Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

If it's broken or just needs tweaked

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juntjoo
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Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Sun Apr 01, 2018 9:13 pm

Bike was running fine except for some 'clack'ing so I just went in to check the valves and low and behold had to redo them. This time to 10lbs torque per Clymer so nothing gets loose, but now it runs horribly making spitting noises and #1 exhaust is not hot so I re-did idle adjustments per book(quite intricate) and still crappy. Mind you just 24hrs ago I was losing cops with this thing, just had a clacking to it. No vacuum leaks.

So my #1 sync was off but now after adjusting it I can't get it below 1.8krpms.

If I turn idle screws in all the way I can bring down to 1.5krpms.

Checked #1 plug. it's wet, my 1st impression would be from oil.

So I swapped idle screws of #1 with #4, no change.

Tried swapping both main and slow speed jets(only ones I've got) no go.

https://youtu.be/0w09ydPaKac

Lastly I swapped top parts(spring, slide, kidney gasket)with #4 and sprayed into holes. #1 was wet with fuel btw. Again no go. I also tried swapping wires with #4 completely AND just at the plugs. It gets spark definitely. And no change

Probably what you'd expect but just to note, pulling the sync tool tube from #1 causes lots of air to pulse through and have zero effect on idle whereas other cylinders cause engine to bog and very slight air puffing through hole.
82" cb650 Nighthawk

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GeorgeSweety
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby GeorgeSweety » Mon Apr 02, 2018 4:33 am

"If I turn idle screws in all the way I can bring down to 1.5krpms." How many have you got? Shouldn't there be only one idle screw? At this point I would say "Whatever you did, undo it and put it back how it was and don't worry about a little bit of any rattle from a nearly 40 year old engine" :lol:

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Folsoml
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby Folsoml » Mon Apr 02, 2018 4:49 am

juntjoo wrote:Mind you just 24hrs ago I was losing cops with this thing...


Karma. :lol:
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GeorgeSweety
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby GeorgeSweety » Mon Apr 02, 2018 5:50 am

Folsoml wrote:
juntjoo wrote:Mind you just 24hrs ago I was losing cops with this thing...


Karma. :lol:


:lol: :lol: :lol:

juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 9:01 am

GeorgeSweety wrote:"If I turn idle screws in all the way I can bring down to 1.5krpms." How many have you got? Shouldn't there be only one idle screw? At this point I would say "Whatever you did, undo it and put it back how it was and don't worry about a little bit of any rattle from a nearly 40 year old engine" :lol:


Pilot screws? Idle mixture screws? They all need new simpler names. The Bob knob, Larry lever and suzie screws or something.

I know, but all I did was correctly, this time, adjust my clearances. So no clacking! But I'm guessing I tuned the bike to accommodate a bad valve adjustment probably bending a valve or two in the process.

And I'm not paying a mechanic $200+ just to go through all I went through already. Plus the guy I had an appt with today actually for some tires, they specialize in Harleys, not our crazy four bangers, which was apparent talking to them.

So I guess I'm looking at another $300 in gaskets, couple valves, maybe some new tools(?), another week of riding my recumbent bicycle which I love, and don't I gotta pay a machinist to mate a new valve to the seat or something? What special tools will I need? I've got a basic OD micrometer. I'll need to be doing some measurements in there of all parts right, not just my #1 cylinder parts.
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Folsoml
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby Folsoml » Mon Apr 02, 2018 9:40 am

What is the compression like on #1 now?

I notice that you try a LOT of things when something goes wrong. I hope that you are testing things after each adjustment. I think we already discussed "chasing your tail."
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juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 9:51 am

Folsoml wrote:What is the compression like on #1 now?

I notice that you try a LOT of things when something goes wrong. I hope that you are testing things after each adjustment. I think we already discussed "chasing your tail."


Yes we did and I've since tried to check one thing at a time. Last time it was vac leaks(I believe) that fixed my #1&3 cylinders from their non-firing status. So I'll check again and do my compression as you suggest.

Is there any way to check valves save for taking it all apart? I'll do compression again...
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juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 12:09 pm

So far looks BAD

But how do I get this out??

https://imgur.com/a/N3L5q

Why did they make them like this so you could lose the adapters in there?? I should make a harbor freight employee come out here and take it out. Unless I'm doing something wrong. Totally possible lol.
82" cb650 Nighthawk

juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 12:13 pm

And how do you make sure they're snug enough so they're air tight(to give accurate readings) yet not so tight I lose the adapter?
82" cb650 Nighthawk

juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 2:17 pm

https://imgur.com/a/U5EHj

Thank God for these. Barely could fit tho
82" cb650 Nighthawk

juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 4:30 pm

https://imgur.com/a/xNOIU

After adding oil:

https://imgur.com/a/A4rLt

I didn't include #1 as it produces ZERO compression. Explains the cold pipe.

So I guess I'll be quadruple check the clearances. I'll be back...
82" cb650 Nighthawk

juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 5:05 pm

So what am I looking for? Clearances for #1 are perfect. How do I suddenly have zero compression? What's the manual check I can do rotating the shaft? From my view things look like they're moving up and down as they're supposed to. What broke where when and how?
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Folsoml
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby Folsoml » Mon Apr 02, 2018 7:17 pm

At least we've identified the problem. Unless you actually have a hole in your piston, zero compression can only be caused by a valve that is stuck open. I'm feeling like the head is going to have to come off.
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juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Mon Apr 02, 2018 7:52 pm

Folsoml wrote:At least we've identified the problem. Unless you actually have a hole in your piston, zero compression can only be caused by a valve that is stuck open. I'm feeling like the head is going to have to come off.


I also compared #1&4 valve distances from where the rockers connect to the top of the valve cover and for both intake and exhaust they were identical. That would suggest a bent valve then no?
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juntjoo
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Re: Just went in to adjust valves for some 'clack'n and now #1 pipe cool and idles horribly

Postby juntjoo » Tue Apr 10, 2018 3:39 pm

I haven't done anything so far. No time atm but I'm wondering how this could have happened.

Remember that before I went in to redo the clearances it was running great then upon opening it up I find the clearances were too much at least on #1 and another or two cylinders. Adjusted then torqued to spec this time now no compression on #1.

So my question is how does excessive clearance(before I "fixed" clearance on #1) result in GOOD compression?

My guess as I've mentioned previously is that the valve had been bent or something(you tell me, IDK valves) to where somehow less(more clearance =less?) rocker movement not fully opening valve, but adjusted correctly(with bent valve) opens valve too much causing compression loss. Does that make sense? And how much a gap in there is needed to go from adequate compression to suddenly none?
82" cb650 Nighthawk


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