Points plate almost out of room

Hey guys, I was static timing my bike over the weekend and my upper points plate is almost all the way to the right. I mean it has less than 1mm that it will move to the right. Is there something wrong here? Is ther some way that I can fix this, like maybe my advance rod or can I turn the cam on the end of it?

your points are wearing out.. try setting them to either the min or max gap that your manual gives you, one setting will give you more room to move it

Ah okay. Thanks. I'll do that. I've never dealt with points before. All of my older vehicles that had them, I would replace with an HEI. Which I will be going with a Pamco soon on this.

Running out of timing plate adjustment can be a sign that your cam chain is stretched out and nearing the end of it's service life. Since the Pamco adjusts in the same manner, you may encounter the same problem with it.

I'm leaning towards the cam chain. I've suspected it might be worn out for the last few weeks. How much longer could I be looking at with this chain? Are there any other symptoms to watch out for? I'm hoping to make it another month or so before I have to tear into it. Or will that be a bad idea?

Well, if you can't adjust the timing to spec any more, the chain is probably about done in. You can gain some more time (rest of the season) by filing the slots in the advance plate so you gain more adjustment but that's not solving the true problem. It's not uncommon for the chains on these to be shot by about 20K. Granted, they can and do last longer if properly maintained but there's the rub - they never were.

Well that explains why I'm almost out of canchain adjustment at 16k mile. PO didn't maintain the bike properly.

Right. As the cam chain stretches, the tensioner pulls the camshaft CCW, retarding valve and ignition timing. Wear on the cam followers of the points is compensated for by setting the points gap, and if the gap is set at the maximum .016" and you still can't advance the spark far enough, the cam chain is usually to blame.

Don't forget to inspect the ATU. Be sure that worn bobweights haven't stretch the advance curve.

"Don't forget to inspect the ATU. Be sure that worn bobweights haven't stretch the advance curve."

How do you check that? I don't understand what you mean by stretch the advance curve. Sorry if this is a dumb question, but I have never dealt with points before. This type of ignition is new to me.

I'm going to see if I can find something about it on here right now.

Okay, so do you mean that I should check that I am full advanced at 3000 rmp? And if not, it could be worn bob weights or springs? That is what I understood from you and pete's discussion about it.

Return ATU (advancer) to correct range

Since I've had the bike, I realized the timing range of the ATU was too large. When set at the F for idle, the timing would go well past the fully advanced mark. This was not safe for engine longevity, so I would compromise by moving the idle timing towards the TDC mark. Not the best solution!

grizld1 had mentioned a few years back that you can adjust the advancer weights to bring it back into range by peening. I thought I need to try that, but never got around to doing it. Well, finally this spring I took the weights out and peened the little tangs on the weights. grizld1 was right as usual.

I found my tangs at 0.156". At first I only peened mine to about 0.161", but the timing range was still too expanded. OK, so I removed the weights again, and I decided that the answer is to keep peening the weights until there was a very tight fit in the slot in the "slotted disk". Yamaha made the slot in the slotted disk a specific size for a reason................it gives the correct timing range of 25 degrees (15 to 40 degrees).

So, I just peened some more and did trial fits until the tang fit in the slot was a very close fit but not too tight that it would bind. It ended up at 0.168". That's a 0.012" increase in width of the tang. Your bike may be different. Just peen and trial fit until you get that "tight" fit in the slot. My timing light now revealed I had correct timing at both idle and at 4000 rpm!!

Thanks grizld1 for a great tip...................a very simple fix.

Thanks RG. I am going to go through everything tomorrow and see if I can make things right er. When you peen the tangs, do you hit the face or the edge?

You pound on the face to widen the tang so it fits tighter in the slots of the little disc. As the tangs wear, they get looser in the disc slots. This allows the weights to turn the advance rod more and that "stretches" the advance curve. Instead of advancing just 25° as it should, the ignition advances more. That's why you always need to check your timing at both retarded and advanced marks on these bikes. That shows you if you're still getting just the right amount of advance.

Edit - The more thought I give this, I don't think the worn tangs advance the rod more, they allow it to retard more when it comes back to rest at idle. The end result is the same though - you have an advance mechanism that is now moving through more than the proper 25° of range while operating.

5twins;

Yeah, I hear what you're saying..................I just see the wear as causing the 25 degrees to expand to a larger amount.

Its a good thing that its the fly-weights that wear (being softer than the slotted disk). If it was the slots in the slotted disk wearing, then peening the fly-weights would do no good at all.

I just did a 5 day trip, and when I came back I checked the timing, and it was still spot on. The wear must be very gradual, so once set, its good for a lot of kms, or those extra long things they call miles.

If youve got the advance mecanism 180 out will give you the problem of running out of advance check the marks are allined in advance unit if 180 out then fix that & then swap the the points wires at coils around

180* off at camshaft=360* off at crankshaft=motor trying to fire 15* BTC going into the exhaust stroke. The quick fix is to switch plug wires, after which the left cylinder points will be the upper pair on the main plate. All that has nothing at all to do with range of adjustment.

Okay, so today I am installing a Pamco. I checked the weights on the advance side and they are worn flat out. Literally flat on one side. I am going to try and peen them to get them tigher, but I don't expect that I will get them anywhere near what I need them to be. I will have to order new ones next week I guess. I am glad you guys told me about this, otherwise I probably would never have noticed there was something wrong.

jchrisk1;

Can you post a picture of your bob weights?

I've already peened them. I got them tighter but they are not flat anymore.
The Pamco made a huge difference with all around performance. I did notice that my timing marks are jumpy. Is this because of the weights?

jchrisk1;

I don't understand what you mean "not flat anymore". Do they look like the ones in my picture? With the peening done, is the timing now correct at idle and at full advance?

I sometimes see 2 white marks in the "F" area, nothing to be concerned about. The important thing is that the timing does not go beyond the full advance mark at 3000 to 4000 rpm.

They don't look as good as your picture. I managed to get a little hump on the tops of them where they fit in the slot. Where they were flat is on the tops of the tabs that fits in the slot.
The timing mark doesn't go beyond full advance, it looks like it is just behind the mark.
I am goimg to order a new advance unit this week, just for my own piece of mind. The bike has been very reliable for me so far, I'd hate for something as easy as this to cause me problems.
Again, thanks for your help.
Chris.