave for 5 minutes to attach my neutral switch wire and things get interesting.

...Anyway, speaking of the neutral wire, THAT turned into an adventure. I ran headfirst into that Honda engineering quirk of only having the bare minimum of clearance for everything, and no more. The neutral switch wire has to be snaked between the stator and shifter covers, which DOES have a small gap for it to fit into, but only just. What I thought was going to be a 5 minute job turned into a half hour ordeal of flipping the motor (several times), taking covers on and off (many times) and at one point removing the starter motor.

Good news? It's all sorted, and everything is once again right in the world (for now).

[Lucien Harpress]

Another day, another part that needs shined up.



I'll be honest, I was 100% ready to paint the oil pan and be on with my day. The only reason I left it off this long is that the engine sits on the work stand better with it off. Imagine my surprise when I found out the oil pan (such as it is on a dry-sump engine) was bare aluminum. And when I see bare aluminum on this engine, you know what I have to do.

(Now, I didn't devote as much time to this as, say, the side covers. The ribs made cleaning it up a royal PITA, and for being unable to see most of it, what I ended up with was more than good, I figure. I still need to go back and re-plate a couple of the bolt heads, but that's small potatoes stuff.)

[cfairweather]

Beautiful work.

[Lucien Harpress]

Progress continues, albeit nothing flashy enough for photos. Piston rings have arrived, so once I confirm ring gap I can get the pistons re-installed. I've also finalized all the gasket and locating pins (which turned into a bit of a fiasco), so depending on how long it takes me to clean and paint the cylinder bores, there's a good chance I can get those on before new years.

In the meantime, I've had a bit of a lapse INTO judgement. While I still want to procure some K0 bodywork for this bike, I think it's going to be on a longer timeline than I initially thought. If I didn't have another bike project lined up for 2023 (ie, my Dream), maybe I could justify the expense of what is essentially a color swap. But I'm going to be deep enough money-wise just getting my CB750 completely road-worthy, where getting a body kit isn't worth it right now.

Like I said, I'd still like to get it done. But instead of, say, using my tax return money to help me get there before spring, the new plan is to put away a bit of each paycheck until I can afford it later in the year. I need to get a bit more mileage out of my orange paint anyway.

That said, I'm keeping the smaller early brake light on it, along with everything else (blinkers, grab handle) because I like the look of that better than the wraparound bar. And who knows, maybe a cheap '69 or '70 frame will come up in the meantime and I can do things correctly.

[cfairweather]

I have two CB750 K0 cases but no frame.

[Lucien Harpress]

Yeah, the word "cheap" in "cheap '69 or '70 frame" is doing a HECK of a lot of heavy lifting in this situation. I think the frame I have I got for like 200 bucks, so any replacement would have to be that same ballpark. That being said, I have ZERO problems taking a fully assembled bike, stripping it completely apart, and rebuilding it on another frame. At this point I could probably do it in a weekend. So I can wait until a good deal shows up.

The engine cases I'm currently using are for a '71, which would actually take things much closer to "correct" than I would've ever expected from a bike this loosey-goosey with parts.

[Lucien Harpress]

After a couple days of single digit temps, the weather warmed up enough for my heater to actually accomplish something. So, I got back in the garage to accomplish a bit more on my CB750 engine, to... mixed results.

First up- clutch is officially back in!



Everything seems good, although I won't know for sure until the bike is back together. I've held off on getting the cover on because one, I need to polish it (of course), and two, despite all the work and painting I've done to this block, there are a number of bolt holes I STILL haven't cleaned out. So the dirt the block had been sitting in for a year? Still there. Oh well. We'll get there.

On a slightly more annoying note, I started tackling the bores.



I've seen some baked-on gaskets before, but NOTHING as bad as this. Normally a razor blade and some patience are all I need, but what you see here is about an hour's worth of effort. I've caved, and will probably be buying a can of gasket remover tomorrow.

Ah well. I do this for fun, right?