Timing gun questions

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Yamaboy

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I just hooked up my timing gun, and I do believe I'm off. The green line indicates the mark shows up while in lower rpm (sorry, I don't run a tachometer, so I'm guessing where 1200rpm is) and the red line indicates it at higher rpm (3200 rpm?)

Does this mean I need to retard it or advance it?
Also, should the mark match the firing mark or TDC mark?

I also took a pic of my points. I have figured out the 2 screws to loosen and where to adjust, but which way do I twist in order to advance/retard?

Thanks in advance
 

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I can't answer first ? as I did the timing on my since sold tracker several years ago and forgot now. To advance the timing rotate the points Plate counter clock wise. Retard rotate the points Plate clock wise
 
Thanks racerdave! I probably could have figured it out just by turning it, but I wanted to be sure.

Still need to find out if I'm too advanced, which I'm leaning towards, and what marks to match...firing mark is my guess, but would have liked to be sure
 
Yes, your timing is off. It's too far advanced. It appears you have a later motor that originally had an electronic ignition and it has been converted to points. Those later motors don't have all the timing marks like the earlier points models did because their timing was not adjustable. They only have a mark or "range" for the idle timing. It should fall somewhere in that little "U" shaped bracket to the left of the "T" mark .....

IdleTiming.jpg


Even though there is no full advance mark, we have figured out it should be in line with the left side of the drain notch at the bottom of the case .....

Advance.jpg
 
THANK YOU, 5twins! That helps a lot. I have been messing around with the gun...it does seam like I have misfiring problem on my left. I hook it up to the left wire and the light works sporadic...according to the gun manual it could be due to misfiring...which could be due to me trying to gap that point...

Would you happen to know how to find TDC on my set up?
 
I actually knew that, 5twins:)...it is just that when I have tried to rotate (anticlockwise) by hand (spark plugs out) I could never get them to line up...the mark would just swoosh by...maybe because it was too advance? I will try to set the timing tomorrow. I did it roughly today...as I said I don't have a tachometer...just running a speedo in the middle.

Also...I don't know if this is just my bike, but in order to retard, I actually had to push the adjustment points downwards...which should mean anti clockwise.

And I do have a misfire every now and then...it became clear when I used the gun. Do you think a larger spark plug gap could sort it out?

Come to think about it...could a leaky exhaust pipe gasket cause the misfiring?
 
To hold the rotor to keep it from passing TDC use a wrench. Box end or open end. That is another 5twins tip.
 
THANK YOU, 5twins and weekendrider! She is running strong again. Great info put to good use...when the timing mark came around, I just swapped over to a flat wrench and held the TDC...kind of embarrassing not thinking about myself...makes a ton of sense...but hey, when stressed out I don't always think straight...:thumbsup::bike:
 
Watch the points if you see large or constant arcing it's a sign a condenser has gone bad , this is a frequent points problem.
 
Thanks, gggGary!
My upper point sparks every now and then, but the sparks are not too bad. I have already placed an order for an ignition kit w/ new condenser and points. My points seams to bee in good shape...I cleaned them and checked for pitting...I will just keep the new ones as a back up.

Weekendrider, I beat you to it...confused and stressed out. Trust me, when I found the loose parts and broken atu backplate...can you say panick/shocked...not a good feeling.

Have a nice weekend, guys!
:thumbsup::bike:
 
The reason the engine won't stay at TDC is the valves. As the engine turns the cam opens the valves. Valve spring pressure holds the cam lobe back.
When the high point on the cam lobe goes past the point the valve is fully open the spring pressure pushes the cam forward.
This rotates the engine past TDC.
I use a socket and breaker bar to turn the crank. That way I can stop the engine at TDC.
But for most things TDC isn't really needed. Valve adjustment can be done at most any point the valve is closed. Sorta the same with points, anytime the points are open.
The base circle of the lobes cover a fairly wide angle of rotation.
Leo
 
Watch out for timing lights with an "advance" dial, make sure it's set to zero.
 
I was just rereading this thread and saw that you have a erratic flashes when you hook the timing light to the left side. Try turning the clamp over. A lot of timing lights work best when the spark is traveling in one direction, like from the coil to the plug. If the spark is traveling the other way as in from plug to coil, it won't read the spark as well.
Leo
 
Thanks, racerdave!
What kind of grease? The whitish/yellowish kind (looks like petroleum jelly), or could I use Coastal (black) universal grease? The coastal universal is thinner...probably not a good idea...

Thanks, gggGary! I have an old craftsman gun...doesn't have "advance" dial.

Thanks, xsLeo! I believe you are right about the TDC not being absolutely necessary when adjusting valves...before 5twins and weekendrider told me about the advance markings on my rotor and to use a flat wrench to get it to TDC, I had already set the valves by placing my thumb over the spark plug hole to find the piston on the up/compression stroke...then I would just turn the motor w/ very small increments and measure the gap...I would do this several times in order to find the biggest gap and adjust at that point....I used the same method when adjusting the point.
From reading other post about TDC...when the lines match up at the rotor/TDC mark...that is not the actual true TDC anyway...

As for the timing gun not always flashing...from researching internet, other post and the timing gun manual...it could be caused by "faulty" spark plug or/ bad condenser. I will retest when I get the new condenser installed.

HOWEVER, I do have a request...next time you guys are out enjoying your bike, could you please make a note how fast/mph you are going at 3500rpm...as I have stated before, I'm running speedo only...not ideal when trying to use a timing gun:doh:
As always, much appreciated guys:thumbsup:
 
Last edited:
TwoManyXS1Bs, you are awesome...thanks for the link...you really got it figured out. Guess who will be running around 52mph...a lot...I just need to figure out what the engine sounds like approx. 3500rpm in order to set full advance.
Good man!:thumbsup:
 

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