Topic: Timing Question

[IndyFour]

A couple questions regarding my first attempt at timing my bike...

Today I purchased an el-cheapo timing light from Harbor Freight and gave it a try on my 74 CB550.  Cylinders 1-4 were pretty close to the mark, adjusted it and got it a bit closer.  2-3 were a bit off.  I pretty much maxed-out the clockwise adjustment on 2-3 to get it to the mark and it is pretty much on the F mark now.  Is this normal to have it turned so far?

One other question....as the engine ran with the point cover off, I could literally see a spark on the 1-4 points alot of the time.  My gut tells me that if there is a spark, the points will burn.  The points appeared to be pretty new and the surfaces seemed to be o.k. with just a bit of grey on about 50 percent of the contact surfaces.  What should this spark indicate to me, if anything?

Thanks for your help.

[OldSchool_IsCool]

Swap the condensers.  If the sparking follows, then the condenser is knackered. 

You are correct that heavy arcing will erode your points faces.  Do a search for "Hondaman Ignition Module" for info on a solid state relay circuit he sells that practically eliminated points erosion.

[mystic_1]

Did you set the point gaps before setting the timing?

If you gaps are off your timing will be all wrong.

Set gap first, then timing.  Do cam chain tension before both.

mystic_1

[mystic_1]

If you did gap your points before you started the timing then it could be that the points for 2-3 have a worn rub bar.  If this wears down to much it keeps you from getting the 2-3 point timed correctly.

+1 also make sure point contact surfaces are not grungy or worn past limits.

mystic_1

[IndyFour]

No, I didn't gap the points prior to timing.  I forgot to get a feeler gauge while I was out today. 

I will do as you suggested and start over with the cam chain first.  I'm reading up on it tonight in my Clymer manual.  It seems pretty straight forward and easy....but when the manual talks about cylinder 1 being at Top Dead Center (TDC), how will I know I'm at that point?  Will I know by what the valves are doing under the tappet hole covers?

Thanks so much for the help.  I'm learning as I go. 

[Bill/BentON Racing]

Set your timing ,pt gap first>012-.016,then set 1&4 first,move complete plate,then set 2@3 move smaller plate,if not in adj.you can move smaller plate for 1&4 also,but do whatever to 1&4 first,then 2&3.you can also change your timing with  pt gap,wider gap advances your timing,narrorw gap retards it.Also when moving big plate,move it in the direction of rotation to retard,opposite to advance.Good Luck, Bill

[OldSchool_IsCool]

when the manual talks about cylinder 1 being at Top Dead Center (TDC), how will I know I'm at that point?  Will I know by what the valves are doing under the tappet hole covers?

There is a hole in the points plate that expose the timing marks.  There is a pointer on the case.  As you rotate the engine (clockwise) look for the T F 1.4 markings on the advancer plate.  When the T is aligned with the pointer, cyl 1 & 4 are at TDC. 

If the manual specifies "#1 at TDC of power stroke" then you can pop off the #1 intake tappet cover, place a finger on the tappet, slowly rotate the engine again.  You will feel the tappet fall then rise again.  This tells you that #1 is in it's intake stroke.  The very next time TF 1.4 aligns with the pointer, you will be at "#1 TDC of power stroke".

[IndyFour]

O.K.  this morning's update...

Went and got a good set of feeler gauges. 

First, I attempted to adjust the cam chain tensioner per the Clymer manual.  Got cylinder #1 to TDC and loosened the nut, screw did not move, nor would it move much at all manually.  There was maybe an 1/8 of a turn play in it...that's it.  The chain does seem a bit noisy to me when idling low (I'm assuming that's what the noise is anyway) and it always has been since I've had the bike.  Does this mean that the tensioner is toast?  I read in the FAQ about adjusting it while the engine is running....would I have any luck doing it that way?

I went ahead and adjusted the point gap which was a bit narrow.  The main plate didn't really move much to adjust after that.  The 2.3 plate is still maxed out all the way to the right and really could go further to get F right on the mark.

I'm guessing this timing issue is now all chain tension related?  If it's possible to adjust the tension while running, how would I go about doing it?

The bike really doesn't run too badly...just a bit noisy at low idle, but it runs pretty decent otherwise.  Every Honda of this vintage that I've seen sounds kind of the same, so I don't know if this is just normal engine noise or if it is the cam chain.  Maybe it's a common issue for alot of people and most of them sound this way because of noisy chains?

Thanks again for the help.

[MCRider]

O.K.  this morning's update...

Went and got a good set of feeler gauges.  

First, I attempted to adjust the cam chain tensioner per the Clymer manual.  Got cylinder #1 to TDC and loosened the nut, screw did not move, nor would it move much at all manually.  There was maybe an 1/8 of a turn play in it...that's it.  The chain does seem a bit noisy to me when idling low (I'm assuming that's what the noise is anyway) and it always has been since I've had the bike.  Does this mean that the tensioner is toast?  I read in the FAQ about adjusting it while the engine is running....would I have any luck doing it that way?

I went ahead and adjusted the point gap which was a bit narrow.  The main plate didn't really move much to adjust after that.  The 2.3 plate is still maxed out all the way to the right and really could go further to get F right on the mark.

I'm guessing this timing issue is now all chain tension related?  If it's possible to adjust the tension while running, how would I go about doing it?

The bike really doesn't run too badly...just a bit noisy at low idle, but it runs pretty decent otherwise.  Every Honda of this vintage that I've seen sounds kind of the same, so I don't know if this is just normal engine noise or if it is the cam chain.  Maybe it's a common issue for alot of people and most of them sound this way because of noisy chains?

Thanks again for the help.

The cam chain tension is only indirectly related to ignition timing in that we just want things to run smooth. many twins drive the points off the cam, so it makes a diff there. Our 4s drive points off the crank, so not so much difference.

Assuming you've set and experimented with point gaps within the allowed range, if you have the 1-4 points timed in good, and the 2-3 are maxed out then one may suspect the heel of the 2-3 points has been rubbed down. Are they new points?

I can't picture in my head if a taller heel on the 2-3 points would fix your problem or not. I might be backwards, in which case...never mind. So its just something to look into.

[IndyFour]

Yeah, the points appear to be pretty new as do the condensers.  I understand what you mean about the points being driven off the crank so that makes sense now that I think about it. 

Let me ask this....if I go with one of these electronic ignition replacements (total replacement for the points), are they more easily adjusted than these old points systems....or maybe they are more exact and don't need as much adjustment?  I'm not opposed to just replacing the whole shebang if that solves the problem.

[MCRider]

Yeah, the points appear to be pretty new as do the condensers.  I understand what you mean about the points being driven off the crank so that makes sense now that I think about it.  

Let me ask this....if I go with one of these electronic ignition replacements (total replacement for the points), are they more easily adjusted than these old points systems....or maybe they are more exact and don't need as much adjustment?  I'm not opposed to just replacing the whole shebang if that solves the problem.

Lots of opinions here, on aftermarket ignitions. I used a Presto-Lite electronic ignition with Andrews coils from 1980 to 1995 when i parked it. Set it once, checked it once (no change) in 50K miles. Replaced the spark advance once, not a Prestolite part, it was OEM.

I don't think Presto-lite is still around. Current popular similar item is the Dyna with various offerings.

HondaMan has an alternative to stock as well. Search for it, much written on this site.

I don't know enough about technicalities to judge the differences, other than to say i would not use the stock set up. My experience with the PrestoLite is hard to beat. My plan with my current rebuild is to re-use the prestoLite, coils, and replace the wires for color reasons.

[Spanner 1]

It's important to make sure your point gap is 14 thou. at the points widest opening as you turn the cam ( crank, always clockwise ). The point gap is not 'arbutory ' ! as the points need to stay closed for a specific 'time' ( dwell ) to build high-tension in the coil . Thus, 14 thou. point gap....... with good points it should be no problem to set the spark timing at the F mark for both 1+4 and 2+3. If out-of-wack, then point gap is not correct, IMO.
Also, once set, point ignition works very well...no need to buy electronic ign. just 'cos a little difficulty understanding your points/ timing.....plenty of help here !

[Bill/BentON Racing]

.014 is where we set them,I agree best setting,Should be able to adjust timing with them @.014,if not try a new set of pts.Bill