Help with carb setup

I have been having issues getting the bike fired up in the morning.
1. Bike is hesitant to start and often starts and dies out a few times until it's warm.
2. Idle is all over the place usually lo rpm until it gets warm and then the idle runs a little high I usually adjust the throttle to run around 1000 rpm at idle.
3. Carb sounds like it is spitting "cough" until it is warm.
I have a xxx carb running .072 primary jet with a 29.5 intermediate.
Running an aftermarket filter with a k&n fikter "not a spike"
To me plugs are running rich rear plug more than the front which might explain the blue flames from the rear exhaust on decel or high rev.. Too much fuel..
I know all of this has been posted before... But can never get it dialed in ... Runs awesome once it's warmed up but runs shitty until then
 

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Sven

Well-Known Member
Bike is hesitant to start... and dies out til it's warm.
I'll try to back up what baylor says. When I leak, I am just like electricity. I find the shortest path to zero-out back to 14.7 psi. So instead of pulling gas out of the jet tubes, the intake manifold is closer to the intake valve and the speed of air into that manifold crack; throws off the fuel to air ratio; becomes too lean and hard to start.

the idle runs a little high
Way [way] back when when I was mowing the lawn, I remember how the engine began to rev up real high and then stop running as it ran out of gas. I thought from then on, if I could only tune to that high rpm and run that lean, but do we sort of see the air tunnel becoming fueled with less fuel as the gas runs out of the carb? Same sort of air effect, i.e., less fuel beginning to peak in rpm. Make sense?

which might explain the blue flames from the rear exhaust on decel or high rev.. Too much fuel.
On lift, the engine is still pulling gas out of the carb. However, like a dozen eggs, one exploding egg hits another egg and the flame front continues. Imagine less fuel or less eggs next to each other and it's hard to light that lean of a mix. So while the carb has closed, even more fuel enters, does not explode enough, hangs in the muffler; the throttle opens, the flame leaves the exhaust port; lights that unspent; out comes a flame.

Valve guide wise, you see a vehicle head down a hill and on lift, that valve is still opening, the fuel is washing the valve stem, the oil mixed with gas or flame front lights off that [lift] ]hanging in the muffler;' a puff of smoke comes out and clears up upon throttling up. That guide still leaks every time the valve opens.

Runs awesome once it's warmed up but runs shitty until then
Look at how the jetting [when warm] seems to run fine; seat of the pants wise. See how the heat may close off some of that air leak under expansion, being in a, 'lean is mean' kind of setting.
 
I'll try to back up what baylor says. When I leak, I am just like electricity. I find the shortest path to zero-out back to 14.7 psi. So instead of pulling gas out of the jet tubes, the intake manifold is closer to the intake valve and the speed of air into that manifold crack; throws off the fuel to air ratio; becomes too lean and hard to start.


Way [way] back when when I was mowing the lawn, I remember how the engine began to rev up real high and then stop running as it ran out of gas. I thought from then on, if I could only tune to that high rpm and run that lean, but do we sort of see the air tunnel becoming fueled with less fuel as the gas runs out of the carb? Same sort of air effect, i.e., less fuel beginning to peak in rpm. Make sense?


On lift, the engine is still pulling gas out of the carb. However, like a dozen eggs, one exploding egg hits another egg and the flame front continues. Imagine less fuel or less eggs next to each other and it's hard to light that lean of a mix. So while the carb has closed, even more fuel enters, does not explode enough, hangs in the muffler; the throttle opens, the flame leaves the exhaust port; lights that unspent; out comes a flame.

Valve guide wise, you see a vehicle head down a hill and on lift, that valve is still opening, the fuel is washing the valve stem, the oil mixed with gas or flame front lights off that [lift] ]hanging in the muffler;' a puff of smoke comes out and clears up upon throttling up. That guide still leaks every time the valve opens.


Look at how the jetting [when warm] seems to run fine; seat of the pants wise. See how the heat may close off some of that air leak under expansion, being in a, 'lean is mean' kind of setting.
Holy shit! Talk about hard to understand ? You win!
Thanks
 

BadDawg Bill

Well-Known Member
I'll try to back up what baylor says. When I leak, I am just like electricity. I find the shortest path to zero-out back to 14.7 psi. So instead of pulling gas out of the jet tubes, the intake manifold is closer to the intake valve and the speed of air into that manifold crack; throws off the fuel to air ratio; becomes too lean and hard to start.


Way [way] back when when I was mowing the lawn, I remember how the engine began to rev up real high and then stop running as it ran out of gas. I thought from then on, if I could only tune to that high rpm and run that lean, but do we sort of see the air tunnel becoming fueled with less fuel as the gas runs out of the carb? Same sort of air effect, i.e., less fuel beginning to peak in rpm. Make sense?


On lift, the engine is still pulling gas out of the carb. However, like a dozen eggs, one exploding egg hits another egg and the flame front continues. Imagine less fuel or less eggs next to each other and it's hard to light that lean of a mix. So while the carb has closed, even more fuel enters, does not explode enough, hangs in the muffler; the throttle opens, the flame leaves the exhaust port; lights that unspent; out comes a flame.

Valve guide wise, you see a vehicle head down a hill and on lift, that valve is still opening, the fuel is washing the valve stem, the oil mixed with gas or flame front lights off that [lift] ]hanging in the muffler;' a puff of smoke comes out and clears up upon throttling up. That guide still leaks every time the valve opens.


Look at how the jetting [when warm] seems to run fine; seat of the pants wise. See how the heat may close off some of that air leak under expansion, being in a, 'lean is mean' kind of setting.
Sounds like my Ex telling the judge how I'm such a low life....
 

Sven

Well-Known Member
The short and sweet... poor idle when cold, runs good when hot: Spray brake clean at the manifolds. Engine stalls or revs up = Leak.

Withoutheoryou're Fuckedover at the dealer drive. You gave a good diagnosis at the drive, let me write that up. We'll call you with the problem and any safety issues before we have our personal ride your pile of problems a machine has [in general].

Ring-Ring!
Hello, Mr. Deepsea, it was a circuit problem at the carb. So new intake gaskets and a bowl gasket, the diagnosis included, it comes to cha-ching and your chain is wearing out and the tire has Abe's bald spot showing with the penny test in the threadepth. Would you like that upsell taken care of now or we make note it's sketchy on your work order?

Why the intake gaskets? We break a seal we change with new memory, not some collapsed rubber and cause a leak... see the cashier on your way out, Bubbles.
 

chubs

Guru
The short and sweet... poor idle when cold, runs good when hot: Spray brake clean at the manifolds. Engine stalls or revs up = Leak.

Withoutheoryou're Fuckedover at the dealer drive. You gave a good diagnosis at the drive, let me write that up. We'll call you with the problem and any safety issues before we have our personal ride your pile of problems a machine has [in general].

Ring-Ring!
Hello, Mr. Deepsea, it was a circuit problem at the carb. So new intake gaskets and a bowl gasket, the diagnosis included, it comes to cha-ching and your chain is wearing out and the tire has Abe's bald spot showing with the penny test in the threadepth. Would you like that upsell taken care of now or we make note it's sketchy on your work order?

Why the intake gaskets? We break a seal we change with new memory, not some collapsed rubber and cause a leak... see the cashier on your way out, Bubbles.
:hi: Damn, Sven; you were headed right on up the road with the first sentence, but then you hung a sharp right with those word salads:oldconfused:. I did like the conversation with the dealer,:oldwtf: that was about the truth. :old2: By the way, you ever gonna get that bike up? come on man, time to ride!:chopper:
 
The short and sweet... poor idle when cold, runs good when hot: Spray brake clean at the manifolds. Engine stalls or revs up = Leak.

Withoutheoryou're Fuckedover at the dealer drive. You gave a good diagnosis at the drive, let me write that up. We'll call you with the problem and any safety issues before we have our personal ride your pile of problems a machine has [in general].

Ring-Ring!
Hello, Mr. Deepsea, it was a circuit problem at the carb. So new intake gaskets and a bowl gasket, the diagnosis included, it comes to cha-ching and your chain is wearing out and the tire has Abe's bald spot showing with the penny test in the threadepth. Would you like that upsell taken care of now or we make note it's sketchy on your work order?

Why the intake gaskets? We break a seal we change with new memory, not some collapsed rubber and cause a leak... see the cashier on your way out, Bubbles.
Will post more once I get it dialed in, unfortunately most of the time if it starts and runs I just ride and forget about the bs in between.
Thanks for the help just wish you would post more straight forward , your diagnosis is most often hard to read. Simple and to the point is easier to understand!
 
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