Honda Twins banner

1 - 13 of 13 Posts

·
Registered
Joined
·
54 Posts
Discussion Starter · #1 ·
So I’ve spent the last 2 hours trying to setup my static ignition timing. Set the points on the left point to .014. Rotated the base plate so that the test light comes on at LF mark on compression stroke. I noticed that the right point is wide open. That can’t be right - right?

I’ve been chasing the possibility that cam is out 180 degrees. Everything checks out correct. When 286 is at 12:00 - the mark on the outer ring is at 7:00.

Am I doing it all wrong?
 

·
Registered
Joined
·
1,364 Posts
Year make and model would help...
Did this run prior? Or is this after a rebuild?
The more information you provide, the better your chances for success..
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #3 ·
Sorry - 72 CB350. It did idle but I had a hanging idle above 3k rpm. I recently purchased the bike and have only idled on the center stand. I decided to go through maintenance first - cam chain adjusted, valve lash adjusted, and now I'm on the ignition portion. I was working on the bike another few hours and I also watched a few video. I realized that I was not rotating the engine a full 180 degrees after timing the left point and moving on to the F. I've now called it a night, just need to get the right point timed. I'm not sure if I was having all this difficulty because the points are maybe worn out and I need to just purchase a new point set.

I think I kept second guessing the cam was out 180 degrees out because you never know if the PO screwed something up or it's you that's making a mistake.
 

·
Premium Member
Joined
·
3,006 Posts
How are you measuring the Closed to Open transition?

For static it is usually done with a Test Light Bulb clipped one side to the moveable contact the other to ground.

When the Points are Closed and the Light is ON the Coils are Charging.
The Light will go OUT when the Points Open that is where the Coils discharge and generate spark.
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #5 ·
Yendor, I am measuring the point contact opening by grounding to engine and using the metal flexible strip that goes from the point to the terminal for each side for the test light. I’m assuming when the light goes on - the contact point opens.

Where I’ve seen some discrepancies is on the right compression stroke when the F is aligned with mark. That is 180 degrees out from the left compression stroke right? Common motors says to rotate 180 after timing the left side. Motorcycle nuts video just rotates to F after timing the left side - which is like maybe 45 degrees out. I just wanted to make sure I’m performing this correctly. Thanks!
 

·
Premium Member
Joined
·
3,006 Posts
When you set the gap on the left points, you should do it when the points are at their widest opening
(the "follower" is on the highest "bump section" on the breaker cam of the advance unit)
Lock the left point screws down to keep it at the .014 gap on the plate
Then, with crankshaft now rotated and held on the LF index during the left compression stroke, rotate the entire plate to get the left points to just open (light the light) and lock down the plate
The plate MUST remain where it now is, no further adjustments are made to the plate
Rotate engine to the F index of the right compression stroke
Set right points to just break Open and the Light come "ON".
Lock the right points down.
Now you check the right points gap by rotating the engine until its follower is on the biggest bump
If it is anywhere within the spec range, you are done.
Don't adjust the right gap (or anything else) further.
Gaps do NOT have to be any certain amount or even, just within the spec range.
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #7 ·
Yendor, I’ve read and followed those directions. The confusion is “ right compression stroke “ to a novice like myself, I assumed that rotating to F after setting the left side was correct. I assumed since I’m on the left compression stroke already that rotating a little more to F was still on the “ compression stroke cycle” for both.

After watching more videos and researching - I think if I understand it that the left and rights compression stroke is separated by 180 degrees?so after setting the LF on compression stroke, I need to rotate the engine 180 degrees to be on the right compression stroke? This is where I am very confused about and searches haven’t given me a definitive answer. Thanks for your help!
 

·
Registered
Joined
·
866 Posts
Pull the plug put thumb over the hole it will push the air out on the compression. Or put a light u will see the piston come up.
 

·
Registered
Joined
·
54 Posts
Discussion Starter · #9 ·
Thanks Crashoverride! I didn’t know that the piston top can be felt on the compression stroke. That helps a lot!
 

·
Registered
Joined
·
1,364 Posts
^^^^ I know this sounds stupid... do a search on youtube. ^^^^
You would be AMAZED of all information you can locate..,
 

·
Registered
Joined
·
2,475 Posts
The CB350 is not a 180* firing order engine. It is 45* One piston up the other down. Not both up/down like a 180* engine. So one set of points could still be open as the other opens. Just set the timing at the marks.
TOOLS
 

·
Registered
Joined
·
12 Posts
I'm new to this forum and I'm self thought but this is how I time a 350. Set the point plate so the gap is centered in the slot upper right and tighten, not to be moved again. Put test light on left points spring and ground. Roll engine over to LF, if it will stop at LF it is at split overlap and you need to roll it 360 degrees to fire. You'll know this is right as you have to block and hold the engine in this position. With switch on move the left point until the light just blinks off. Then switch to right spring and rotate to F. The engine will no move by itself in this position. Set point to just blink off. Rotate the engine through both cycles to recheck. High rpm idle is most likely carbs.
 
1 - 13 of 13 Posts
Top