Topic: can't set static timing to F mark

[Joust]

i found this instruction
"The light is only used to indicate the exact moment the points open.  The light should have the alligator clip attached to the engine case or fins (ground) the pointed end (probe) should be touching the part of the point assembly that moves with the cam.  Points open, light comes on, F mark in the window.  Do this for 1-4 and 2-3,  start and enjoy."
its a common instruction repeated many times.
I am helping 76400F to get his , was my bike , running after his fantastic rebuild.
To make a long story short, we cannot get the timing to turn the light on at the F mark. No matter how we adjust the plate with the points on it, we can only have the light come on at a much advanced timing point. we can get it on the " marks but nowhere near the F mark.
The bike will not fire. We got a tiny bit of smoke a couple times but no real firing.
We also found that the advancer we seized up pretty good but i believe that will only affect the advance. its not stuck advanced. at least not that i can see. we even tried prying the advance dogs open and messing around with the points plate with the advance dogs in the out position. that just exacerbated the problem which is what i expected.
does anyone have any insight into what is wrong here?

another note here. We changed the points to an old original set. once cleaned up they seemed to work the same as the replacements. there are some spacing difference between the two but compensated for appropriately. without getting into too much detail there, they both behave the same.

[madmtnmotors]

You need to "make it right" first. Remove, clean, and lube the advancer so that it works properly. This will insure that the advancer is not part of the problem. When you reassemble the advancer, make sure the point cam is oriented properly. The points cam can be installed 180 degrees out.

[DaveBarbier]

Did you set the point gaps first?

another note here. We changed the points to an old original set. once cleaned up they seemed to work the same as the replacements.

Are you convinced this isn't the issue? Because I'm not. "Seemed to work the same as the replacements." doesn't inspire confidence.

How about you take some photos of the points assembly with light connected and post it.

[Joust]

You need to "make it right" first. Remove, clean, and lube the advancer so that it works properly. This will insure that the advancer is not part of the problem. When you reassemble the advancer, make sure the point cam is oriented properly. The points cam can be installed 180 degrees out.

we plan on fixing it but cannot figure out how to get those dogs off that plate? don't want to break them.
i cna see how it can be installed 180deg out but it was never apart so we assume it was installed correct. there is only one way to install that assembly so we cannot for the life of us figure out why we cannot set the spark point to the F mark.

[Joust]

Did you set the point gaps first?

another note here. We changed the points to an old original set. once cleaned up they seemed to work the same as the replacements.

Are you convinced this isn't the issue? Because I'm not. "Seemed to work the same as the replacements." doesn't inspire confidence.

How about you take some photos of the points assembly with light connected and post it.

we did set the gaps. they are uniform...i.e. no bent shaft.
after i noticed the difference in the points we changed 1-4 points to the old one. it worked the same.  what i meant from the difference was that the point contacts are a lot thicker on teh old ones compared to the new. 76400f pointed out that the rubber on the cam lobe is thicker to compensate for that on the newer points. SO it balances out. We proved this with testing which is why i commented that it seemed to work the same.

[DaveBarbier]

The points plate might have play in it. Even a hair of movement can screw things up. You can shim the plate like how I did in the below picture. It makes sure the plate is snug and won't move as you adjust and rotate the crank. You can trim off a bit of feeler gauge and keep it in there to ensure it doesn't move on you. There's info in the FAQ about this tip.

Do you know the manufacturer of the points plate and points? A lot of members, including me, have had issues with aftermarket plates, condensers and points. You might want to verify these are TEC or ND (Nippon Denso)

Daiichi is garbage, their logo is a three pointed flower.

[madmtnmotors]

we plan on fixing it but cannot figure out how to get those dogs off that plate? don't want to break them.

By "dogs" I'm guessing you are talking about the counterweights, The weights are held to the plate by a circlip on the pivot post. They are also captured by the points cam which simply lifts off unless corrosion has begun to fuse it to the center cam post.

there is only one way to install that assembly so we cannot for the life of us figure out why we cannot set the spark point to the F mark.

That is correct. I was merely stating that when you service the advancer assembly that you be sure to reassemble it with the points cam oriented properly. If the advancer assembly is "froze up" then it needs to be corrected.

[76400F]

Definitely Daiichi points, unfortunately.

Can shimming the plate really affect the timing?

[Joust]

The points plate might have play in it. Even a hair of movement can screw things up. You can shim the plate like how I did in the below picture. It makes sure the plate is snug and won't move as you adjust and rotate the crank. You can trim off a bit of feeler gauge and keep it in there to ensure it doesn't move on you. There's info in the FAQ about this tip.

Do you know the manufacturer of the points plate and points? A lot of members, including me, have had issues with aftermarket plates, condensers and points. You might want to verify these are TEC or ND (Nippon Denso)

Daiichi is garbage, their logo is a three pointed flower.

I'm not sure what you are refering to but my problem is not things moving. It has everythign to do with not being able to get to the F mark in the first place. nothing to do with holding it there.
The plate and one points are stock honda TEC parts. the other which we can swap is Daichi. but the plate is old original TEC.

Let me re-iterate the problem.
I can set the points statically to the || marks. i would have to turn the plate about 3/4 of an inch more past its end stop adjust point to make it over to the F mark.
Its as if the cam lobe were swiveled on the timing advancer. but that cannot be because the cam and the plate with the timing marks are the same piece of metal.

[madmtnmotors]

Its as if the cam lobe were swiveled on the timing advancer. but that cannot be because the cam and the plate with the timing marks are the same piece of metal.

No, they are not. The points cam is separate from the advancer plate. The weights move the points cam to "advance" the timing...

What are you using for the point gap? Try setting to the small end of the gap range.

[Joust]

Its as if the cam lobe were swiveled on the timing advancer. but that cannot be because the cam and the plate with the timing marks are the same piece of metal.

No, they are not. The points cam is separate from the advancer plate. The weights move the points cam to "advance" the timing...

What are you using for the point gap? Try setting to the small end of the gap range.

i think we are saying the same thing. Yes the weights move the plate. but what i said was the plate and the lobe are the same piece. we are talking purely static here. so no matter where the weights are or the crankshaft is i "should" be able to set a timing point on the F mark using the points plate adjuster.
We set gap to 0.014"

[Joust]

Arguing with my buddy about this...is there a picture anywhere of this advancer mechanism dissassembled

[flybox1]

, we cannot get the timing to turn the light on at the F mark. No matter how we adjust the plate with the points on it, we can only have the light come on at a much advanced timing point. we can get it on the " marks but nowhere near the F mark.

this confuses me. . .
Are you attempting to get the bike to idle on the II marks?
The bike idles on the 'F' mark, and full advance at +/- 2500rpm between the 'II' marks

[76400F]

Hi again Fly. No, we're attempting to set the static timing as per the manual (as it turns out, I also screwed that up yesterday)...the light is coming on way in advance of the F mark. More in the 'II' marks. We're running out of adjustment to get it to light on the F mark.

[Joust]

No, they are not. The points cam is separate from the advancer plate. The weights move the points cam to "advance" the timing...

i think we are saying the same thing. Yes the weights move the plate. but what i said was the plate and the lobe are the same piece. we are talking purely static here. so no matter where
[/quote]
No i was wrong. i see that from a picture of a similar unit. This is definitely not the CB400f advancer but i assume its built the same general way.

regardless, we are not convinced that this explains our static timing problem when the advancer is in its static position. seized as it may be. Its soaking in carb cleaner and will be freed up and working before we proceed.

[Joust]

Hi again Fly. No, we're attempting to set the static timing as per the manual (as it turns out, I also screwed that up yesterday)...the light is coming on way in advance of the F mark. More in the 'II' marks. We're running out of adjustment to get it to light on the F mark.

^^^^^^^ what he said ^^^^^^

[DaveBarbier]

Definitely Daiichi points, unfortunately.

Can shimming the plate really affect the timing?

Yes, very much so. Read the link below from TwoTired in the FAQ. It helped me get my timing on when I ran out of adjustment room.

The points plate might have play in it. Even a hair of movement can screw things up. You can shim the plate like how I did in the below picture. It makes sure the plate is snug and won't move as you adjust and rotate the crank. You can trim off a bit of feeler gauge and keep it in there to ensure it doesn't move on you. There's info in the FAQ about this tip.

Do you know the manufacturer of the points plate and points? A lot of members, including me, have had issues with aftermarket plates, condensers and points. You might want to verify these are TEC or ND (Nippon Denso)

Daiichi is garbage, their logo is a three pointed flower.

I'm not sure what you are refering to but my problem is not things moving. It has everythign to do with not being able to get to the F mark in the first place. nothing to do with holding it there.
The plate and one points are stock honda TEC parts. the other which we can swap is Daichi. but the plate is old original TEC.

Let me re-iterate the problem.
I can set the points statically to the || marks. i would have to turn the plate about 3/4 of an inch more past its end stop adjust point to make it over to the F mark.
Its as if the cam lobe were swiveled on the timing advancer. but that cannot be because the cam and the plate with the timing marks are the same piece of metal.

You're describing an issue of running out of adjusting room that many other's have come across. A good work around is shimming the plate. Your problem could very well be the plate moving.

Shimming the plate can make big changes in gap and timing. Since the points are screwed to the plate, as the cam rotates it can push the plate around even very small amounts. Shimming keeps the plate stationary.

Read through this post by a senior member TwoTired in the FAQ.

http://forums.sohc4.net/index.php/topic,5752.msg47539.html#msg47539

Sometimes it can't compensate for the imperfections is Daiichi's points. But you might find that it gets you closer. If you have a good set of TEC points, use them.

[flybox1]

can you snap a closeup picture of your points plate as-is and post it for us to look at?

[DaveBarbier]

Shim the plate and then start with gap again on both points and then timing. Not sure if that's obvious or not.

And yeah, post pictures like Fly and I asked.

[76400F]

I'll have to do it when I get home tonight. I wasn't offended by the blast you gave me btw, Fly. Totally deserving. I've taken painstaking care to get everything on the bike perfect to this stage and I guess I'm hacking the most important part (engine) a bit in order to hear it run...

Thanks for the link, Dave. We'll have a look.

[Deltarider]

Are you sure you've set the 0,014 breakerpointsgap when the cam was at it highest? Reason I ask is that I remember someone who had set the gap without having the cam at its highest and as a consequence never could get it right. Below the advancer assy of a CB500/550 but I'm sure yours is almost identical. You could check the little carve in the rim faces the hole (shown in white cirkels in the pic at 5 o'clock). If yours hasn't been apart and bike ran OK before, don't bother.
 
About Daiichi the reports are mixed. Some have no problems with them.

[madmtnmotors]

From dave500's post from here:

http://forums.sohc4.net/index.php?topic=124077.0#quickreply

the ignition (points cam) can be set up 180 out, the (valve train) camshaft can not. They have index marks, pretty hard to spot if you don't know they are there.

The weights move the points cam. The advancer plate is stationary since it is pinned to the crankshaft. The points cam must be removed and replaced with a magnet loaded "trigger" when installing an electronic Dyna ignition.

[76400F]

The bike ran when it was parked (30 yrs ago) and the advancer has not been apart, so there's no way this is the issue.

[flybox1]

Are you sure you've set the 0,014 breakerpointsgap when the cam was at it highest? Reason I ask is that I remember someone who had set the gap at the F mark and as a consequence never could get it right.

+1 ^^^

[76400F]

I'm not certain about anything anymore, except that I'm not as smart as I thought I was.