**update**
Left cylinder still running VERY hot. Spark plug is running pure white
Right cylinder is running normally and left cylinder is now running hot. The tip of the spark plug came out completely white and the electrode is still black and sooty. Any ideas? Pics added
(http://tussey.dreamhosters.com/pictures/forums/gstwins/DSC00320.jpg)
(http://tussey.dreamhosters.com/pictures/forums/gstwins/DSC00321.jpg)
Good Spark (I think. I yanked the plugs out while it was running and set them against the cooling fins. Each spark plug had a tiny purple spark)
Good fuel (carbs cleaned, sync'd, good float height)
Good valves (all in specs, intakes a bit tight)
Oil level correct
Unsteady idle
Any ideas what it could be.
The bike worked perfectly before I let it sit for 10 days.
My rough guess: Did you leave the petcock in an on position?? You're obviously getting incomplete combustion/rich fuel mix. The carbs may have flooded and drained into the cylinder................... the spark sounds fine, mine is usually a bright blue but if you have enough spark that you can identify it in daylight, it should be fine.
Since your plugs are wet, it sounds like you have too much fuel.
Maybe your choke is stuck?
Do the symptoms change at all if you remove the air filter(s)? (Wondering if it/they got soaked somehow.... (http://bbburma.net/Smilies/dunno_black.gif))
Quote from: spcterry on January 05, 2008, 03:19:04 PMthe spark sounds fine, mine is usually a bright blue but if you have enough spark that you can identify it in daylight, it should be fine.
My guess is "electrical". When my bike ran kinda like yours, it was because of a corroded connection between the wiring harness and the signal generators. One of the things that confused me was that I got spark on both cylinders using [
my spark tester (http://bbburma.net/MiscFotos/100_0010_DIYSparkCheckTool.jpg)]. Granted, the spark was kinda yellow as I recall, but it still sent me in other directions because "I'm getting a spark, so that must not be it." :mad:
There are some fairly non-invasive tests you can do with a meter to see whether your problem is in the same area. I probably need to do a separate writeup for clarity, but hopefully these two posts (on the same page of an old thread) will get you started:
[
Post 1 - with diagram and narrative (http://gstwins.com/gsboard/index.php?topic=5500.msg44988#msg44988)]
[
Post 2 - with checklist of expected values (http://gstwins.com/gsboard/index.php?topic=5500.msg45007#msg45007)]
Quote from: mullethunter3 on January 05, 2008, 03:22:05 PMSince your plugs are wet, it sounds like you have too much fuel.
With today's prices, you can
never have too much fuel ... unless you actually have to pay for it. :icon_rolleyes:
Kerry, you kick ass!!!
Can you help me fix my retarded choke???? :laugh: :laugh: :laugh:
This is strange, my symptoms are changing. Yesterday I pulled the top off the valve cover and everything seemed normal. The bike fired right up and idled normally. Popped in a new set of plugs, took it for a ride and the bike works perfectly under 4k, anything over and it runs like crap. Struggles to reach 11k.
Pulled the plugs and the left one (left as sitting on the bike) is black and sooty and the right looks normal, if not a bit white.
Now I'm really confused.
I'm pretty sure it's not a carb issue. This bike ran perfectly for ~8 months and I didn't change a thing on it. Float height is correct, sync'd (althought I'm gonna double check this), choke isn't stuck.
Kerry I'm gonna run those test when I get my multimeter in the mail.
any ideas anyone else?
Quote from: tussey on January 06, 2008, 10:41:01 AMStruggles to reach 11k.
Don't they always? :laugh:
Quote from: tussey on January 06, 2008, 10:41:01 AMthe bike works perfectly under 4k, anything over and it runs like crap.
Interesting.
That doesn't sound altogether electrical, more like a clogged main jet or something. (http://bbburma.net/Smilies/headscratch.gif)
Quote from: tussey on January 06, 2008, 10:41:01 AMPulled the plugs and the left one (left as sitting on the bike) is black and sooty and the right looks normal, if not a bit white.
The white tip in your picture of the plugs is kinda odd. I'm used to seeing "black and sooty" plugs like the
Carbon Fouling entry in the [
Haynes Spark Plug Chart (http://bbburma.net/Scans/Haynes_SparkPlugChart.jpg)].
When I had my electrical problem (which only affected the right cylinder) the plug was indeed "black and sooty" and the (white) exhaust smelled like fuel because it wasn't all being burned. At one point I changed a connector and the bike acted like all was well ("Yay! I found it!") so I rode it about a mile and a half to a gas station. Just as I got there the problem returned. My bike did NOT run well at any RPM, so I got to push 'er home. :mad:
Quote from: tussey on January 06, 2008, 10:41:01 AMI'm pretty sure it's not a carb issue. This bike ran perfectly for ~8 months and I didn't change a thing on it.
Change or no change, it would only take a tiny bit of grit in a main jet to shut things down at high RPMs. But I'm not saying that's the problem, especially since the plug seems to indicate
unburned fuel, not a
lack of fuel.
Quote from: tussey on January 06, 2008, 10:41:01 AMKerry I'm gonna run those test when I get my multimeter in the mail.
Cool. If everything measures OK when the engine is cold, try again with the engine well-warmed up ... if possible.
Hey Kerry thanks for the response. I don't think it's an electrical issue. Most of the symptoms on my bike seem to have cleared up and things are looking much better.
Fixed
1. Rattling noise -- traced to exhaust pipe, only rattles when center stand is down
2. Soot on plugs -- this has stopped too. I think it was bad gas. Filled with new gas and now it starts reliably and doesn't misfire. Right plug normal, left plug see #5
Still Broken
3. CONSISTENTLY stumbles at 5k, runs fine above and below.
4. When stopping always hangs at 4k regardless of idle screw. When I adjust idle screw or blip throttle it then drops to ~1k idle and struggles to idle but never dies.
5. Left cylinder still running VERY hot. Spark plug is running pure white -- will clean/rebuild carbs
6. Oil leak from oil filter cover -- buying new gasket
7. Oil leak from left side oil pan (this started a few days ago, taking to bike mechanic to fix. I don't mess with the oil pan)
Okay.
Hello everyone.
I do not post much, because I am not proficient in riding and fixing my bike. I have received good help from reading posts, and will try to help out as best I can.
I am thinking that Kerry is right. There has to be something wrong with the carbs. I had to clean my carbs twice, because I didn't know about some of the tiniest of orfices I have ever seen.
I am sure that there is some foreign matter in the carb at this point because you can rev and it hangs. there is a problem.
Hope you find it.
laterz
ed
Have you pulled the right cover and checked to see if the ignition rotor and plate are secured and tight?
I thought I had carb problems once but the ignition pick-up plate had come loose.
Quote from: dgyver on January 07, 2008, 12:44:21 PM
Have you pulled the right cover and checked to see if the ignition rotor and plate are secured and tight?
I thought I had carb problems once but the ignition pick-up plate had come loose.
I pulled the cover the other day to crank the engine by hand. Didn't notice anything loose.
Quote from: dgyver on January 07, 2008, 12:44:21 PM
Have you pulled the right cover and checked to see if the ignition rotor and plate are secured and tight?
I thought I had carb problems once but the ignition pick-up plate had come loose.
Ditto on that second part. Plug wires are finicky things, with certain vibrations (rpm's) things get all screwy, then things are fine.
Just brainstorming...
Wouldn't this happen if the choke was stuck, or partially stuck? Lets say the choke was stuck but the owner didn't realize it and thought maybe the problem was simply an idle out of wack... then adjusted their IDLE to ideal RPM... ? Or maybe your carbs are out of whack or sticking on one side... ? Try SeaFoam? :dunno_white:
Cheers,
J
Maybe a hole in the choke diaphragm??? :dunno_white:
To get a true picture you need to judge the condition of the plug and gauge the mixture when it is running on the main jet at the revs where it is hesitant. Closing the throttle and killing the spark while at tickover will confuse the results.
Do a proper plug-chop as detailed below, check for airleaks around the inlet stub and check the diaphragms by holding them up to a bright light and looking for pinholes..... a compression test on the suspect cylinder wouldnt be a bad idea either although my money is on a partialy clogged jet or passageway in the carb. Use a bristle from a paintbrush to clean them out, never use wire, it scratches.
http://www.jpcycles.com/Tech/Articles/jettingpipes.aspx