Topic: pamco timing adjustment

[cheftuskey121]

I have a pamco with ultimate coils on my 750. I am trying to set the timing so I know its spot on. I am not sure of the procedure with pamco. to clarify I am not sure of the procedure with points either, this is the first time doing this. I have a timing strobe gun. I just don't know exactly what I am looking for, trying to do, how to do it....hope someone can take a few minutes to explain and help me out

my friend said to hook up the timing light to the battery and the #1 spark plug wire, and while the bike is idling shine the strobe light on the pamco and see if the TF for 1-4 is lighting up as it spins around. is this correct? then how do I set it for the advance? am I supposed to know my bikes advance rpm. I have a 750K1

there is not much to adjust with the pamco plate. I think I can only rotate the whole plate clockwise or counterclockwise. its been running seemingly fine for 250 miles but because this is my first bike I have no basis of comparison. thanks

[dave500]

get the bike running at least and shine the strobe onto the marks,looking at the full advance twin scribed lines,rev the engine gradually higher and higher,dont be afraid,it wont hurt anything,youll see those marks start to move into line with the case index mark,theyll stop moving at some point like say 3500 rpm,,then once they stop adjust the plate to get them into line with the case mark,where the timing flashes when its idling so be it,if you have good fuel set the marks at the right most mark,if you have crappier ethanol fuel somewhere between the two.

[cheftuskey121]

thanks dave!

[dave500]

hold the rpm as you move the plate,even a little higher maybe,lock it down,your done,check it again and check the 2/3 side aswell by clipping the pickup onto 2 or 3 lead,it should read the same,,then check where it fires once idling,itll be spot on or perhaps slightly advanced,dont worry about it,these engines always run over 4 grand most the time anyway,the full advance is the important setting,an advance unit can also be considered as a "retard unit"itll be hard to start at full advance so its retarded for starting.

[cheftuskey121]

ok, checked it out tonight. when i get the advance on the first of two tick marks for advance, the idle is in between the 1 and 4, past the tick mark for idle. this cant be right. I have to advance the plate so much just to get the advance to line up that the idle is off, or vise versa.

[dave500]

ignore where it ends up at idle,,so be it i think i said,i shouldve been more clear,set the full advance correctly,,then ignore where it ends up at idle,unless you want to start frigging around with springs and weights,,be sure the advancer unit isnt sticky and has a smooth action to it,itll spring back and forth if you twist it.

[brandEn]

ignore where it ends up at idle,,so be it i think i said,i shouldve been more clear,set the full advance coerrectly,,then ignore where it ends up at idle,unless you want to start frigging around with springs and weights,,be sure the advancer unit isnt sticky and has a smooth action to it,itll spring back and forth if you twist it.

+1

[cheftuskey121]

Ok cool. I read it right, just leery about it. The advancer moves freely and snaps back no stickiness. I ground off the little pin on my advancer (early year bikes had em). Will set that again later tonight after work. Happy Father's Day all!

[pamcopete]

Life would be so simple if we could just ignore our problems and focus on the good stuff, but, alas, that is not the way things work, including setting the timing on a SOHC Honda 4.

Whether the springs are too tight or too loose, setting the timing to full advance will cause the timing at idle and between idle and 2,500 RPM to be too far advanced.

As long as your advancer is not worn out, you cannot exceed full advance if you adjust the timing at idle.  With weak springs, you will not get to full advance because some of the movement of the weights would be used up at idle. With tight springs, full advance will occur after 2,500 RPM. In both cases, if you set the timing to full advance instead of at idle, the timing at idle will be advanced. In the case of tight springs, if you set the timing to full advance at 2,500 RPM, the timing will then exceed full advance at engine speeds higher than 2,500 RPM. Not Good.

Another way to think of it is that the device that we call an advancer is really a retarder whose purpose is to retard the spark at engine speeds below 2,500 RPM for easier starting and protection from the damaging effects of too much advance.

So, as with so many pesky details in life, you have to in this case end up with the timing in the correct spot for both idle and full advance. It's OK to set the timing at full advance first, if that is what you prefer, but you still have to check it at idle and adjust / replace the springs to achieve the correct timing at both ends else you risk hard starting, pinging and idle hover.

I know. It’s pesky, like filing your taxes, but it has to be done to avoid unnecessary pain.

[chewbacca5000]

Hi Pete,

Does the CB500 use the same pamco ignition as the CB750?

Thanks!

[andrewk]

You're not talking about the indexing pin on the back of the advance unit, are you?  You need that...

[Eddie]

A separate total timing adjustment would be awesome...but.  On the old mechanical advance dist. for SBC.. you could adjust the total amount of advance... so you could run idle advance at 12-13 btdc with an  total of "X" total advance... worked very well. of course if you went too far, hard starting.

[cheftuskey121]

Life would be so simple if we could just ignore our problems and focus on the good stuff, but, alas, that is not the way things work, including setting the timing on a SOHC Honda 4.

Whether the springs are too tight or too loose, setting the timing to full advance will cause the timing at idle and between idle and 2,500 RPM to be too far advanced.

As long as your advancer is not worn out, you cannot exceed full advance if you adjust the timing at idle.  With weak springs, you will not get to full advance because some of the movement of the weights would be used up at idle. With tight springs, full advance will occur after 2,500 RPM. In both cases, if you set the timing to full advance instead of at idle, the timing at idle will be advanced. In the case of tight springs, if you set the timing to full advance at 2,500 RPM, the timing will then exceed full advance at engine speeds higher than 2,500 RPM. Not Good.

Another way to think of it is that the device that we call an advancer is really a retarder whose purpose is to retard the spark at engine speeds below 2,500 RPM for easier starting and protection from the damaging effects of too much advance.

So, as with so many pesky details in life, you have to in this case end up with the timing in the correct spot for both idle and full advance. It's OK to set the timing at full advance first, if that is what you prefer, but you still have to check it at idle and adjust / replace the springs to achieve the correct timing at both ends else you risk hard starting, pinging and idle hover.

I know. It’s pesky, like filing your taxes, but it has to be done to avoid unnecessary pain.

good info Pete, thanks. after reading that though I am not sure if my springs are too tight or too loose. I would immediately suspect too loose since its old and hasnt run since 1980. I just don't want to go clipping the spring only to have it the wrong way. I will report back when I can fuss with it some more.

[pamcopete]

Hi Pete,

Does the CB500 use the same pamco ignition as the CB750?

Thanks!

Yes.

Pete