Number 2 cylinder not heating up properly.

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Number 2 cylinder not heating up properly.

Luccondon
Hi All,

Just changed out spark plugs, caps and coils for all cylinders on my 73' cb750, but the #2 cylinder is not heating up to a very high temp (I assume that this is due to it not getting spark....).

Anyone have any ideas?  I just had the carbs synced recently, along with the tappets adjusted as well.  So I don't want to say it is the mixture.... But then again this is my first bike and I have only had it for 6 months.

Any ideas on the 2nd cyclinder would be greatly appreciated!!

Thank you all so much,
Lucas
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Re: Number 2 cylinder not heating up properly.

TOOLS1
Administrator
Try switching the #2 and #3 plug wires and see if the problem moves to the #3 cylinder. If it moves, it is a plug wire problem. If it does not move, switch the #2 spark plug with the #3. If the problem moves, it is the spark plug. If it does not move, it is a carb problem. Most likely plugged pilot jet.
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: Number 2 cylinder not heating up properly.

Luccondon
Thanks TOOLS,

Made the switches and found that the plug on #2 was fouled and black (which is only about 120 miles old....).

I will switch out for a new plug and see if it continues.

Thanks,

Lucas,

Sent from my iPhone (Please excuse typos and brevity!)

On Jul 15, 2016, at 19:02, TOOLS1 [via Honda CB750'S] <[hidden email]> wrote:

Try switching the #2 and #3 plug wires and see if the problem moves to the #3 cylinder. If it moves, it is a plug wire problem. If it does not move, switch the #2 spark plug with the #3. If the problem moves, it is the spark plug. If it does not move, it is a carb problem. Most likely plugged pilot jet.
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)



If you reply to this email, your message will be added to the discussion below:
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Re: Number 2 cylinder not heating up properly.

Luccondon
In reply to this post by TOOLS1
I think it may be the jet, as you say.  Since I just replaced the plug and there is no difference.  It warms up, but I can still grab it after riding for 5 minutes.

I had the carbs cleaned out by a local mechanic when I got the bike around 6 months ago, so I would hope that there isn't going to be another need for them to be taken off.  Especially since I have already sunk a good few hundred into getting it clean after the previous owner.

Lucas,

On Jul 15, 2016, at 19:02, TOOLS1 [via Honda CB750'S] <[hidden email]> wrote:

Try switching the #2 and #3 plug wires and see if the problem moves to the #3 cylinder. If it moves, it is a plug wire problem. If it does not move, switch the #2 spark plug with the #3. If the problem moves, it is the spark plug. If it does not move, it is a carb problem. Most likely plugged pilot jet.
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)



If you reply to this email, your message will be added to the discussion below:
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NAML
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Re: Number 2 cylinder not heating up properly.

Re-run
Administrator
I recommend doing the cleaning yourself this time. It seems to be an easy clean. Pull the carbs off and remove the jets. As long as you don't screw with the slides, you won't have to resync. Likely just have holes plugged up. It is possible that the float is hung up and not letting enough fuel into the bowl. So just make sure the float seat is clean and the needle moves freely.
The ride IS the adventure. The destination is just to get gas!
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Re: Number 2 cylinder not heating up properly.

TOOLS1
Administrator
In reply to this post by Luccondon
Did you actually try the wires/spark plug in/on the other cylinder, or just pull the plug and see it was dirty?
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: Number 2 cylinder not heating up properly.

Luccondon
I tried both things that you suggested.  Switched around the wires to other cylinders and there was no change.

On Wed, Jul 20, 2016 at 10:06 AM, TOOLS1 [via Honda CB750'S] <[hidden email]> wrote:
Did you actually try the wires/spark plug in/on the other cylinder, or just pull the plug and see it was dirty?
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)



If you reply to this email, your message will be added to the discussion below:
http://honda-cb750-s.456789.n3.nabble.com/Number-2-cylinder-not-heating-up-properly-tp4060950p4060979.html
To unsubscribe from Number 2 cylinder not heating up properly., click here.
NAML

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Re: Number 2 cylinder not heating up properly.

TOOLS1
Administrator
OK. Then you must have a carb problem. Try cleaning the jets.
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: Number 2 cylinder not heating up properly.

Luccondon
I will do that like you have both advised.

I have to admit, this is my first bike and I have never been closer to the inside of a carb than youtube videos and these forums so it's a little daunting!
Is there a good tutorial that anyone could point to?

Thanks,
Lucas

On Wed, Jul 20, 2016 at 3:00 PM, TOOLS1 [via Honda CB750'S] <[hidden email]> wrote:
OK. Then you must have a carb problem. Try cleaning the jets.
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)



If you reply to this email, your message will be added to the discussion below:
http://honda-cb750-s.456789.n3.nabble.com/Number-2-cylinder-not-heating-up-properly-tp4060950p4060983.html
To unsubscribe from Number 2 cylinder not heating up properly., click here.
NAML

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Re: Number 2 cylinder not heating up properly.

TOOLS1
Administrator
The round top carbs that your bike should have are the simplest carbs you could find. Just flip the wire that holds the float bowl on and lift the bowl off. The two jets will be right there. You will want to get a guitar string to clean them. The small jet is the pilot jet, and the one that is causing your problem. However I will caution you on one thing. The 43 year old intake boots are going to be hard from heat and age. You might want to think about replacing them and the clamps. New ones are pretty reasonable on ebay now.
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: Number 2 cylinder not heating up properly.

Luccondon
Just a thought as I am going to bet getting in to this tonight.

Would a clogged pilot jet be the issue behind them not getting hot even
while riding?  Even after taking it through town and on the highway, I come
back and it is still not as hot as the rest (with a new plug and resistor
cap....).

I thought  that the pilot jet only managed fuel flow for the idle and up to 3Krpm?

On Wed, Jul 20, 2016 at 9:06 PM, TOOLS1 [via Honda CB750'S] <
ml-node+s456789n4060987h75@n3.nabble.com> wrote:

> The round top carbs that your bike should have are the simplest carbs you
> could find. Just flip the wire that holds the float bowl on and lift the
> bowl off. The two jets will be right there. You will want to get a guitar
> string to clean them. The small jet is the pilot jet, and the one that is
> causing your problem. However I will caution you on one thing. The 43 year
> old intake boots are going to be hard from heat and age. You might want to
> think about replacing them and the clamps. New ones are pretty reasonable
> on ebay now.
> 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)
>
>
> ------------------------------
> If you reply to this email, your message will be added to the discussion
> below:
>
> http://honda-cb750-s.456789.n3.nabble.com/Number-2-cylinder-not-heating-up-properly-tp4060950p4060987.html
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Re: Number 2 cylinder not heating up properly.

TOOLS1
Administrator
Yes a pilot jet can do that. And actually it does keep working through most of the throttle range, not just off 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: Number 2 cylinder not heating up properly.

Luccondon
Thanks for the heads up.

I will report back with findings from my first carb adventure this weekend.

On Fri, Jul 22, 2016 at 10:53 AM, TOOLS1 [via Honda CB750'S] <[hidden email]> wrote:
Yes a pilot jet can do that. And actually it does keep working through most of the throttle range, not just off 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)



If you reply to this email, your message will be added to the discussion below:
http://honda-cb750-s.456789.n3.nabble.com/Number-2-cylinder-not-heating-up-properly-tp4060950p4060998.html
To unsubscribe from Number 2 cylinder not heating up properly., click here.
NAML