trying to get my bike running

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Ben
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trying to get my bike running

Ben
i have just recently bought a 1972 honda 750 cb that has been sitting for 11 years, but is still in good shape. When i got it home we got it to turn over once and since then it hasnt. i have replaced the battery, rebuilt the carbs,replaced the spark plugs, and replaced the coils. i have also checked and cleaned the little round filter that seperates my fuel tank from my fuel lines. When i try to start it, it sounds like it wants to turn over, but it just wont . i have tried manual starts, compresion starts, and just the regular ignition starts and still nothing. i am new to the bike world ,just learning as i go, so any help or advice would be greatly appreciated. thank you.
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Re: trying to get my bike running

TOOLS1
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Welcome to the forum. I am going to assume that the engine is cranking over, so the first thing to check, for is spark. If, you have spark then check, for gas getting into the cylinders. After this we will know more about how to proceed.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
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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)
Ben
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Re: trying to get my bike running

Ben
its has an electronic ignition and no points. the top of the piston looks clean and dry. spark plug has black soot(which wipes off easily) im assuming all the back fire noises might be the cause of the soot. the way the fuel lines are set up is one fuel line comes from the gas tank and goes to a T between carb 4 and 3 and the other fuel line come to a T between 2 and 1. i dont believe i have messed up the coil wires. Cyclinder one is on the far right as you are sitting on the bike. I have a good spark off all four spark plugs. i have 98 pounds of cylinder pressure on all four cylinders. As for the fuel, how do you check if fuel is getting to each cylinder?
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Re: trying to get my bike running

mikefootusa
Correct me if I'm wrong...isn't #1 on the left as from sitting on the bike?
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: trying to get my bike running

shinyribs
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You're correct Mike. Number 1 is on the clutch lever side. If your plugs look wet then they have fuel on them. if they are sooty as you describe,there must be fuel present to create soot. If you are experiencing backfires I would consider checking the timing. BUT,since it is a possibility you confused the cylinder numbers,once you correct that it will most likely correct the timing issue,if that is the case. #1 far left sitting on the bike then left to right 1-2-3-4. Try that and let us know what happens. Good luck!
Ben
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Re: trying to get my bike running

Ben
it worked! we just had the spark plugs and coil wires in the wrong spot. thanks a lot guys i really do appreciate it im excited to ride it.
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Re: trying to get my bike running

Lucky 1
In reply to this post by Ben
All machines in the world airplanes,cars,motorcycles everything has the parts oriented as if the operator is standing in the back of the machine looking forward.

Airplane engine on the far left  is #1 engine.
Pilot seat left side #1 seat.

Motorcycle engine cylinder on the far left is #1.


See what I mean.
On a Roadstar Adventure.
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Re: trying to get my bike running

Piute
ford n chevy ?
                            1977 CB750 F2 Super Sport
<LET THOSE WHO RIDE DECIDE><RIDE TO LIVE-LIVE FOR JESUS> 
Native American from central Cal,  Kickstand UP in S.W.Missouri,
                                       
 
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Re: trying to get my bike running

mikefootusa
In reply to this post by Ben
Hey Ben...glad you got it running!
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: trying to get my bike running

shinyribs
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Ford uses the right front cylinder for #1. Leave it to them,huh? It's because when looking at the motor from the front that cylinder protrudes the furthest forward,therefore its the first cylinder to get to. Sometimes that method is used as well.

Regardless...woo hoo !  It lives! Good feeling ,huh?
Ben
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Re: trying to get my bike running

Ben
its a great feeling. this is my first bike so im so excited to get it up and running! thanks again guys.
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Re: trying to get my bike running

LukeM
Administrator
Glad you got it going.  Nice feeling, isn't it?

Now you get to take some time to get to know your bike.  Listen to all the little noises it makes.  How does it accelerate: smoothly, jerks a bit, stumbles, runs out of breath at 6000 rpm?  Are the brakes pulsing or feeling soft? Take it into a turn, does it wiggle or wander, maybe step out on you? How are the tires? Do they have decent grip? Turn signals working well?  Instruments bright enough?  Any leaks or drips? Chain need adjustment?

This is the fun part...finding all those little things that need occasional attention. If the core of the machine (engine and drivetrain) are working well, then you're in good shape.

By the way, I know a guy in KC who's got LOTS of cycles for parts and stuff.  Maybe you've heard of him...he posts to this forum once in a while.

Good job, Ben.  Now you get to help the next guy, be it here, or on the road somewhere. Be careful.
Luke M
Used to have a 1979 CB750L, sold it as a parts bike, now riding a slightly modified 1984 VT700C. Network/Field Engineer. Central OH, USA, Earth, Sol System, Milky Way Galaxy, Universe.