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TOPIC: Out of ideas.
#1011232
Jaybo (User)
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Out of ideas. 2 Months, 1 Week ago  
OK, Here is what I've done.

BAK, with needle, Pumpless, Grizzly valve and seat, 170/37.5 jets, 2 turns out on PMS. Curts manifold and new O-rings, 3" HK's. Float level is @ 5mm measured at the back side.

I've blown out the carb multiple times, stuff comes out the other side when I do, tried needle in the middle and then bottom notch - no difference, fuel is very obviously spraying into the carb, (fuel is fresh), I checked for air leaks and even polished the surface on the jugs so I knew they were clean, reinstalled with a light coat of grease, rechecked, no leaks. It will start easily with the choke out and high idles just fine. If you give it gas it will spit and sputter and you can work it into more throttle but only with the choke out. Any gas without the choke and it dies. Does not want to idle with the choke off. Fuel flow is good, no additional filter except for the in tank one.

I'm stuck and not sure where to go from here.
 
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#1011243
Aussie John (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
This sounds like mission impossible and the world might end tomorrow at 1300, lucky for some, I don't see a big problem here at all, the carb runs in the 37.5 for most of its life as in idle and lower speeds so that is where I would check, it maybe that if it has sat for some time or shitty fuel there might be some corrosion in the hole that feeds that jet ? if there is then there will be corrosion elsewhere and you might need small piece of wire to poke in there to clean it out, or gas welding tip cleaners, soaking in a cleaner will help, that float level is from the join in the bowl? I had a small carb that had gummed so bad I bought a new one ($25) easier than fixing , hope this helps John
 
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#1011250
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Re:Out of ideas. 2 Months, 1 Week ago  
Jaybo wrote:
OK, Here is what I've done.

BAK, with needle, Pumpless, Grizzly valve and seat, 170/37.5 jets, 2 turns out on PMS. Curts manifold and new O-rings, 3" HK's. Float level is @ 5mm measured at the back side.

I've blown out the carb multiple times, stuff comes out the other side when I do, tried needle in the middle and then bottom notch - no difference, fuel is very obviously spraying into the carb, (fuel is fresh), I checked for air leaks and even polished the surface on the jugs so I knew they were clean, reinstalled with a light coat of grease, rechecked, no leaks. It will start easily with the choke out and high idles just fine. If you give it gas it will spit and sputter and you can work it into more throttle but only with the choke out. Any gas without the choke and it dies. Does not want to idle with the choke off. Fuel flow is good, no additional filter except for the in tank one.

I'm stuck and not sure where to go from here.


Are you letting the bike warm up, before shutting the "ENRICHER" off? Are you running the "Enricher" at about half out, until the bike has warmed up enough to idle and accept throttle without it?

If you roll the throttle on a cold start, when the "ENRICHER" is out and the motor needs the rush of extra fuel the "ENRICHER"provides, you lose the vacuum that makes the "ENRICHER" work. Roll the throttle, and the throttle plate in the carb throat opens up, and the vacuum disappears.


The needle should be in the 4th groove from the blunt end. There should be a fat plastic spacer and a silver washer under the clip(at least until it is running properly, and you want to start tweaking)

Is the hot idle set at 900rpms?

If it is doing it when the bike is warmed up, then I'm guessing you have a blockage in the Pilot circuit still. Have you looked real hard in the Pilot jet itself? It just takes a little speck of something lodged in the jet or passageway, to block the fuel you need in the Pilot circuit.
 
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Last Edit: 2017/05/20 08:24 By SKWEARpeg.
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#1011255
LDofDC (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
Did you remove the small screen in the inlet?

Also is the accelerator squirter working?
 
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#1011258
cike (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
Just a thought. There is a white flat cover on the side of the carb about the
Size of a .50 piece, does it look burnt or cracked. A crack here can make the bike act like it is out of gas when you try to let out the clutch
 
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owning a motorcycles not a matter of life or death, its much more important than that
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#1011261
Jaybo (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
This sounds like mission impossible and the world might end tomorrow at 1300, lucky for some, I don't see a big problem here at all, the carb runs in the 37.5 for most of its life as in idle and lower speeds so that is where I would check, it maybe that if it has sat for some time or shitty fuel there might be some corrosion in the hole that feeds that jet?

Might end if I keep hitting my head against the wall! Carb was working fine before, it has been off the bike so is not at all gummy. The 37.5 is brand new, no corrosion and I have blown out the passages 3X now and is spraying out the other side.

Are you letting the bike warm up, before shutting the "ENRICHER" off? Are you running the "Enricher" at about half out, until the bike has warmed up enough to idle and accept throttle without it?

It will barely run without the Enricher on. I do let it get good and warmed up and when I shit it off it is at best a stumbly idle. It won't take any throttle without dying.

The needle should be in the 4th groove from the blunt end. There should be a fat plastic spacer and a silver washer under the clip(at least until it is running properly, and you want to start tweaking)

OK, this one may be my problem. I have no plastic spacer. The needle is really that high? How thick is the spacer?

If it is doing it when the bike is warmed up, then I'm guessing you have a blockage in the Pilot circuit still. Have you looked real hard in the Pilot jet itself?

I've looked at it so many times it stopped blushing. I've blown out the passageway with carb cleaner and it does not appear to be blocked. I will do it again though.

Did you remove the small screen in the inlet?
Also is the accelerator squirter working?


Yes and Yes.

There is a white flat cover on the side of the carb about the Size of a .50 piece, does it look burnt or cracked?

It looks fine and was working fine before teardown. I will inspect it though.

Off to tear it apart again...
 
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#1011267
Jaybo (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
SKWEARpeg wrote:
The needle should be in the 4th groove from the blunt end. There should be a fat plastic spacer and a silver washer under the clip(at least until it is running properly, and you want to start tweaking)[/quote]

Huh. Whodathunk. It is much better and although I have a stumble off idle I can roll it on, and it doesn't die. A little plastic spacer... Why would they just not make a proper needle that doesn't need to use a spacer? I'm thinking now I need to go up a size on the pilot and drop the needle a hair.
 
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#1011268
SKWEARpeg (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
Jaybo wrote:
SKWEARpeg wrote:
The needle should be in the 4th groove from the blunt end. There should be a fat plastic spacer and a silver washer under the clip(at least until it is running properly, and you want to start tweaking)


Huh. Whodathunk. It is much better and although I have a stumble off idle I can roll it on, and it doesn't die. A little plastic spacer... Why would they just not make a proper needle that doesn't need to use a spacer? I'm thinking now I need to go up a size on the pilot and drop the needle a hair.[/quote]

That's kinda what they did. The stock needle only has a single groove. The spacer and silver washer, actually set the proper elevation. The silver washer is actually a shim. Without a multi groove needle, you would buy a package of shims and start adding them under the clip until the mid range was rich enough. Without the fat spacer, you're so lean on the Needle even at the 4th from the top(blunt end), you are not getting the fuel you need from the Main to make the transition.
Heck. Without the fat spacer, you could probably set the clip in the 5th or 6th groove, and be closer to right.

Leave the Pilot at a 37.5 with a 1600, and move the clip down if you don't have the fat spacer anymore. What happened to it? Is it still in the slide?
 
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#1011271
Jaybo (User)
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Re:Out of ideas. 2 Months, 1 Week ago  
Oh, I found the spacer, I took it out when I replaced with the adjustable needle thinking it was not needed. What I meant about them making a replacement needle was for the BAK kit so you would not need to use a spacer. Right now I have it in the 4th groove from the top (richer) with the spacer and it is still stumbling. I will put in the last groove and see if it clears up, or is a little better. That's why I thought a richer pilot and a lower needle would give me more adjustment.

Now I am chasing a lighting circuit short that is stopping me from putting it back together. Ugh.
 
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#1011323
SKWEARpeg (User)
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Re:Out of ideas. 2 Months ago  
If your in the 4th groove, and it is still stumbling, you still have a problem. How is the idle? Is it set to low? Any chance you have an air leak? AIS vacuum port not sealed properly? Is there an exhaust leak past the exhaust gaskets?

I answered your PM first, before I read this. Since you're in the very bottom groove with the needle, then something else is happening. In the PM, I asked about the brand of Needle. Is it a Barons or DJ, or a Speedstar?
 
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Last Edit: 2017/05/21 05:35 By SKWEARpeg.
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