Timing Difference Between Plug Wires (the next problem)

Rlauchard

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Hi all,

Finished my TCI to points mod with quite possibly the help of every stinking member on this site. :)

Upon testing the timing, I have uncovered my next problem to which I don't know where to start. When I hook my timing light up to my left spark plug wire, my timing is in between my F mark. When I hook my timing light up to my right spark plug wire, my timing mark is just outside the right F mark mark (see my illustration picture attached).

Now...XSLeo had a great explanation on how both plugs are fired at the same time, thus both spark plug wires should measure timing the same.

So, here is what I've done to ensure that this is not user error...or rather KNOWN user error.

- Timed to the right side spark with timing light (NOTE, my timing light does not care on it's orientation to the plug wire)
- After getting the bike to start, I get it to where I can run without the choke
- I synched the carbs with manometer
- As signature says, I'm running uni-foam filters, 45 pilot, 137.5 mains about 2.5 turns keeps the bike running
- Exhaust is a 2-1 and shown in the other picture attached
- The spark plugs have black carbon after about 1/2 hour of running (total, not all at once), they were new as of last night

I would love some help determining where to start to find the issue.
- Stuck choke?
- Gummed up carb jets somewhere (cleaned them twice and they appear ok)?

Feeling overwhelmed...breathe, breathe... :yikes:
 

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I'm not understanding exactly what you've done to your ignition set-up here. Did you revert back to points or did you just install the bushings and advance rod in your cam so you could switch from a TCI to a PAMCO? Also, you should be setting the timing to the left cylinder indicator. The right one is indicating it's slightly retarded which isn't a big deal. However, where you set the idle timing also determines where the full advance timing will be. Set the idle timing too advanced and full advance will be too much as well. You don't want that and that's effectively what you've done.
 
Check the timing to see that it's advancing to the correct position at 3k rpms and not over advancing. That's more important than the idle timing. Stop calling Pamco "points", big difference.
 
Sorry...clarification:

Removed TCI. Installed the PAMCO kit from Mikes. Dual output coil, bushings, advance rod, plate, pamco plate.

I set the timing to the left cylinder indicator. In the diagram, the is the red L line in the picture above. The instructions say that the timing mark just needs to be in-between the F mark.

So, as I was installing, XSLeo posted that the timing should be the same when using the timing light from either side. You are saying that's not the case and that it's ok?

Can you explain what you meant by 'you don't want that and that's effectively what I've done'? Are you saying that where the idle timing is is too far to the left and therefore full advance will be too much, or is there something that the bike is doing that I posted that is a 'symptom'?
 
Check the timing to see that it's advancing to the correct position at 3k rpms and not over advancing. That's more important than the idle timing. Stop calling Pamco "points", big difference.

:doh: Shit. Sorry! I have no idea what points are to know the difference. pamco, pamco, pamco.
 
You need to check your full advance timing and adjust the pamco accordingly to reach the mark and not over advance the timing.
 
So if you're running a Pamco, this is wasted spark and they should both fire at the same time, so it doesn't matter which one is which. Just out of curiosity, have you tried swapping wires, plugs, and coils around. Have you checked your plug gaps? Something is making the difference and by process of elimination you should be able to figure out which part it is.

Also, the others are quite right: where your full advance winds up is more important than idle. You want to double check what it does at 3k.
 
Your advance unit advances the timing a set amount, something like 25°. Therefore, if you set the idle timing too advanced, your full advance will be too much as well. You don't want to run with more full advance that specified or you can hole a piston. Your pic indicates the left cylinder idle timing in spec but the right cylinder slightly retarded. So then you say you set it to put the right cylinder in spec. That's going to push the left cylinder idle timing outside the spec and to the left (more advanced) side of the marks. That, in turn, will push the left cylinder's full advance timing too far advanced.

I don't know why you're getting two different reading. They should be the same with a PAMCO. Maybe you have excess play in the advance rod? Since the bushings are new, there shouldn't be excess side-to-side play but you may have excess in-out play. That's been reported on some of the Mikes PAMCO kits. Does your timing image jump around a little as you view it? Too much play in the rod can cause that as well.
 
Just got back in and read the posts.....

So, let me address these questions:

5twins: I didn't set the timing to the right side, I just checked it...and thus, the questions started. Have trouble being clear.

Grinder: You are correct, man oh man. I set the timing according to full advance. The idle sits close to the left mark, but what a dramatic difference.

5twins: It does jump around a little, but not enough where it skews the results of the idle mark...the full advance wiggles, not so much jumps, but holds fairly steady.

Marvelicious: I didn't switch the plugs, wires or coils. The coil is new, the wires measured good resistance, but I like the thought of measuring the gaps. I didn't measure them. I'm using the Autolite #63...not sure if the gaps come preset...I'm assuming I should check them before they go in (probably a site-wide headslap on that comment).
 
Indeed. You should always check and set your plug gaps on a bike. Many plugs do come pre-gapped but that's usually for car use and cars run bigger gaps. If your plug gaps are too big, that could very well be contributing to your problems here. Stock gap was about .028" but with the PAMCO and high output coil, you can go a bit bigger. I wouldn't go over about .035" though. I run mine @ about .032".
 
Good morning!

So, since I made the 'oh, I should measure this' statement about the spark plug gaps, you can be sure that I've never done it.

Here was my process:

1. Look at manual for 81 SH model to get plug gap (.027-.031)
2. Using the Dual output performance Ignition Coil, I decided to set the gap at .032 for both plugs
3. Took the .024 feeler gauge and the .008 feeler gauge and put them together
4. Bent the gap down a hair to where the .032 combo-gauge goes into the gap, but has a bit of drag

If that's right, then, today I'll go out and put them in to see if that helped with the timing difference. If not, I'll switch the caps/wires to see what that does.
 
Rlauchard,

None of the above has anything to do with having an observed difference in the timing between the two cylinders. The current for both cylinders comes from the same coil at exactly the same time. If you are observing a difference, then that is all it is. An observation, not necessarily a reality. As I tried to explain to you in your earlier thread, if you are observing a difference in the timing, then there is probably something wrong with your method of observation. Specifically, it could be caused by the different polarities of the two spark plug wires. You have subsequently said that you are getting a strobe from either plug wire with either orientation of the timing light clamp, but that doesn't mean that all four of those combinations are going to be displayed in exactly the same time. Specifically, if your timing light is working with the positive wire it is being triggered on the downslope of the pulse instead of the upslope and there is a time difference between the two. That is what you are probably observing. So, in the interest of science and truth, there is a way for you to absolutely determine which wire is the negative and which is the positive and then connect your timing light clamp appropriately. Here it is, but it is not for the faint of heart:

spark_polarity.gif


1. Remove the spark plug cap from one of the wires.
2. Hold the spark plug wire very close to the spark plug terminal with a standard #10 pencil between the end of the wire and the spark plug terminal.
3. Observe the pattern in this picture to determine the polarity of that wire. The picture shows what the negative wire should display.

4. You only have to do this test on one of the wires because the other wire will be of the opposite polarity.
5. When you have determined which wire is the negative wire, connect your timing light clamp to that wire with the arrow pointing towards the spark plug.
6. Clamp the clamp on the other wire in the opposite direction.

Now, you will probably need about 5 hands to do this test, so find someone brave enough to help you. Also, you can make it easier by removing the slotted disk from the advancer and spin the rotor by hand without having to turn the engine over.

I will be doing a demo of this procedure in my next Seminar and Clinic to be held at an undisclosed location in Hawaii
 
The 0.032" gap will work fine for you. With a good strong coil, you can increase that to 0.035". I'm using an Accel coil with the plugs gap at 0.035", and it has given me 56 mpg, instant electric starts (1 kick using the kick starter), and good exceleration.
 
:yikes::yikes::yikes::yikes::yikes::yikes::yikes:

Once I got the full advance right, the engine is running great.

It sounds like my left side was timed fine and that I should call it quits OTHER than trying to now get my plugs right...meaning, jetting, mix, etc, etc.

That's what I'm reading. I've got the gaps set, the full advance set, etc.

I didn't even know how to read my plug gaps until this morning...there's no way I'm stuffing a pencil in between the plug and plug wire. I AM faint of heart.

Now, I would like to hear more about this Hawaii thing....:bike:
 
Count me in for the seminar:thumbsup: I suggest that when the seminar is held, an establisment, perhaps in Waikiki, that serves alcohol, is chosen. Copious amounts of alcohol will give the volunteers false courage, and dull their nerve sensing, when the shock occurs. :D
 
Count me in for the seminar:thumbsup: I suggest that when the seminar is held, an establisment, perhaps in Waikiki, that serves alcohol, is chosen. Copious amounts of alcohol will give the volunteers false courage, and dull their nerve sensing, when the shock occurs. :D

Yes, well, I will also be demonstrating the new PAMCO high Voltage wine bottle cork remover at the seminar. Basically, it just vaporizes the cork, because once a cork has been removed, what's the point of keeping it?

Wine allows you to transition through the "zone of truth". Your mind is all confused when you are sober. Prejudice, lack of confidence and ennui rule the sober mind. :doh:

As you consume wine, one glass after the other, you pass through the "zone of truth" where all mysteries are solved, all women are hot, and the skies are not cloudy all day. :)

You do your most imaginative work while in the zone of truth, but it is short lived, because the zone requires a continuous flow of wine to keep the lamps aglow, which soon dim as the flow of wine drowns the flame of truth and beauty and all becomes blurry and uncertain, just as it is when you are sober. :wtf:

So, be prepared...take notes and have lots of witnesses as you move rapidly through the zone, because it's truth is fleeting, and the fall is steep, and all those hot women will soon cool down, and the empties will rattle around the floor reminding you that the truth is a transient... :banghead:
 
Actually, a wine bottle cork can serve a very useful purpose on your 650 if it is a Standard and you've installed the tapered steering head bearings along with a grease nipple in the side of the neck to keep them lubed. The slot in the stem for the neck-mounted steering lock allows grease through. The bottom of the stem is open so that excess grease just falls out. You need to plug the bottom of the stem and a wine bottle cork is just perfect for this. I recommend using an Italian wine bottle cork. Being Italian, it will make you go faster, lol.
 
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