CB360 - timing : loud POP

R

renslow

Been Around the Block
So long story short. I've read about this issue with trying to get an old twin started with a huge BANG and thats it and im very certain that im not 180 degrees off. I'll give some details to see if anyone can help me with this issue.

I've started my timing by setting both of the points to .014 gap. The left side timing mark is adjusted by moving the timing plate and this is at the LF indicator on the stator. I've set the right side point by adjusting the points arm accordingly to the F mark. When i hit the test light on the points it's DEAD on. For the left cylinder and the right cylinder. I've noticed when the right cylinders points match the F indicator on the stator my points arent actually opened at all. Even though the test light turns on?

How am I suppose to 'readjust' the timing when it's already timed correctly? The left side point gap is perfect but for some reason the right side point gap isn't opening up it seems like.
 
Are you using the official Honda workshop manual according to procedure?
 
I do have the manual as reference. I did do some searching on the forums and I believe I did set the timing wrong. What's the trick to make sure it's on a compression stroke? I thought setting my finger over the spark plug hole and feeling the cylinder compress with air was the trick when setting that LF for instance
 
When you see the intake valve opening, the next TDC is the compression stroke.

Also, manual is good but the best instructions I've followed are these written by Steve over at hondatwins.net: http://www.hondatwins.net/forum/viewtopic.php?f=46&t=24549
 
There will be a notch in the points plate the corresponds to a notch in the head so that you know things are aligned. The notch won't always be exactly aligned because you need to move the plate to time the bike, but it should be pretty close.

The loud pop is almost definitely a sign the timing is 180° out. It will be very loud. Like a gunshot.
 

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Ah, yes like a gunshot. My points plate is rotated ccw comparing the picture you just posted as reference. This is clearly the issue! I appreciate the help. Once the rain stops I'll be sure to get this thing going again.
 
HerrDeacon said:
When you see the intake valve opening, the next TDC is the compression stroke.

Also, manual is good but the best instructions I've followed are these written by Steve over at hondatwins.net: http://www.hondatwins.net/forum/viewtopic.php?f=46&t=24549
Click to expand...


When this tappet goes down all the way and then starts to lift, then watch for alignment of the index mark. In this position of the piston in the left cylinder this should be TDC on the compression stroke aka wont both of the valves be closed?

So compression stroke is when both valves are closed correct? If so, will i be able to see the valves at all through the sparkplug hole? or should I just take the tappet covers off. I'm sorry I am trying to imagine this in my head without having the bike in front of me and im not sure if im just confusing myself more.


So since I'm 180 degrees off when i go to check the timing should my exhaust valve be wide open? Or is it the intake valve wide open? (As of how the bike is sitting right now prior to fixing the issue)


I think once these questions are answered i should be prime.

This is my second 360 i've rebuilt and i thought i had the timing problems down but i guess i just got lucky when i was timing the last bike. :)
 
Yes, take the tappet cover off. When you see the intake valve opening this is when the cylinder going down and drawing in the air/fuel mixture, so then on the subsequent up swing of the piston both valves will be closed and at the top will be TDC compression. Both valve tappets (intake and exhaust) on that particular cylinder should be loose (should be able to wiggle them).
 
Ah so that's how an engine works :)

These articles you posted are a huge help I bookmarked them right away. I think I got it down and AGAIN I appreciate the knowledge being shared here trek and herrdeacon.
 
Your welcome. I have thought about improving that ignition timing post. maybe this winter...

brown_posterjpg_thumb_zps2bc29e58.png
 
Hey that would be pretty sweet. I may add some pictures to this post when i get time to fix this problem of 180 degree problem. Incase some members search the forum they can find a good picture-to-picture processes on fixing the issue rather than making a new post. If ya catch my drift.
 
May sound stupid.....but
When I timed my engine the first few times, I just took out the plugs and watched the valves to make sure I had things exploding at the right time. It really helped me feel good about what I was doing...and my understanding of the engine improved 10 fold. The valves will clearly present themselves, as will the cylinder head....use a flashlight if you need to. (as you can tell I am a visual type person)
 
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