1998 Honda CB 750 NIGHTHAWK - WONT START

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1998 Honda CB 750 NIGHTHAWK - WONT START

richardvm
I dropped by bike and after that is started to run rough - so i took off carbs and cleaned them out - put back together - and it wont start- there is petrol on spark plugs and good spark on all 4 plugs.When you spin it trying to start it - all the engine oil disappears and it back fires and smokes - but will not even show a hint of starting or taking?when you leave it - the oil returns to normal on dipstick?
Help Richard
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Re: 1998 Honda CB 750 NIGHTHAWK - WONT START

TOOLS1
Administrator
What you describe is the symptoms of an engine being 180* out of time. Did you do any work on the ignition system, or wires?
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: 1998 Honda CB 750 NIGHTHAWK - WONT START

richardvm
no - only cleaned out carbs
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Re: 1998 Honda CB 750 NIGHTHAWK - WONT START

TOOLS1
Administrator
Did you disconnect any wires when you removed the carbs?
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: 1998 Honda CB 750 NIGHTHAWK - WONT START

richardvm
only the snap connectors under the petrol tank - which are impossible to connect incorrectly
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Re: 1998 Honda CB 750 NIGHTHAWK - WONT START

TOOLS1
Administrator
Other then the engine being 180* out of time, there is no other reason why it would not start, and just pop, and backfire. Humor me and reverse the two wires on the negative side of the coils (the ones going to the CDI) and give it a try. Also check the plug wires. The two on the left coil go to the two outside plugs (#1, #2) the wires on the right coil go to the two inside plugs (#2, #3).
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: 1998 Honda CB 750 NIGHTHAWK - WONT START

richardvm
I have check wires as suggested - still nothing -have sent to workshop and will advise what they found
many thanks Richard