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Discussion Starter · #1 ·
The last time I rode my gl500 was before I deployed in late 2009. I had finished customizing it earlier in the year after over two years of building. Since I got home in late 2010 I've been building my business back up and adding little ones to our family. Today I finally sat down and worked on getting my bike back up and running.
I flushed the carbs, connected a new battery, filled it up with new gas, and it started right up. The one problem was that when I went to ride it around the block for the first time in 5 years, it stalls out in 1st gear just trying to make it up my driveway! It idles fine, but has absolutely no power. Does anyone have a guess or suggestion? It's been sitting for a while, but I changed my fluids first thing. Any help would be appreciated. My first thought was something to do with compression?
 

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I'm wondering about your fuel flow from the tank.

Maybe you have enoughto sustain idle but not enough for any throttle opening.

Open the carb drains and see if you get steady flows.
 

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Discussion Starter · #5 ·
Gotcha. I hope that's it since it would be an easy fix! I'll try to check it in the morning before I head out and let you know. Thanks.
 

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If you put it in neutral with the clutch engaged, does it still act the same?

From my own BTDT with similar problems on bikes that have sat for a while, it's usually fuel/air related.

Fuel delivery first: Check for Clogged filter

Pinched/obstructed Fuel Line
Plugged tank vent (try running with gas cap off)
To check all at once, run an auxilary fuel supply directly to the carbs and see what happens.

Dirt/rust from sitting can cause a restriction in the main jets also
Air:
A rats nest or ????? blocking the air box intake
Hardened intake rubbers leaking at clamps or cracked

A pinched or leaking vacuum hose to the petcock


 

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Discussion Starter · #7 ·
Neutral with or without clutch engaged runs and revs seemingly normal.
I've customized heavily, so I have individual uni-filters on the jetted carbs. I'll try running with the gas cap off, and bypass my in line fuel filter just for a test and see what happens.
 

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Under load, I would look at how clean the carbs really are, especially after sitting that long. Varnished gas is a bitch. And with a modded system, the variables are expanded. It may just need to be run like a bat outta hell on a clear stretch for an hour or so with some Seafoam, but I'd give the whole fuel system a good clean either way.
Fuel/Air/Fire

Joel in the Couve
 

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Discussion Starter · #9 ·
OK, I finally got to pull the carbs off today after work. I stripped them and cleaned them out. One of them wasn't flowing when I opened the drains to check them. I put the carbs back together and put them on the bike. I checked the fuel lines and my inline filters and they all flowed well. Now when I open the fuel valve from the tank fuel pours out of the carb drains via the overflow (yes I made sure they were closed) and it definitely won't try to start. Fuel is soaking my plugs as well when trying to start the bike. One odd thing was that I can't find where the small vacuum line on one of the carbs connects to? Maybe that's the problem? Also now my starter switch isn't functioning and to get it to turn over I have to jump the solenoid! UGH!
 

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When one drain wasn't flowing, it sounds like the inlet valve in that carb was stuck shut.

When both carbs overflow, it sounds like both inlet valves refuse to shut. I don't know how familiar you are with carb cleaning, but is it possible the valves or the float aren't installed properly?

As for the starter switch not working - instead of jumping the solenoid (I presume you mean bridging the high current side), I prefer to use small clip leads to:

(1) ground one side of the solenoid coil. This bypasses the cutch safety switch and the neutral switch. If either of those is the problem, this test will point the way even as it lets you crank to work on the other issue. Be sure you're in neutral and/or have the clutch pulled in.

(2) other side of the solenoid coil to the battery +12V. This bypasses the starter switch, ignition switch and fuses. As in point (1) it lets you crank while it points the way to the problem.

The vacuum hose you mention may just be a vent. Can you get a clear picture if it? Or describe the port it attaches to?
 

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Discussion Starter · #11 ·
When one drain wasn't flowing, it sounds like the inlet valve in that carb was stuck shut.

When both carbs overflow, it sounds like both inlet valves refuse to shut. I don't know how familiar you are with carb cleaning, but is it possible the valves or the float aren't installed properly?

As for the starter switch not working - instead of jumping the solenoid (I presume you mean bridging the high current side), I prefer to use small clip leads to:

(1) ground one side of the solenoid coil. This bypasses the cutch safety switch and the neutral switch. If either of those is the problem, this test will point the way even as it lets you crank to work on the other issue. Be sure you're in neutral and/or have the clutch pulled in.

(2) other side of the solenoid coil to the battery +12V. This bypasses the starter switch, ignition switch and fuses. As in point (1) it lets you crank while it points the way to the problem.

I actually didn't remove the floats when I cleaned out the carbs. I just unscrewed the covers and sprayed them down with carb cleaner. I'm with you on it being a problem with the fuel not being shut off inside when it gets full, but I have no idea what I did wrong in putting them back together.
 

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. . . when I cleaned out the carbs. I just unscrewed the covers and sprayed them down with carb cleaner. . .
Ah. You didn't even blow out the main jet and emulsion tube? You should probably give the carbs a really thorough cleaning - spraying out each and every passage as a minimum. A number of users here rave about the results of ultrasonic carb cleaning as well. Search the forum archives and the wiki for more details than a person and assimilate.

When you open the carbs back up (a drag to do over, but it will be faster the second time), inspect the float. Maybe the hinge pin came loose on one side. When I put carbs back together, I sometimes blow in the inlet nipple while moving the float up and down, just to verify the inlet valve action. This will lead you straight to the problem.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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If your key switch is malfunctioning, it could be preventing spark, just like having the kill switch in the off position. Do you get main power with the switch turned on? If not, clean the contacts in the big block connector, and try again.


R
 

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Discussion Starter · #14 ·
If your key switch is malfunctioning, it could be preventing spark, just like having the kill switch in the off position. Do you get main power with the switch turned on? If not, clean the contacts in the big block connector, and try again.


R
I have power to the lights. I don't have a key switch anymore, just a hidden toggle to turn off power. I'll try cleaning the contacts and see if that helps.
 

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I have power to the lights. I don't have a key switch anymore, just a hidden toggle to turn off power. I'll try cleaning the contacts and see if that helps.
Then check continuity through the kill switch, if you still have it. With the plugs wet, it sounds to me like a spark failure. Verify the connection of the black/white wire under the seat (you'll need to access it to check continuity, anyway).

Another possibility is that it's just flooding, given the failing float valves. Will it fire after spraying starting fluid or carb cleaner into the dry carbs?


R
 

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With the plugs wet, it sounds to me like a spark failure . . . Another possibility is that it's just flooding, given the failing float valves. Will it fire after spraying starting fluid or carb cleaner into the dry carbs?
R
With fuel pouring out the overflow ports, I suspect flooding is more than a mere possibility.

Still, it is a good idea to check the spark. It's easy to do.

Use common sense with that open spark in the vicinity of spilled fuel.
 

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Discussion Starter · #17 ·
Ok guys, thanks for the advice. I got the floats unstuck after tearing them down and cleaning the carbs better and it stopped the overflow problem. the bike started up just fine and then I noticed some fuel leaking from where the fuel line goes into the carbs (I think I damaged the hose when pulling it off so many times), so I put a new section of fuel line in and as I was attempting to place it over the nipple on the carb, I broke the nipple off! Any idea if I can replace this part, or am I screwed and left with buying new carbs? Here's a pic
 
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