Missing or Bogging at High RPMs

If it's broken or just needs tweaked

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Sat Jul 19, 2014 3:38 pm

I wish! I still don't know if it's fuel or ignition causing the problem.

Right now I'm waiting on a replacement spark advancer part to continue troubleshooting.
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

Ejedmond2
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Re: Missing or Bogging at High RPMs

Postby Ejedmond2 » Sat Jul 19, 2014 7:33 pm

My vote is carb related, you're either running rich or lean at that range. My 650c bogged a bit at that range but since I put a high flow filter and jets in it I've never had that problem. My suggestion if possible, kinda need an open street and neighbors that don't get annoyed. Is to get it to that point in the mid range shut it off coast or push to some where you can check plugs. Ignition I don't think would be the problem here

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Sat Jul 19, 2014 8:25 pm

It would seem so to me too, but the bike is BONE STOCK. How did it run for 14k miles in this condition?

How can it rev to red-line in neutral, but bog down under load?
I think it's fuel too but I don't see how, if it's completely stock. I took off the air filter cover, no difference. Shouldn't that have changed something? That's why I'm going through everything ignition-related, and still asking questions.
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

cb650
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Re: Missing or Bogging at High RPMs

Postby cb650 » Sun Jul 20, 2014 11:18 pm

I got a shaft. Pulled it out of a engine. PM or email me your addy. cb650@juno.com
It is a mystery why the bikes ran but now are air starved.
But that does work on some bikes. And it is the easiest thing to try.
Some one here or on sohc4 just tried it and it worked on his 81.
Also don't forget to try new plugs. even if yours are new. If they get fouled sometimes they don't clear up.
Did you clean the tank out?!?!?!?!

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Mon Jul 21, 2014 1:19 am

Also put in new plugs. No change.

PM sent...
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

cb650
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Re: Missing or Bogging at High RPMs

Postby cb650 » Mon Jul 21, 2014 8:30 am

Did you clean the tank out?!?!?!?!

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Mon Jul 21, 2014 12:41 pm

did that too, no cover on the air filter.

My threads are all over the place...I suppose when I get back through the ignition system with the new advancer shaft, I'll start over again.

At least the bike is rideable around town....
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

cb650
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Re: Missing or Bogging at High RPMs

Postby cb650 » Mon Jul 21, 2014 4:38 pm

I just posted that so you know it does work. Actually I've seen it work on more nitehawks than anything else. As old as these bikes are it can end up being anything. Get your part out in the morn.
Did you clean the tank out?!?!?!?!

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Mon Jul 21, 2014 4:53 pm

Since running without a cover on the air filter made absolutely no difference, that was why I began going through the ignition system.

The bolts and screws have all been boogered up with someone messing around, so it makes sense to go back and ensure that everything's up to spec.
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

cb in alaska
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Re: Missing or Bogging at High RPMs

Postby cb in alaska » Mon Jul 21, 2014 10:06 pm

Can't wait to see what the issue is because I'm having the same exact problem and it sucks. Is your bike puffin black smoke and running rich like mine?

jcasey007
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Re: Missing or Bogging at High RPMs

Postby jcasey007 » Tue Jul 22, 2014 4:37 pm

easy check to see if running lean, when up to temp, riding along and obviously trying to get over 5000 rpm, pull the choke out, if lean it will pick up for a few seconds and then likely bog down = lean mixture, if it makes it run worse, the mixture is rich and will continue to degrade.

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Wed Jul 30, 2014 9:08 pm

I got the replacement shaft. Thanks so much CB650!!!

Obviously can't start the bike, likely have to yank carbs again.

But the plugs are WHITE. I don't see anything wrong with the ignition anywhere, and I would have to borrow a timing light to go any further.

I understand that when doing a plug chop (is that what y'all call it too?) you can't run the bike after reaching the place where the problem occurs. But these plugs brought me home and they're almost as white as new. One of them is a little brown on one side only. Nobody would call these plugs tan, they're white.

That's super-lean, right? If the whole setup is stock, what would cause this lean mixture? I just can't find any intake leaks anywhere at all, stock filter...maybe the chucklehead I bought it from put in smaller jets? Why would anybody do that?
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Wed Jul 30, 2014 9:11 pm

Also, when going through the ignition, I saw that the battery drain tube had slipped off and started to rust, so I pulled the battery to clean all that up and route the drain properly. The positive lead was corroded down into the clamp, so I pried it away and re-soldered it clean. Of course that made me check the other end at the starter solenoid and I found that my main fuse was not a fuse. It was a few strands of copper wire between the two screws on the solenoid. Ridiculous.

I wired in a proper fuse holder, but I'd like to make sure this is a 30 amp fuse?

And, assuming I got the fuse right, is there ANY chance that a corroded positive lead would allow the bike to start well and idle well, but miss and bog at 5.5k RPM?
Jenn in "Jaw-juh"
1982 CB650 Nighthawk

MiGhost
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Re: Missing or Bogging at High RPMs

Postby MiGhost » Thu Jul 31, 2014 5:20 pm

Yes. The fuse on the solenoid is 30 amp.
Corroded battery, and ground cables will keep the coils from getting full voltage so yes that could be a possible cause of bogging at hgher rpms.
~ Ghost

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coffee_brake
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Re: Missing or Bogging at High RPMs

Postby coffee_brake » Thu Jul 31, 2014 9:21 pm

Hot diggity! Another windmill to joust!
Jenn in "Jaw-juh"
1982 CB650 Nighthawk


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