cold hearted CB750SC

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cold hearted CB750SC

mikefootusa
Now that I have the charging system working I find that if I let Helen Black sit overnight she's hard to start.  I have to give her a squirt of ether to get her to fire off.  Once she's warm she starts at the touch of the starter button.

Any ideas?
In 1972 I had to make a choice...quit riding...or quit drinking.  God says it's safe to get back in the saddle now...at least I'm still alive...and feel more alive with the wind in my face!  Now riding "Helen Black"...1982  CB750SC.
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Re: cold hearted CB750SC

TOOLS1
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Pilot jets are plugged.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: cold hearted CB750SC

mikefootusa
This post was updated on .
But I just did a PineSol soak and rebuild (new pilot screw orings, accel pump and air cut diaphragms)  I backed out each of the pilot screws two turns...I have seen somewhere where 2 1/2 turns are recommended.
Going to try backing them out another 1/2 turn tomorrow.
In 1972 I had to make a choice...quit riding...or quit drinking.  God says it's safe to get back in the saddle now...at least I'm still alive...and feel more alive with the wind in my face!  Now riding "Helen Black"...1982  CB750SC.
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Re: cold hearted CB750SC

TOOLS1
Administrator
I am not sure what model bike, you have, but will assume it is a DOHC since, you mentioned the air cut valve.  All the pinesol did was disinfect it. You need to remove the jets, and use a cutting torch tip cleaner in all the holes. Preferably the kind that uses drill bits. Also the screws are not the pilot jets. they are the fuel screws that set the idle.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: cold hearted CB750SC

shinyribs
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In reply to this post by mikefootusa
My bike has pilot jets and idle mixture screws.I dont know if yours is different.My carbs are the round tops.I dont know if what you are calling the pilot screws are the idle mixture screws,but on mine the manual calls for 1-1/2 turns.I found when starting mine cold that it doesnt like full choke at all.It was 40 degrees here today and it wouldnt run on full choke.1/2 choke it did great.
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Re: cold hearted CB750SC

mikefootusa
As it states in the subject line its a CB750SC...'82 Nighthawk.  I removed the carb bank(CV carbs), stripped it down, removed all the jets soaked and cleaned with tip cleaners and compressed air.  Replaced all rubber components, polished the needle seats with Brasso and made sure the check valve in the accelerator pump was clear.  I did have a little rust in the tank and flushed it out several times with gas...using a siphon hose to suck out sediment each time.  Cleaned the petcock tank screen with carb cleaner and compressed air.    Filled the tank with Ethanol free gas and added 1/3 of a can of Seafoam.

Just received the new cup strainer for the bottom of the petcock and plan to install in a while.  II should have done more to clean up the tank after going through all that trouble with the carbs...but I was eager to ride while the weather was nice.  The tank has a good dent in it from the handle bar and I had planned on doing a betterr job of cleaning the inside when I take it of to repair and repaint.
In 1972 I had to make a choice...quit riding...or quit drinking.  God says it's safe to get back in the saddle now...at least I'm still alive...and feel more alive with the wind in my face!  Now riding "Helen Black"...1982  CB750SC.