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So, you are correct. But I did remove all the nuts and bolts before getting the cylinders off. The locating pins on the cylinder were so oxidized that it literally was frozen together. Eventually I got to the point where I could use liquid wrench hoping it would free it and it did. But those...

That’s potentially one of the reasons I had a real hard time removing the head due to the dowel pins being rusty after I got it off and tried to remove the dowels I probably and most definitely bent them a bit probably causing it to not seat properly. Well time to buy new gaskets and new dowel...

I used new oil seals.

I’m going to attempt to fix it. I can’t even think about selling a bike that’s leaking oil. Is there a possibility that I over torqued the head? I torqued it to spec then did a 10+ mile ride to break it in. Let it cool overnight then retorqued it. Like maybe when I re-torqued it could I have...

Lol u fine. My main question is if I remove the head and the cylinders will it cause the rings to not seat properly due to removing the pistons? Because at some point I’ll need to replace the gasket. I’ll probably use a copper spray to help seal the new gasket.

Yes I’m talking about the base gasket.

If I remove the cylinder heads to replace the gasket will it decrease the compression when I put it back together? My thinking is the rings are seated and if I remove the head it will mess up the seal. Are there any ways I can fix the leak without removing the head? I’ve heard of people using...

Still a bit frustrating because it seems you said that you've done multiple bikes with like say a 75/115 set up and had absolutely no problem.

[emoji23] I'm ordering some air boots. Gonna throw her back together with the airbox on and see if that solves my problem.

I guess my question is which jet controls WOT? I have totally rebuilt my 1981 CB750C. I have done the timing and the valve clearances. I have 4into1 delkevic exhaust and individual K&N pod filters. The current jetting I have is a 135 secondary main and a 80 primary main. With 3 turns out on...

Technically it’s 135 secondary and 80 mains.

So......... I have rebuilt the top end and now I have great compression. Jetting is 135 mains and 80 secondary jets. Pulls great all the way to 60 mph and then kinda Boggs a bit. Any ideas? Thanks!

Alrighty then. I’ll degrease the mating surfaces and start assembling.

With no gasket

Okay. Well currently when I put the head on the cylinder no gasket and I put a light on the other side I can see a little light. I’m not sure if the head flexes after you torque it down but I was worried that that could cause some problems. Thanks!

I’m rebuilding the top end on my 1981 CB750C it had a very small head gasket leak so while I’m already in the engine I decided to hone the cylinders and get new rings seeing as it’s low on compression. I’m gonna get the head and cylinders resurfaced to make sure the mating surfaces are flat. But...

I know y’all be mad at me. 😂 so I have the idle jets replaced with #38 and she now idles perfectly at 1100-1500 rpms secondary main is 75 and the main is 120. It idles and revs very response. But right around 6,000-9,000 rpms she boggs a little. But if I turn the choke on she pushes right...

Okay.[emoji1417]

Just checked the compression on cylinder 1 it’s 120-125psi. Looks like I’m gonna do the top end rebuild. More than likely that’s what’s been making my carbs go crazy. Thanks!

Already left ordered them. Size 38. [emoji1692] hoping this solves a lot of it and I also bought 105-110-115-120 main jets.

Oh and don’t forget my custom KZ750 that I built from scratch. And she purrs like a cat. And she pulls super hard. It’s just annoying that the CB750C is giving me such trouble.

Here is my nighthawk and she runs really well. Here is the photo of the bike I’m working on right now

So, I took the carbs off my CB750 nighthawk and put them on my custom and it runs much better. It goes back to idle really well and revs okay still a few bogging spots. But that may be because I had 68 secondary 125 main jets in it. I got guitar string and could make it thought almost all the...

I’m beginning to think it’s compression. The bike ran great earlier with the crazy jet settings but idk why it’s giving me so much trouble. Right now one of the best ways to describe it is the fact that it won’t run unless you keep the choke on. And in fact, with the choke on she idles properly...

I’ll be honest, I haven’t checked compression. Only thing I checked was to see if the valves had any leaks and they were air tight. Or at least I couldn’t hear or feel anything. I just bought a compression gauge kit and I’ll check that next week.

I’ll try the 75 115. But it seems to run better and actually has a higher top speed with a bigger jet. But I’ll give it a shot

Lol it idles much better now around 1700rpms But still has very random high idle I’m talking up to 7000+rpms

Let’s scratch everything. I have 4 into 1 delkevic and K&N pods. What jetting should I use? I have 130 mains and 75 secondary. It gets up to 80mph but seems to be maxing out. Any ideas? It isles much better but won’t hold a steady idle.

Uggggg. I’m so freakin frustrated. I thought that it was the fact the I had the jets backwards. But after I turned them around. Same problems as b4. High idle amongst other things. So what’s wrong? I feel like I’ve covered all my bases. So rn I have 115 mains and 75 secondary’s. No shims on...

U good bro! Just glad we have people like you to help me think things though and explore every possibility. You a boss bro. When I get everything set properly I’ll let you know how it goes