81 CB 750C cam switch...

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81 CB 750C cam switch...

ArjaiC
OK, I am hoping some of you are familiar with my issue/want.

Years ago, I had a friend with a 750 Nighthawk, dual cam, with the same engine I have. His dad, one winter, switched out the camshafts with one from a 900cc engine. I rode the bike often, his girlfriend didn't enjoy riding it and my girl loved it. We would often switch vehicles, sometimes for weeks at a time.

So, after his dad flipped the camshafts, that bike had a new set of balls.

My question is, what all does this entail, do the carbs need new jets and re-sync?

If it's not to laborious,I am hoping to have a local shop help me with this. I'd ask them but, since I know nothing about it, they might scam me on the price.

Does anyone here know the procedure and maybe the hours it would take to do?

Thanks!
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Re: 81 CB 750C cam switch...

TOOLS1
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Just remove the 750 cams, bolt in the 900 cams, and adjust the valves. Ride it and do a plug chop to see if it might need a jetting change, but I doubt it will. Should take around 4 hours.
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: 81 CB 750C cam switch...

ArjaiC
I don't remember, but, when it was changed, or when I change it, does it put a lump in the idle? Or, is that it brings the torque up in the 3000rpm range?

It has been so long ago, I just remember it was like a fresh engine.

Also, I am hoping you are right, about the carbs. I don't remember his dad saying anything about the carbs.

Another thing, I have not bothered to check, yet, what is a good price for a set of camshafts, that are usable!
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Re: 81 CB 750C cam switch...

ArjaiC
Also, any difference in camshafts, or rather, lobe heights, between 900c of 900f camshafts?

Thanks...
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Re: 81 CB 750C cam switch...

ArjaiC
In reply to this post by TOOLS1
1981 HONDA CB900 C CAM SHAFTS W/ GEARS

HONDA CB 900 C 10 SPEED SPECIAL PAIR CAM SHAFTS

1982 honda cb 900 f camshafts and gears CB900F

80 81 Honda CB900C Intake & Exhaust Camshafts & Gears 81 CB900F


1982 honda cb 900 f camshafts and gears

I put these in my ebay watch list. Pricing is all over the place but, I am wondering if you could use your profession eyes and tell me if there is a dog in there or, which is best.

Thank you for all you do and the help with my question!
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Re: 81 CB 750C cam switch...

TOOLS1
Administrator
The 3rd set has some discoloration on two of the lobes. The others (for what I can see) look pretty good. There is not any difference between "C, K, and F" cams. As for "lope" these engines do not idle low enough to get that "lope" like a car engine.
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)