Timing -- Lost

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Coyote
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Timing -- Lost

Post by Coyote »

I have checked the timing marks on the propeller with a dial indicator. They are spot on the money. So I'm timing the left, appropriately gaped at .014 and using a static timing light. The light goes out a degree or 2 short of the mark. I have rotated the plate as far as possible as far as it will go clockwise. Gets close but I run out of room on the plate slots. I need to tweek it just slightly more but there's no rotation room left. I am certain these points are stock and the bike only had about 3500 miles on it.
The point gap is center of the tolerance at .014. Would a wider gap or a lesser gap improve the situation?
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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jabcb
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Re: Timing -- Lost

Post by jabcb »

Had the same problem on a GT250. I used a wider gap & the bike runs just fine.

If my memory is correct, a wider gap advances the spark & a narrower gap retards the spark.
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ConnerVT
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Re: Timing -- Lost

Post by ConnerVT »

jabcb wrote: If my memory is correct, a wider gap advances the spark & a narrower gap retards the spark.
Correct. With a wider gap, the points open sooner (as well as close later).

The gap setting is pretty generous. only need to be concerned going wider on the gap if planning to run wide open, high RPM runs. The street and Daytona are two different animals.
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tz375
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Re: Timing -- Lost

Post by tz375 »

ConnerVT wrote:
jabcb wrote: ..... The street and Daytona are two different animals.
For you and me perhaps, but I hear that Coyote Chris runs the street like a Daytona 200 racer :wink: :lol:
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Re: Timing -- Lost

Post by Coyote »

What would be the upper limit on the gap? I doubt just going to top tolerance (a gain of .002) will do very much
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Re: Timing -- Lost

Post by Coyote »

Well I increased the gap to a little over .018. Now the points never close.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Re: Timing -- Lost

Post by Coyote »

I give up for tonight. Something is really goofy here. Now when the light goes out, the propeller is not even in the window. Yet with my indicator stopping .132 BTDC it is spot on the 'L' mark. And yes the indicator is in the left bore. So I know nothing is loose as .132 BTDC is always spot on the 'L' mark. Not that it makes a terrible amount of difference, I am turning everything in a clockwise direction.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Re: Timing -- Lost

Post by jabcb »

The GT250 was out further than your GT550 & I didn't need to open it up much.
Perhaps you should try .015
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

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Re: Timing -- Lost

Post by pearljam724 »

Dial guage.
Image Image
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tz375
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Re: Timing -- Lost

Post by tz375 »

at .018" the points should not be open all the time - something doesn't sound right.

It should be possible to simply make the adjusting slots a touch wider/longer but that's unusual.

Is it possible that the points cam is not keyed correctly or is the wrong one for those points? Ie Denso vs Kokusan. It has to be something odd like that.

550 runs the points backwards right, so you are checking it in the correct crank direction?
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Re: Timing -- Lost

Post by Coyote »

The iggy is 100% Kokusan. The cam is brand new and the correct one. Both the propeller and cam are keyed on the pin. I know nothing is amiss as I stated earlier .132 BTDC and the 'L' is aligned every time.
PJ. Dial gauge and indicator are one in the same. I wish something here was magnetic so I could get my 10th indicator on the cam. There would be no question about where the absolute high spot is.

Image
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Re: Timing -- Lost

Post by Coyote »

Can someone verify that the timing plate is in the correct index? I can't find any pictures of the Kokusan setup. Only illustrations. On the illustrations I find, the single condenser is in the 9 o'clock position. However, the dual condensers are right where they are here (4:30 - 5:30). I haven't messed it yet this morning as I need to verify the plate position first.
Here the left points are at the 3 o'clock position. Seems like I remember them being at the top, but it's been a long time.

Image
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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tz375
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Re: Timing -- Lost

Post by tz375 »

I was searching for a picture on line and then remembered that I had a bunch of pictures here somewhere of one.

That looks exactly like the 72 that passed through my hands last year. I have a picture here and it seems to be identical. Interesting that on "mine" the points plate was rotated almost as far as yours. It appears to be hard against the screw in the lower left slot.

I would try to lengthen that slot another 3mm and see if that gives you enough room to set the timing.

Image

Hope that helps
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Re: Timing -- Lost

Post by Coyote »

I got the left in. Gap is in tolerance and I didn't completely use up the slots. Working on the right now. Thanks for the photo.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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Re: Timing -- Lost

Post by Coyote »

OK. I'm about ready to throw in the towel. I was setting the right points and got close. Needed to tweak a little more ----- then it happened. The light on that cylinder stays on 360. When the points open, the light remains on. It was working and now it doesn't. I didn't change anything so I don't have a clue as to what happened. Everything was going just fine and the light was acting normally -- going off when the points open. now suddenly it stays on even after the points are visibly open. I can close them and operate the point with my fingernail -- light stays on.
I don't have clue as to what happened. Now I am way beyond frustrated. I should note that the other 2 sets work normally -- light goes off when the points open. It's just this right set that is giving me fits. I looked everything over under heavy magnification and see nothing wrong. I didn't loosen any of the pigtails. Just the 2 screw that allow you to rotate the point set. It just about has to be shorted somewhere I would think. But where? why?
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
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