Different Timing readings on left and right cylinders?

XS650D

XS650D

XS650 Junkie
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I decided to check the Timing before the season begins.Actually I gave the bike to my son (his first bike) I got a new w800 !!
Anyways was showing him how to check the timing with my timing light. Bikes a 77D with electronic Ignition, stock advance.
We tested with the timing light and attached the spark plug wire connector thing, not sure the name and im getting different readings.
Yes I have the arrow on the connector going the correct way lol
Its a fairly substantial difference. Is there a certain side that I should hook to? If I attach to right side plug wire and set timing to
right side of T and I then reattach to left side plug wire the timing will be at the left side of T almost on the line to the left .And at full advance
it will be slightly over advanced by a few degrees. Am I good to go. Any advise would make me sleep better .Thx
 
77 D did not have stock factory electronic ignition so info on what setup can help
With points there is an adjustment possibility in this sense on the backplate
 
XS650D said:
I thought I added that info above, Its not stock obviously,i added or changed to Electronic Ignition few years ago.
No points .
Click to expand...
There exists a whole bunch of electronic ignitions 5 - 8 - 10 some of them uses the stock advance others not
Different triggers optical and magnetic
No Pictures and no Specs .. ? Dificult for anyone even if had the same problem here on the forum.
 
Yes, on a single coil with two outputs (two plug wires), the power flows in one plug wire and out the other. So, you would want that arrow on your light to point one way on one wire, the other way on the other wire.

Honestly, this is something I don't think I ever tried. I always just clip the light on the left plug wire because it's easier, lol. Maybe I should check both, lol.
 
XS650D said:
If I attach to right side plug wire and set timing to
right side of T and I then reattach to left side plug wire the timing will be at the left side of T almost on the line to the left
Click to expand...
I don't rightly see how that's possible with a dual output coil. :umm:
You have one coil firing both plugs from one trigger signal every 360°
When the coil secondary collapses and discharges across the plugs, it's firing both at exactly the same time.... from the same discharge pulse. They can't "not" be identical. At least not enough to ever see with a timing light and 1500rpm. You might get a 1 or 2 millisecond difference, but you'd need to be up in the hundreds of thousands of rpm's to have any hope of seeing that.
Faulty timing light maybe? Although I don't know how it would know one side from the other?
 
Last edited:
Ok so a positive side and negative side. The left side at least on my bike is really jumpy and really hard to set at idle.
Easier if I idle up to check full advance. The right side seems way more stable. There is definitely a difference in
sides though. I Ohm checked from from one spark plug cap to other and got over 24k. So that sound about rite.
Im checking the net on old posts.I vaguely recall PAMCO Pete talking about this . Pretty sure my Timing light is working correctly.
I checked that I have it zeroed out as mines adjustable. 5T that may be the reason but which side do I have the arrow on which cylinder?
 
I don't know. I'd try it both ways on each cylinder, see if any match each other.
 
Jim said:
You have one coil firing both plugs from one trigger signal every 360°
Click to expand...
Maybe I'm onto something totally different, but here goes:
The Pamco has two triggers. I'm pretty sure the XScharge ignition also has two triggers. The slightest error in the positioning of those two triggers on the plate in relationship to each other means that the timing of each side will be different. Even normal slop of the trigger assembly on the advance rod will result in trigger positioning inconsistencies.
Every single Pamco I have ever installed (maybe a dozen), has had timing signal discrepancies, but it manifests itself differently from what XS650D described. What I get, is TWO slightly faint timing light marks when I use my timing light gun instead of one bright mark. What I am seeing is that slight difference in the trigger positions, in relationship to each other, on the trigger disc. Hope that makes sense. The physical distance between the two marks is always about 3/8", which is exactly the distance between the two "F" marks on the stator. So, with a Pamco, I always adjust timing so that one mark is on one of the F marks and the other is on the other mark. With a Pamco (or I assume XScharge), one cylinder will always be slightly advanced compared to the other.
 
Jim said:
I don't rightly see how that's possible with a dual output coil. :umm:
You have one coil firing both plugs from one trigger signal every 360°
Click to expand...
DogBunny said:
The Pamco has two triggers. I'm pretty sure the XScharge ignition also has two triggers.
Click to expand...
The pamco style ignitions use 1 sensor and 2 magnets because the cam rotates at half speed. Any small difference in magnet placement or strength will cause one magnet to trigger before the other. Can't happen on a crank mounted sensor because the is only one magnet.

I know this is clear as mud.:)
 
On the other hand the Boyer uses 2 magnets and 2 pickups. I think the trigger coils are wired in series to double the peak to peak voltage because the magnet on a cam orbits at half the speed and around 1/3 the radis .
 
DogBunny said:
Maybe I'm onto something totally different, but here goes:
The Pamco has two triggers. I'm pretty sure the XScharge ignition also has two triggers. The slightest error in the positioning of those two triggers on the plate in relationship to each other means that the timing of each side will be different. Even normal slop of the trigger assembly on the advance rod will result in trigger positioning inconsistencies.
Click to expand...
Yes... exactly. The one variable in a cam fired iggy is the trigger magnet. Every 360° the same coil and same trigger fire. But it's triggered by a different magnet every 360°
So, if there's a slight mismatch in the magnets, you'll see two distinct marks with the timing light. That will be seen on both sides btw.... since it's a single coil.

Edit: or in the case of a system that uses one magnet and two pickups, the two pickups will be the variable.
 
Thx Guys,getting a lil beyond my comprehension in terms of tech talk. GGGgary had a good point in stating that as long as either side does not
over advance past the advance mark at 3000 RPM .Then I should be good, regardless of what's happening at idle.
I will also check with arrow reversed as 5T mentioned. Thx for all the feedback. Wish there was a forum like this for the w800 Kawi I just purchased.
Off topic slightly, will running more advance boost power or just make engine run hotter?
 
Interesting read Gary, My Hanes manual states that advance can go thickness of advance mark past the line and still be exceptable
as per Yamaha. I personally feel better having it advance exactly on the line or a hair before. What I meant in other post was does retarding the
ignition timing under the correct settings change the engine power? Or change the characteristics of the engine and how it performs?
 

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