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Discussion Starter · #1 · (Edited)
Looking for a little help. Fitted a Pamco ignition with E-advancer and trying to get the timing right.

Bike is CB450 K0 1964 4-Speed

I rebuilt the carbs and ran them on the old ignition so everything was running fine and synced before I started. Wiring is all correct, coils where changed and spark is good.

I timed the ignition with strobe light based on the instructions and have the LF and F marks dead on the timing mark. Also when I bring the bike to 3000rpm (full advance) the timing mark is right in the middle of the advance marks which tells me my idle is below 1300rpm.

Everything appears to be 100% but the bike is backfiring a lot. Also a lot of carbon on the plugs when I pulled them.

I'm confused as when I first put in the electronic ignition before I timed it it ran pretty good and I had to retard it to get the timing marks correct. The symptoms also sound like retarding ignition so I'm wondering if my timing marks are wrong.

The timing mark I have is like the first photo there is no mark in the middle of the coil.

The timing mark I'm using is the one shown in the first photo at 10o'clock adjacent the cover bolt hole.
In the photo the LT mark is lined up with it (I know this is TDC and not the firing mark).


Before I timed it the F and LF marks where around 11O'clock in the middle of one of the coils like the below photo.
Image28.jpg
 

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Dont know if this will help but the sensors on the Pamco timing plate can be adjusted individually if so desired.
If you have followed all instructions to a T and you are 100% on the wiring and components you may have a problem elsewhere on the bike.
 

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Before I timed it the F and LF marks where around 11O'clock in the middle of one of the coils like the below photo.
so are you saying that you timed the ignition to a spot where you didn't have timing marks, as in the picture above of the stator with the notch on one of the coils, before you installed the Pamco? I don't see a notch in your stator. I'm not entirely sure of the differences between the 4 speed stator and the 5 speed (which looks like the one in your picture). they do have different middle numbers in the part number (283 vs 292) but many 450 parts that cross over to both models have the old middle, 283, as well as the newer 292 in many cases, so the stators might interchange but I can't verify. in any case, there would be a distinct difference in your timing from the place on the stator coil where the picture shows the notch, to the location of pointer on your stator
 

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Discussion Starter · #4 ·
Photos above were for reference attached photo below is my actual stator/rotor.

@hondapete Yes thanks I've done this so that my timing is the same on left and right cylinders.

@ancientdad see attached photo. When i installed the Pamco ignition initially I started the bike and it ran pretty good. When I checked where the timing marks where they were within the circle of the attached photo. I then followed the instructions to time the bike correctly and adjusted the LF (first arrow) and F marks to the mark in the square. I then checked at full advance and the second arrow (between unmarked lines) lined up with the mark in the square. Everything seemed 100% as per the instructions and I'm sure I've done it right but it's not running well its backfiring a lot.


IMG_20190127_183711.jpg
 

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That "pointer" at the top front cover hole is the correct index...
(assuming the rotor is correctly keyed to the crankshaft...Failure to use the woodruff key allows the rotor to be set randomly...Which I doubt in your case)

IF your red arrows are indicating the advance sweep, be advised that the correct spot is between the paired lines (about 3/16" apart ) one of which is indicated by the 6:30-ish positioned arrow in your pic......

That would indicate a problem with the advance unit (stuck...bad springs...both maybe?)
 

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Discussion Starter · #6 ·
@66Sprint Just to be 100% clear the correct pointer is the one in the red square yes?

My first red arrow is the LF mark which is aligned with the "pointer" (red square) during idle.

The second red arrow is in the middle of two unmarked parallel lines which is aligned to the "pointer" (red square) at >3000rpm (full advance).

I have no mechanical advancer Pamco uses electronic advance.
 

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The Pamco electronic advance doesn't actually advance the spark, it retards the spark at low speeds. You need to set the initial timing so the pickup sensor lines up when the engine is at full advance, the circuitry takes care of the idle setting. All the electronic ignitions work the same, Boyer Tri-Spark Pazon, they are all timed to full advance when setup.
 

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@66Sprint Just to be 100% clear the correct pointer is the one in the red square yes?

My first red arrow is the LF mark which is aligned with the "pointer" (red square) during idle.

The second red arrow is in the middle of two unmarked parallel lines which is aligned to the "pointer" (red square) at >3000rpm (full advance).

I have no mechanical advancer Pamco uses electronic advance.
Assuming the rotor and valves are timed correctly, then this would indicate correct timing of the spark. After-fire in this case would indicate a mixture problem, either so rich that unburnt fuel collects in the exhaust until it ignites, or so lean the same thing happens, both from incomplete ignition.

As noted above, you may want to pull the rotor to verify the woodruff key is still in there, and then check the exhaust valve timing.
 

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No need to pull the rotor, pull the left plug out and stick a straw or a pencil down in the hole with the rotor at the LT mark.. Roll it back and forth a little to see if straw is highest at the LT mark.
 
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The guys at the local shop that swears by this unit has informed me they time at full advance. Makes sense with what Mike stated (doesn't advance.. just retards at slower speed)....
As for making sure BOTH are firing at the proper piston location.. I read Pete would "split" the difference.. and I have also read where others have "locked down" one cylinder then adjusted/moved the other pickup /sensor (not the plate).
Kinda strange, I had prompted the question in the common motor / shockwave thread.. can something be installed in the ignition cuircut that would retard the timing at lower RPMs?? (Asking as if the shockwave installed at full advance with NO mechanical device)
 

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The guys at the local shop that swears by this unit has informed me they time at full advance. Makes sense with what Mike stated (doesn't advance.. just retards at slower speed)....
As for making sure BOTH are firing at the proper piston location.. I read Pete would "split" the difference.. and I have also read where others have "locked down" one cylinder then adjusted/moved the other pickup /sensor (not the plate).
Kinda strange, I had prompted the question in the common motor / shockwave thread.. can something be installed in the ignition cuircut that would retard the timing at lower RPMs?? (Asking as if the shockwave installed at full advance with NO mechanical device)
Everything you just said is correct.

Sent from my Pixel 3 XL using Tapatalk
 

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Discussion Starter · #12 · (Edited)
Ok so just to clear up a few things I have both pistons firing at the proper piston locations adjusted exactly according to the instructions. I have checked timing both at idle and full advance and everything is spot on.

Everything I have read states the Pamco E-Advancer advances the spark between 1300rpm in 3000rpm. That the LF/F marks should align at no advance and the parallel lines should align at full advance. I don't understand the replies that the ignition doesn't advance it only retards.

I've checked the piston position on the left cylinder in relation to the LT mark as Mike describes and it is bang which makes sense and tells me that I'm working off the correct marks.

This means I have another problem. Is it possible my spark is at the incorrect cycle i.e. intake instead of compression would that explain my problem. Or is it just pure fuel related.

I did rebuilt the carbs and set the float heights (20mm) before all this. Idle screws were seated and backed off 1.5 turns. Not sure if its relevant but I replaced the main jets with 130 instead of the 125 that was in it. Not for any particular reason except these came in the ultimate rebuilt kit from 4into1. If i can't get anywhere i will put the old jets and needles back in but I don't think this is the issue.
 

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Discussion Starter · #13 ·
Also just to be thorough I'm going to check all the cam marks and valve clearances. Do I need to order new gaskets when taking off the valve covers?
 

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Ok so just to clear up a few things I have both pistons firing at the proper piston locations adjusted exactly according to the instructions. I have checked timing both at idle and full advance and everything is spot on.

Everything I have read states the Pamco E-Advancer advances the spark between 1300rpm in 3000rpm. That the LF/F marks should align at no advance and the parallel lines should align at full advance. I don't understand the replies that the ignition doesn't advance it only retards.
This is a semantic argument; technically, it can only delay (retard) the spark from the reference signal, but since it begins at full delay (retard) until the rpm rise, it 'advances' the spark by reducing that delay until it reaches 0.

I've checked the piston position on the left cylinder in relation to the LT mark as Mike describes and it is bang which makes sense and tells me that I'm working off the correct marks.
Good - that means the rotor is installed correctly, which, if the Woodruff key is in there, is very hard not to get right.

This means I have another problem. Is it possible my spark is at the incorrect cycle i.e. intake instead of compression would that explain my problem. Or is it just pure fuel related.
It won't run at all if the spark timing is on the wrong cycle, which leads to the fuel.

I did rebuilt the carbs and set the float heights (20mm) before all this. Idle screws were seated and backed off 1.5 turns. Not sure if its relevant but I replaced the main jets with 130 instead of the 125 that was in it. Not for any particular reason except these came in the ultimate rebuilt kit from 4into1. If i can't get anywhere i will put the old jets and needles back in but I don't think this is the issue.
I'm surprised it ran well with the 125 jets, which would be rather lean for the later models, but may have been correct with the K0. Looking at my parts book for the K0, the main jet range is 120, 125, 130. Since you said the plugs were sooty, I'd put the 125 jets back in. Also, make sure there are no cracks in the rubber boots, and try spraying carb cleaner around the throttle seals, to see if the idle changes.
 

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Ok, you said BEFORE you put the EI "..it ran pretty good"...,you rebuilt the carbs AND you said now the timing is on..
now here is my question.. you had backfiring and sooty plugs..
is it still backfiring?
Do you still have sooty plugs?
I'm guessing you were looking at installing a Pamco to help FIX ur issues...
.. a back fire can be a lot of things, from running rich(unburned fuel) to a leaking exhaust manifold (air going back into the head). With the soot on rob plugs.. in betting your either running RICH, or you have oil entering the combustion chamber somewhere (valve guide or rings)..
If your timing is correct idle and full advance.. AND you have gone through the carbs (4 into 1 has quality stuff).. you may want to dig a bit deeper...,
Did you EVER have this running proper??? If ur timing is correct, you have either a fuel or "oil" issue...
 

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Discussion Starter · #16 ·
@Rob the Pamco wasn't fitted to cure any problem it was part of a general reliability upgrade.

Summary of how I got where I am.

- I rebuilt the carbs using 4into1 ultimate kit.
- Tested the bike on points ignition (as I got it) and it ran great went for a drive no problems
- Ripped out the points and put in Pamco. Installed the sensor plate by aligning the notch as described but DID NOT time the ignition.
- Tested the bike and it ran great at idle and down the road.
- Timed the ignition exactly as per the instructions and have confirmed the timing marks are correct.
- Now it splutters and has after burn.

Whats bothering me is that it ran fine before and also initially with the electronic ignition.

Is it possible that this bike just likes a little advance? Or is there something up

- I'm in Ireland running 95 octance (RON) unleaded fuel which burns slower...... am I clutching at straws here?
- Could a loose cam chain give similar symptoms?

I also just realised I have a photo of the old points location so I might put these back in and check the static timing and see where that leaves the LF mark. Maybe it was advanced a little before....
 

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It may be as simple as "bad gas".... a way to easily eliminate the Pamco is to basically eliminate the Pamco.. if it fixed ur problem, your EI may have crapped out..
R u by chance running the origional Rectifier/Regulator??? EIs don't take well to voltage spikes.. but I have only heard of them completely craping out..
 

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Discussion Starter · #18 ·
I emptied the gas tank before running it, cleaned out the petcock and put on new fuel lines. The fuel that went into the tank was from a jerry can I use for my garden machines (its not mix before anyone asks) and its reasonably fresh with 1-2months. Same fuel when it was running on points.

Electrical system is completely rewired. New rectifier/regulator combo from 4into1. This is the kit I bought https://4into1.com/electronic-ignition-kit-with-regulator-rectifier-pamco-honda-cb-cl450k-cb500t/

Apologies if I come across as defensive I'm like that by nature but just trying to rule stuff out.
 

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No.,it's all good.. just trying to eliminate possible (simple) things..
 

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Discussion Starter · #20 ·
Some more info. With the carbon fouled plugs and it seeming to run better advanced I'm inclined to think its rich mixture so I tried to start the bike cold with no choke to see what happens but it wouldn't start with or without the choke. I started to get popping through the left carb and I then got a burning smell (its a UNI foam filter) and discovered it was hot/melting.

Pulled both air filters and it still won't start. At a bit of a loss think I will double check static timing with the old points and then bring it to a pro.

If it makes a difference its cold out maybe 2 Celsius or 35 Fahrenheit
 
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