1974 CB360 Engine Troubles (I think)

rsjudka said:
Hey guys sorry for being so inactive but I was bust with school (projects and midterms and such)

I was checking the vacuum pressure of each of my carbs and they are a bit of sync (26 left 30 right) so I'm going to need to sync that up, but I just got stock mufflers for the bike but there is a pinhead sized hole in one of them. Will this hole cause any problems? Or is there an easy way to patch it up? Also is there some safe way to remove surface rust from the pipes?

I also noticed a drilled hole in the right side, is that supposed to be there?

That isn't enough to make a difference, Honda say within 5mm mercury is fine ( I`ve found 2mm woks better and doesn't take too long
 
crazypj said:
That isn't enough to make a difference, Honda say within 5mm mercury is fine ( I`ve found 2mm woks better and doesn't take too long
Thanks for telling me because I really hate syncing lol (not so much with the adjustments more so with the prep to be able to reach the sync screw lol)
 
With the weather getting colder and whatnot, is there anything special I need to do to be able to store it? I'll be keeping it in my garage. I read some people saying to drain the carbs and tank and to remove the battery, but someone also once told me to just leave everything as is and just run the bike for a few minutes every couple of weeks.
 
It's too easy to forget to run bike every few weeks so best bet is drain carbs, remove plugs and squirt some oil down bores (turn motor over a few times then replace plugs) Some say to lower tyre pressures but unless you can get both wheels off the ground I think it's best to increase tyre pressures to 40psi (helps prevent flat spots)
 
Yet guys I have a bit of a problem again... My bike starts up fine and rides good, but my kick starter isn't working I didn't remove it once when I did an oil change, but it still worked after that so I don't think I did anything wrong there. It feels like I can push down all the way without any friction.
 
This same sort of thing happened w Bromz and his CJ360.
Turned out Jesus clip #39 failed and popped off the shaft. Allowing spring #19 to push ratchet #20 away from pinion gear #18.

To replace the clip, you will have to pull the engine out of the frame.

Im not 100% sure but there may be a way to simply pull the bottom case off without completely tearing down engine.
My only real concern would be the cam chain slipper, guides, springs and tensioner arm. staying put where they need to be.

All this may sound a little daunting. But in reality, its not all that bad a job. And you got all winter.

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Check the clutch adjustment before you take anything apart. I've had this happen and it was just the clutch not being fully disengaged.
 
I had a similar issue on a CB360t that is used to have. The float in the right side carb was screwed up. Like the tang was broken off for the float needle. But the right side pipe would get really hot, like it was running super lean. You’re saying that it’s cold/warm points in the direction of an ignition issue, paired with the blue/white smoke being more than likely un burnt fuel. Definitely get to the bottom of it, because that fuel will eventually wash the cylinder walls down and then bad things happen.


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millermatic187 said:
I had a similar issue on a CB360t that is used to have. The float in the right side carb was screwed up. Like the tang was broken off for the float needle. But the right side pipe would get really hot, like it was running super lean. You’re saying that it’s cold/warm points in the direction of an ignition issue, paired with the blue/white smoke being more than likely un burnt fuel. Definitely get to the bottom of it, because that fuel will eventually wash the cylinder walls down and then bad things happen.

If the tang was broke off float, the needle would drop down and never close. This would cause fuel level to rise, dumping entire contents of fuel tank onto the ground through the overflow tube.
The bike would run rich, blowing black smoke (un-burnt) fuel. The pipe would be cooler temperature.
But yes, an overly rich condition can wash cylinder walls.
 
trek97 said:
If the tang was broke off float, the needle would drop down and never close. This would cause fuel level to rise, dumping entire contents of fuel tank onto the ground through the overflow tube.
The bike would run rich, blowing black smoke (un-burnt) fuel. The pipe would be cooler temperature.
But yes, an overly rich condition can wash cylinder walls.

If the needle dropped down.....in my case it was stuck. But anyways, his issue isn’t with it running rich, it’s getting it to light initially. Removing the one plug wire doesn’t change anything. He said after letting it run, the right side is warm, while the left side is hot like it’s supposed to be Which is more than likely heat transfer from the other cylinder. But after riding it for a few minutes it runs fine. Like a bad condenser, or a set of points that are set too wide, where you need more current to light the candle. My suggestion is to start with the simple stuff. Fresh plugs, set the valves, cam chain tension, maybe a set of spark plug boots. But if that doesn’t cure it, and you have to dive in deeper (coils,points) throw that crap out and step into the 21st century with a modern ignition. 40 years is a long time for Japanese electrical components.


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millermatic187 said:
If the needle dropped down.....in my case it was stuck. But anyways, his issue isn’t with it running rich, it’s getting it to light initially. Removing the one plug wire doesn’t change anything. He said after letting it run, the right side is warm, while the left side is hot like it’s supposed to be Which is more than likely heat transfer from the other cylinder. But after riding it for a few minutes it runs fine. Like a bad condenser, or a set of points that are set too wide, where you need more current to light the candle. My suggestion is to start with the simple stuff. Fresh plugs, set the valves, cam chain tension, maybe a set of spark plug boots. But if that doesn’t cure it, and you have to dive in deeper (coils,points) throw that crap out and step into the 21st century with a modern ignition. 40 years is a long time for Japanese electrical components.

+1 bro. I didn't understand from your story, your experience involved a stuck needle.
Personally, I like points ignition. In my experience, given just a minimal amount of maintenance, they serve they're purpose quite well.
Until the issue is revealed, I feel theres no reason to recommend a guy just simply start throwing money at it. New points are like $20, and At $300+ or -?? Solid state ignitions aint cheap for some of us.
 
Weather is warming up and feel like I finally have her in a decent state. Got the original mufflers on and I gotta say it looks and sounds alot better now.

Thanks everyone for all your help! If anything goes wrong and I get stuck, I'll definitely be back here
 

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I have have spoken too soon...

Just got done with the regular maintenance (cam chain, valves, etc) and I'm kind of confused.

So the bike sounds better (quieter engine), get to higher speeds faster, and the bike has no problem getting to 9k rpms (before it maxed out at 7k). But, the bike takes a while to "warm up" and compression is around 130ish both sides.

I would assume lower compression means lower max rpms? Could the low compression be because my valve adjustments are too loose?
 
Lower compression is leaky valves or worn rings. If your tappets are adjusted too tight, it's possible they aren't closing all the way. Although 130 is not super bad. It's not as good as 160, but it's not as bad as 90.
 
irk miller said:
Although 130 is not super bad. It's not as good as 160, but it's not as bad as 90.

Does it make sense that I have lower compression but the bike accelerates and has a higher max rpm than before? Or are the two unrelated?



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Compression is certainly related to power. Though, I would expect lower compression to reduce hp not gain.
 
It can be related, yes. If you have your cam timing off by a tooth, you may notice decreased compression at low RPMs, but the power band would be moved further up the range. This may seem like a good thing, but it's not. You might be putting your exhaust valves at risk of contact with the pistons. I would consider pulling the rocker cover (remember to reset valve lash every time the rocker cover comes off) and double-checking that your valve timing is correct.
 
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