1974 CB360 Engine Troubles (I think)

Good news!

Today I decided to go through the timing adjustment and carb sync (for the 4th time ) but this time I guess I did it right, because I can go faster than 30 mph now lol

But there are still some problems with it. Occasionally, when I pull the throttle quickly, there is some white smoke coming from the right muffler. I don't see it when I ride normally, only on those quick blips.

The only other issue I noticed was when im slowing down to a stop, the bike dies. Is this an electrical issue?

Also, when I did the timing adjustment, I noticed the right point contact plate isn't flat, like its worn more on one side.
 
It's more than likely a carb issue.
With stock airbox plus 'paper' filters, (even 'reconditioned' seem to work) the exhaust doesn't seem to matter (it does lean out with short systems requiring 'over size secondary main jets)
The stock carbs cannot simply be up jetted without various modifications if you fit K&N or Uni filters. Cheap 'pods' cause all sorts of issues, main problem is restricted airflow somewhere after 6~7,000 rpm.
You have 'second generation' 3 jet carbs, really the last ones that could be modified relatively easy.
A couple of people have found setting, parts and pieces that work for their set up
As for one set of points 'wearing' more than the other, pretty normal event, particularly if ignition has been left on when one side points are closed (this can also heat return spring enough to cause miss-firing at lower rpm (generally around 5,000 up)
 
crazypj said:
It's more than likely a carb issue.
With stock airbox plus 'paper' filters, (even 'reconditioned' seem to work) the exhaust doesn't seem to matter (it does lean out with short systems requiring 'over size secondary main jets)
The stock carbs cannot simply be up jetted without various modifications if you fit K&N or Uni filters. Cheap 'pods' cause all sorts of issues, main problem is restricted airflow somewhere after 6~7,000 rpm.

So I currently have the stock filters and stock mufflers on. Are there any other modifications the PO could have made that's causing the white smoke? Not sure if this matters, but on the right muffler air leaks from a few places.
 
Once set correctly carb sync shouldnt change. As long as lock nut remains locked.

Did you get your battery replaced, charging system working properly AND timing set with a timing light?

As long as points are gapped to spec. and clean. They should be fine. Unless as PJ said. The spring has been compromised due to overheating.

Not sure about white smoke unless youve got a cracked or poorly seated valve. (blue smoke)
Maybe steam from water condensation evaporating out of the muffler???

(white) smoke is usually seen coming from vent tube in the head cover. (Steam) due to water condensation in the oil.

Dying on decel is most likely a lean condition. You need to adj A/F mix or have dirty jetting, OR vacuum leaks.
 
If you want to make any change, mufflers or filter setup.
I recommend sending your carbs to crazypj for proper modifications and overhaul.

But before doing that you really need to de-bug her first. By getting everything set up to run decent and reliable.

A lot of times Electrical issues can "look" like carb problems, and, Carb issues can appear as electrical.
If you start making changes before solving problems they tend to snowball. And you end up chasing your tail.
Wasting time and money.

Just make sure one system is correct, then move on to the next.
 
One of the very first things I do on my bikes is go through and clean EVERY single electrical connector.

From headlight bucket to tail light to bar controls to neutral switch and every one in between.

It takes some cussing a few hours. But once its done its done. And can eliminate a myriad of troublesome issues upfront.

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trek97 said:
A lot of times Electrical issues can "look" like carb problems, and, Carb issues can appear as electrical.
If you start making changes before solving problems they tend to snowball. And you end up chasing your tail.
Wasting time and money.

Alright so I'll leave the engine/carbs alone for now and focus on the electrical since thats where it seems things are tripping up.

I'm definitely going to go through and clean all the cables and connectors to eliminate any issues there, and I definitely need a new battery as 48 hours of charging it did nothing for it. I'm planning on getting an AGM battery but I'm not sure how much CCA I need. I read some people saying 140 should be enough, but the on AutoZone the only batteries labeled as "12ah" had a CCA of 200 or higher.
 
If you plan on keeping the stock battery box in its stock location. Just get an agm that fits it properly.
8 - 12ah will give you what you need.
 
trek97 said:
If you plan on keeping the stock battery box in its stock location. Just get an agm that fits it properly.
8 - 12ah will give you what you need.
But none of the AGM batteries I've seen show an "ah" value, only volts and CCA. I was wondering what is the CCA equivalent to 12 ah
 
Your sure the 'white smoke' is actually smoke and not just water vapor as engine heats up?
With CCA, more is better as it gives a reserve. You only need about 35~40 amps to keep engine turning over and around 60~70 'spike' amps to get everything initially moving. 140 CCA in theory gives you 2 ~3 starts (it's actually higher number)
Just find the exterior dimensions you want and see what CCA it has. The battery number usually tells you the A/Hr (eg, BS12, YB14, etc)
 
crazypj said:
Your sure the 'white smoke' is actually smoke and not just water vapor as engine heats up?

Well the smoke comes regardless of how hot the engine is. It only smokes when I'm revving the bike in idle, otherwise I'm not seeing any smoke when I'm riding (even at high rpms).

I'm afraid it could be oil smoke, but it doesn't smell like that and the smoke doesn't have any blue/grey tints to it.
 
trek97 said:
Its the color of burning money. ;)
Oh man this project has doubled the total cost of my bike, not to mention all the govt fees and taxes

Serious question tho: do you mean that the smoke is just my gas burning up, or that the engine is going to need more work?
 
Just leave it alone until you get it running consistently then 'we' can start doing various tests
 
First I want to say thinks to everyone so far, it's been a really exciting/sad/expensive time but I've enjoyed every second of it!

So I replaced the dead battery and rectifier/regulator (the old regulator was rusted out)

I also finally got a tach and noticed that my idle was only at like 800rpm. So I synced the carbs again and it no longer dies while decelerating! ( I'm such an idiot )

Also checked to timing with the strobe light and it was within the specs.

So this is what's going on:
- still the smoke from the right muffler, only when I rev while idling (from 2krpm and up)
- the left muffler is just a bit hotter (like < 5° F)
- it feels "weird" in the lower rpms, like a low growling noise, compared to 3k -5k
 
You now need to vacuum sync carbs and run it for at least 200 miles. If it's had a problem for a while you may just be heating up combustion chamber, exhaust port, pipe and silencer then burning out any crap that's built up.
Keep an eye on oil level and run it for a while (pretty much check oil level every 50~60 miles or every time you ride it if doing less)
Idle adjuster is kinda 'hidden' behind clutch cable at front of left carb
 
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