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Discussion Starter #1 (Edited)
I had the tank off yesterday. Didn't touch the petcock or anything else. Only thing I did was replace the hose running from the carb t-junction to the right air filter box / ear.
Today I took it for a ride. Ran great at first. Better actually, than it did before. Then after about 5 miles it had trouble idling. Tried adjusting the knob a bit, but no luck. It would idle really high when moving and then just die when stationary.
Pulled into a parking lot after a couple miles. It died and would start again. Let it sit for about 10 minutes and then tried it again. Got it started but not easily.
On the way home it had the same idle problem and it wouldn't really move. I at about 1/3 - 1/2 throttle it seemed to just stop. It would continue revving but nothing would happen. I had to have it in third gear just to barely hit 30mph (didn't try going faster than that).

Any idea what is going on? Last night there was no problems and now it is basically un-rideable.

EDIT: Not sure if related, but when I got it started, there was a bit of smoke from the exhaust (black'ish). Not much, but I can't recall it ever doing that before.
 

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You may have a vacuum leak. Spray some wd-40 at the vacuum hose and carb boots, see if the engine changes sound. Not into the air intake.
 

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Discussion Starter #3
You may have a vacuum leak. Spray some wd-40 at the vacuum hose and carb boots, see if the engine changes sound. Not into the air intake.


Nothing that I can see. And none of those have been touched.
Granted, half of it is hidden so far in that I have no way of seeing it without removing the carb. And that is not a job I am anywhere near qualified to handle.
 

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Discussion Starter #5
You can't "see"an air leak. And you do not need to remove the carbs to check for one.
Did the hose you replaced fall out? Did you cut the end going into the air box at a 45 degree angle?

Is your tank full? (POOGS) Bad fuel?

The hose is exactly where it was and is cut at 45 degrees.
The tank is completely full with fresh fuel, pumped today.
 

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EDIT: Not sure if related, but when I got it started, there was a bit of smoke from the exhaust (black'ish). Not much, but I can't recall it ever doing that before.
Black smoke means it's too rich, flooding.

An air leak will make the carbs lean, instead of rich.

You can check the petcock vacuum line to be sure it's dry. Otherwise, you'll need to find which cylinder is rich and check out that carb, checking the plugs is a good start.
 

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FREEBIRDS MC CENTRAL NY
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might be a dirty float needle.can try Wolfie's blowback method.it's a sticky in the fuel and carbs section

Sent from my LGL34C using Tapatalk
 

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Discussion Starter #8
Black smoke means it's too rich, flooding.

An air leak will make the carbs lean, instead of rich.

You can check the petcock vacuum line to be sure it's dry. Otherwise, you'll need to find which cylinder is rich and check out that carb, checking the plugs is a good start.
The bottom one is the vacuum, right? It appears to be dry. Took all 3 off and the left and right ones had a bit of fuel run out, but the bottom one was dry.

As for the flooding/smoke. Couldn't that just be from trying to start it for several minutes?
 

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The bottom one is the vacuum, right? It appears to be dry. Took all 3 off and the left and right ones had a bit of fuel run out, but the bottom one was dry.

As for the flooding/smoke. Couldn't that just be from trying to start it for several minutes?
Bottom, or center port is vacuum.

Smoke could be from extended cranking, especially if the choke was used any. When it's idling bad and bogging, check for smoke then as you try to rev it.
 

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Discussion Starter #10
As it is, it will barely run. To keep it going I need to constantly give it throttle. Will not idle on choke alone.
Seems like the smoke is just on startup.
 

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As it is, it will barely run. To keep it going I need to constantly give it throttle. Will not idle on choke alone.
Seems like the smoke is just on startup.
Can't say for sure, since I'm not there, but it reads exactly like flooding.

Adding choke to flooding will make it try to die. If it was lean, choke should help.
 

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Discussion Starter #12
So assuming flooding is the problem, what could the cause be?
I have changed nothing. Simply taken the tank off and put it back on.
 

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So assuming flooding is the problem, what could the cause be?
I have changed nothing. Simply taken the tank off and put it back on.
Could be a stuck float, especially if the tank was off long enough for the carb to dry out. Could look into the blowback method, or try light tapping on the carb bowls. Blowback is only temporary if the problem is dirt/debris, but if the float is just stuck, it can free it.
 

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If you took the tank off...you may have loosened up some crap that was in the tank. If it got down your fuel line, it might have clogged the pilot jet(s) ...
This would make it not idle. The same crap could also clog the choke (which is really just another fuel jet)
Seafoam, blow-back and rapping on the carbs might help, but you might need to remove the carbs to clean them properly if this is the problem....
 

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Discussion Starter #15
The tank was off for about 4-5 hours. It had around half a gallon of fuel in it if that matters.
It was moved around a bit, but no more violently than it is while riding. And correctly oriented the whole time.

Seafoam is not a viable option. It's not sold here and would take weeks to get.
 

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Doesn't matter really...you removing the tank may not have anything to do with your problem. Your symptoms however point to a clogged pilot jet....(If the bike runs fine at full throttle but won't idle)
Still recommend cleaning the carbs....if the other methods don't do anything....
 

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FREEBIRDS MC CENTRAL NY
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flooding will also cause it to not idle but run well at full throttle. it doesn't take much in the way of dirt to cause the needle in the float to stick open and flood the carbs

Sent from my LGL34C using Tapatalk
 
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Discussion Starter #18 (Edited)
Doesn't matter really...you removing the tank may not have anything to do with your problem. Your symptoms however point to a clogged pilot jet....(If the bike runs fine at full throttle but won't idle)
Still recommend cleaning the carbs....if the other methods don't do anything....
It doesn't run at full throttle. It runs very poorly at low throttle and as soon as it gets to about half throttle, nothing happens. It makes noise but it's like all power is just cut. To even get it home I had to keep it at about 1/3 throttle at all times.

EDIT: Now that I think about it, I might not have had it at full throttle. Is it possible for it to run like crap at low throttle, not at all at medium throttle and "well" at full?
 

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absolutely, because the pilot jet controls the fuel mixture until the engine pulls sufficient vacuum to raise the needle and expose the main jet. I was having this issue yesterday, and normally my bike is in tip-top shape and runs like a top, so it freaked me right out.

I rode through it, raising the idle to compensate and feathering the throttle until the bike would wake up, and it eventually loosened whatever was in there and let the carbs open back up. I tossed Seafoam in there, too, just to make sure my carbs got cleaned out a bit since I haven't been riding as often as I used to.

If you have no access to Seafoam, any kinda carb/fuel injector-cleaning gas additive will likely help as much as Seafoam, we just like Seafoam around here for some reason. The key with additive cleaners is to flow plenty of gas through the carbs, though, which usually means riding through it for a bit.
 

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Discussion Starter #20
absolutely, because the pilot jet controls the fuel mixture until the engine pulls sufficient vacuum to raise the needle and expose the main jet. I was having this issue yesterday, and normally my bike is in tip-top shape and runs like a top, so it freaked me right out.

I rode through it, raising the idle to compensate and feathering the throttle until the bike would wake up, and it eventually loosened whatever was in there and let the carbs open back up. I tossed Seafoam in there, too, just to make sure my carbs got cleaned out a bit since I haven't been riding as often as I used to.

If you have no access to Seafoam, any kinda carb/fuel injector-cleaning gas additive will likely help as much as Seafoam, we just like Seafoam around here for some reason. The key with additive cleaners is to flow plenty of gas through the carbs, though, which usually means riding through it for a bit.
If the weather permits, I'll try that tomorrow. If I can actually get it running long enough to get any revs.

It does have such a fuel additive in the current fuel. I'll try adding another dose. That along with the 99 octane should at least ensure that it can't complain about the fuel.
 
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