76 wing idle issues. Done for now!

[kerryb]

snip-
Now I'm going to concentrate on timing and ignition details.

kerryb
I was reviewing your Topics history, and noted you had puzzled why/how the Dyna S wires insulation sheath had been heat damaged 2 inches from its exit of the points cavity ( "Dyna s 12v supply wire melted", dated Jan.2022. )
Appears you have since then, removed that injured Dyna S assembly and reverted back to the breaker points and condenser system.

Are the factory installed, original GL1000 ignition coils still in place ?

We have a communication breakdown... this bike never had a dyna s on it. I have worked on other gl1000 wings that had a dyna s on them but not this bike. I tried to look up that post, but I don't know how to.

Making an inspection plate sounds like a good project, Consequences of failure are very low!

[gltriker]

Oooops it was a 1977 GL1000
https://www.ngwclub.com/forum/viewtopic.php?t=77056

--

[gltriker]

[quote=kerryb post_id=821850 time=1701871946

Snip
We have a communication breakdown... this bike never had a dyna s on it. I have worked on other gl1000 wings that had a dyna s on them but not this bike. I tried to look up that post, but I don't know how to.
[/quote]

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[kerryb]

Thank you gltriker, learned something new today!

[redglbx]

Kerry, one other thing I would suggest is to check the valve clearances for a while. On my 76 LTD I restored things and started running it after it had been sitting on a shelf in a warehouse for a while. After running it about 50-75mi it started running very badly and ultimately I found that the valve clearances had closed up to zero clearance on some. After resetting them to the .004in spec it ran fine.

I had to reset the clearances several more times over the 1st 1k or so. I think that over the time it sat I believe the valve faces & seats rusted and running it beat the rust off which closed the clearances up. worth checking.

[kerryb]

That's another detail I wasn't sure about...the manual spec is .004, but the recommended spec by the guru's here is .006, so I split the difference at .005 on all valves. I also did a compression and crude leakdown test. While I can't quote the numbers off the top of my head, they were all quite acceptable,with no leaks detected by ear.
I performed the intake leak test with propane, no leaks detected.
Idle is now down to under 1000rpm, but is a little lumpy (as expected), still somewhat slow to return to idle, and the flat spot is still there. I've decided to redrill the idle air jets to #98 size.
Still debating shortening the advancer springs, but they don't seem obviously loose! So I guess the next step is to look in the carbs again for more issues.

[redglbx]

Kerry , sounds like you’re getting there ! The idle is a bit lumpy on the 75-77’s as they have pretty “hot” cams oe ! OE idle is supposed to be 900 to 1100 rpm, I run mine at 1100 just because it tends to be charging better and circulating coolant better (my opinion) and minimizes any clutch rattle. When things are setup well you can turn the idle waaay down, mine will go down to under 400rpm on a good day, but I do set it to 1100 for normal operation.

But again you might want to recheck the valve clearances to see if they have closed up any. As far as clearance goes i don’t know which if any is better, my oe 76 has them set at .006in but my 76 LTD is set at .004in. If I can get healthy enough I plan to do some comparison testing on my standard 76 to see any differences. I plan to look at compression readings and idle vacuum readings to see how things affect each other. That’s the plan anyway.

But, I moved the bike into my shop back in April/May to do this testing but alas it’s sitting untouched !

The getting old stuff just sucks ! But it definitely beats the alternative ! So enjoy the time you get to tinker with theses things even when they’re frustrating.

[Sidecar Bob]

Slow return to idle after blipping the throttle is a classic sign that the carbs are out of synch.

[kerryb]

Yeah, it sucks to get old, but at least I can play with bikes more!
So last night I pulled the carbs to fix the idle air jets, happened to have the right drill bit. Good thing I checked the other jets cause one of my slides was a little sticky. Also took the synch adjusters apart to polish the mating surfaces. Then a bench synch, and put them back on. Today I'll run it enough to reset all the vacuum synch procedures again and reset the idle mixture for the new jet sizes. This afternoon will either be delightful...or another setback!

[kerryb]

It was almost delightful! Bench synch was useless ( rushed) but vacuum synch is spot on. Idles quite low and smooth, but hiccups once in a while. Flat spot off idle is much improved. Waiting for oem points to arrive because it just isn't smooth enough yet, and I think it's worth a try. In the mean time I'll check the valve clearances again. Thanks for the suggestions Redglbx.

I was blessed a couple years ago with the gift of the honda synchronizer tool. A screwdriver inside a hex socket, makes synch adjustments easy. Now I just need to remember which way to turn it...I gotta make a cheat sheet.

[gltriker]

hiccups, flat spot off idle, set pilot screws at 3 turns out from lightly seated...

how low and smooth is the engine idle speed set at?

I'm also interested to know if the 4 synchronizing gauges are still installed when the engine occasionally hiccups. If yes, before you set the pilot screws at 3 turns out from lightly seated, does any one of the 4 vacuum gauges momentarily register a pressure spike when a hiccup is noted?

Thank you

[kerryb]

I'll have to check the gauges, but it will be after new tec points go in. Put it back together tonight because the weather might allow a test drive tomorrow.
The mixture screws are at 2 1/2 turns out now, I'll try 3 on the next test session.
Thanks for the suggestions

[redglbx]

Kerry, the biggest “fix” I’ve found is to replace the idle airjets in the brass elbows from #115’s to #110’s, it will richen things a bit right where you want it. You can get new jets from PJ’s Motorsports or Jets-R-Us. You can get pretty much any jet you want for these bikes from them.

As a side note, I do not or recommend ever drilling jets, it is a bad practice. Years (many) ago I read a article by Holley where they showed the differences between drilling a jet and replacing it with a properly sized jet, the differences were dramatic, I don’t drill jets, it is really bad for precisely controlling the fueling, I know lots of people have done it but it is not a good thing, my .02

Otherwise it sounds like you’re getting there, hope you get to take that bike for a serious ride soon, they are quite special when they’re running right, enjoy !

[taunusrainer]

Normally if a bike does not run as it should, my method is:
-check for air leaks
-check spark plugs and timing
-check valve clearance
-check pilot fuel jets/idle screw.
In this order.

[kerryb]

Normally if a bike does not run as it should, my method is:
-check for air leaks
-check spark plugs and timing
-check valve clearance
-check pilot fuel jets/idle screw.
In this order.

Thanks, trying again today.