79 CB750K New here

[Ba5sKing]

Time for re-assembly













Cracked Alternator Cover, apparently not properly torqued bolts will back, very fast.





Best friend helping me with the build

[Ba5sKing]

New blinker




Tank back on with my friends old night hawk seat, no customization needed! just got longer bolts that hold the rear plastic with the brake light and the two mounts on the nighthawk seat fit perfectly with the correct seat position! there is alittle bit of a gap between the bottom of the seat pan and the plastic but im not a perfectionist


Shiny thanks for shiny gauge cluster :D


Viper cafe fairing. Barely has clearance with these bars, but it does! Well without a stock master cyl, I am using a cbr1000 master cyl currently. Eventually looking to put either Goldwing forks or a cbr1000 front end this winter. Want dual rotors on the front end for my bike but thats for the future.

[Ba5sKing]

Bleeder screw seized on my original caliper, so bought a seized caliper off ebay and rebuilt them. basically just used a giant vice and pb blaster to bottom it out(compress the piston). threw it on the hydraulic system on the bike and bled it and compressed with just a hand clamp for about an hour and some of going back and forth it finally unseized itself.






First Rear end test with the girl. no seat, no front brakes. rear brakes work fantastic and carbs and everything were re mounted and at the time seemed to be working well. Immediately went to break the bike in after the front brakes went in with a 2 hour ride to formula drift even in NJ.

She likes camping

[Ba5sKing]

So here is whats going now, rode it for almost a month, running STUPID rich. Like 15mpg rich, not kidding. Went to a bbq and the bike had 0 power for acceleration. It was borderline dangerous and brought the bike back to the garage. The bike was getting very hot and the idle would not come down from 3.5 grand. Even if i adjusted the quick idle setting screw

What Ive done so far:

Pulled the carbs re set the pilots, they were out at very different turns, and all of them over 2.
So I set them all two the 1-1/2 turn recommended by the manual, and their solid tip fuel screws(sorry if my terminology is incorrect PLEASE call me out on it, i need to learn how to tune!)

Took the bike out to get it to temp. Idles nicely. Falls on its face HARD when it hits about 5 grand. Tried the manuals suggestion for tuning the fuel(air/fuel?) screws. found it difficult to accomplish, and set them all 2 turns out. felt a little bit better, but rolling off the throttle causes back fire and still no power over 5 grand, it will slowly hit redline, but its painful for both the bike and I to get there.

Attempted to tune the pilots by ear. No back fire coming off the throttle or quick spurts of throttle when at idle, when on the center stand in neutral. Took it for a ride, seemed good...up until around 5 grand once again. Once it warmed up idle increased by about 1000 rpm and dies if left on idle. I thought about maybe tuning it again, thinking I had tuned it too cold, when I looked at the carbs so I saw fuel boiling off the trans. Its leaking out of this funny output from the carbs ONLY when the carbs are hot.

I know these carbs do not leak cold, I have pulled them and left them connected to the tank for hours with no leaks. Kind of noticing that there is a flange on this plastic output thing. and I think that the fuel is leaking out of this opening.

Here is a picture of the same type of carbs I have (found online). can you guys identify where that thing inbetween carbs 2 and 3 is, what its for, and where it should go to? and if this could be my sole problem!


I believe where that rubber hose ends is what I am talking about...especially since I have no hose there in my carbs at this time.

[TOOLS1]

Very COOL! Your running problem is being caused by a bad vacuum leak. It gets worse as the engine warms up, because the rubber intake boots are heating up, and expanding.
TOOLS

[Ba5sKing]

Hey tools!

Glad you like how the build is coming along, does the terminology 'running problem' talk about my top end issues or the fuel spilling onto the trans? I think your talking about the top end issue, but I just want to be sure!!

Thanks for everyones help! I give this forum much credit when anyone asks how I got it done.

~Ba5sKing

[TOOLS1]

The vacuum leak is the source of your running problems. The leaking fuel is because the needle valves are not sealing. Could be dirt, bad needle tip/seat, or heavy float. That thing between the two carbs is a vacuum port for the automatic petcock (SOS).
TOOLS

[Ba5sKing]

Hey guys,

I tested for a vacuum leak by spraying brake cleaner over my boots while the bike was running, and this caused nothing to happen. No up or down in idle. However, I think I should probably connect that vacuum port to, well anything, right now it is open to atmosphere. I noticed on the middle rear side of my airbox there is another port that I have nothing hooked up to. Is this where I should connect the auto-petcock to?

I am also on the fence of either cleaning the circuitry that leads to the top of the diaphram that helps open up the main jet when at full idle to possibly cure this symptom, or just start all over and get new gaskets for everything and by a ultrasonic machine from harbor freight.

Let me know what anyone thinks!

[TOOLS1]

That open vacuum port is a severe vacuum leak. You need to get some rubber vacuum caps, (any auto parts has them) and put one on the open port.
TOOLS

[Ba5sKing]

i should just get a tools sticker and throw that on my tank, hahah feel like you been building my bike with me ;) ill post on here how the bike behaves once i cap it.

[Ba5sKing]

So I capped the vacuum port, and the bike seems to behave slightly differently. However I am still not doing well at top end. One of my friends noticed that one of my exhaust outlets isnt quite as hot as the other 3, so I am thinking something is wrong with the spark wire/plug. Which makes sense that a 3 cylinder motor would have less top end then a 4 cyl. hopefully this is it!