&*%##@! carbs

[Rasputin]

What about your starter plunger seals? I have seen that throw people a curve ball because, pretty much, no one pays any attention to them when rebuilding carbs.
If you push the slides up and then cover the kidney shaped hole with the enricher/choke off they may drop slowly or not at all. If you open the choke they will not stay up at all, they drop instantly.
So I am wondering if you may have a small leak which may be allowing extra fuel in once warmed up. Things like the slides not staying up, or fuel being drawn in thru the enricher circuit etc.
Just some thoughts for you to ponder.

[motoman]

I was thinking along those lines too but I checked the pick up coils and they OHM out at 730 - 750 on the 2000 setting. That's about right. And, I checked all the connections. Put new resistor caps on and trimmed the wires.

I'm thinking it's carbs because 1-3-4 plugs are sooty black, #3 is a bit rich but the electrode is tan. Not consistent with an electrical problem.

Hmmm........may wanna unhook the coils and check the ohms across the two poles, when coils are cold, and again after they have been hot from riding.

[BA80]

I've decided to put another set of carbs on and either confirm or eliminate a carb issue.

Process of elimination I guess.

I'll take them to work with me in the AM and get them set up so I can get them on there after work sometime when I'm feeling froggy.

[BA80]

Greg,
I supposed to be the stupid new guy here but my Dead Duck was running like poop after warm up at low RPM and the idle was all over the place. We found the battery was bad (thanks Mike). With a good battery it runs fine.

KURT

Never answered that one Kurt. It has a new AGM battery in it.

[kboehringer]

fuel/air mixture is TOO rich.

Maybe because it's not able to properly burn the fuel mixture that it's given, which may be correct, not because it's getting too much fuel. We will all find out tomorrow when Greg tries the bike with different carbs.....

Good luck tomorrow Greg! ....Hope it works and eliminates the other numerous possibilities! That new battery eliminates one of them.....

Sincerely,

[BA80]

Ha ha ha.......I feel like a Hardley rider, I gotta keep revving it at stoplights to clear it out and it sounds like crap when I take off.

[motoman]

Ha ha ha.......I feel like a Hardley rider, I gotta keep revving it at stoplights to clear it out and it sounds like crap when I take off.

....all ya' need is the right 'vibes' to go with.

[bikerphil]

The jets are some I had that were removed from parts carbs and inspected quite well for damage and to make sure they had the square in a square genuine Mikuni markings

Is it possible the pilot jets could be the VM type instead of the BS type? That would cause rich low speed condition, the spray angle is totally wrong. The two look identical except for the spray end.

[BA80]

Kinda what it acts like but I'm certain they are the 6 hole BS type. I don't even keep the others if I find 'em in any.

[TopCatGr58]

Hey Greg,

I was going to suggest the enrichener plunger leak until I saw Rasputin's post.

A NEW battery doesn't rule out weak low rpm coil energy. Is this problem on your 80SG machine, you didn't specify? As Brant has stated before, low spark power at low rpms can mimic carb problems. Remember the alt doesn't put out much above 12 volts until around 2000 rpms, and your bike if still OEM is running the power thru the BR, so your coils can be getting even less power at idle/low rpm range, which could cause all of the plugs to be sooted. One was not terribly sooted, but remember there's a primary plug where the power comes out of the coil...thru that 1st plug which would get the lion's share of voltage, and then thru the engine and then back up thru the other plug...but if the volts are very low....may be just enough to almost adequately fire the first plug, but not enough left over to properly fire the second paired plug.

This is that rare scenario where both 1-2 plugs or 3-4 plugs that would normally be linked by fuel problems, could actually be ignition problem due to very low voltage only adequately firing the first/primary plug in the coil pair...and if they are both on the same side ie. 1-2 or 3-4, then you can have that type of pairing of fouled/sooty plugs which would normally be fuel problem related, but in actuality be an ignition/low voltage problem. JAT.

T.C.

[XJOK2PLAY]

Greg,
The hard starting problem after hot you describe sounds like LOTS of XS11's to me.

Bohn's bike has done that forever. Takes forever to start. Has to open the throttle wide open when cranking, and finally starts like it's flooded.
Yet, his bike has been tuned as well as you can get one tuned, gets 40 mpg, but continues to do that.

My Maxim used to do the same thing, until I put the Dynajet kit in, and finally hit paydirt when I got the needle steps on their leanest settings. That stopped the problem, after I got them synched well. That solved a MULTITUDE of problems.

I've always thought it's a combined problem the 11's carbs have.
Engine warms up, you shut it off, put it on the sidestand, gas percolates in the bowls, causing a flooding vapor situation, the more the starter cranks, the lower the voltage goes to the coils and ignition...
'Cause when they finally start, they seem to be flooded.

But... I do understand your frustration... IIRC, it didn't use to do that, right?

All I can tell ya is it seems to be a common problem.
I just posted to a guy on COG that's describing the same problem he has with a '93 Virago...

[BA80]

Hey Greg,

I was going to suggest the enrichener plunger leak until I saw Rasputin's post.

A NEW battery doesn't rule out weak low rpm coil energy. Is this problem on your 80SG machine, you didn't specify? As Brant has stated before, low spark power at low rpms can mimic carb problems. Remember the alt doesn't put out much above 12 volts until around 2000 rpms, and your bike if still OEM is running the power thru the BR, so your coils can be getting even less power at idle/low rpm range, which could cause all of the plugs to be sooted. One was not terribly sooted, but remember there's a primary plug where the power comes out of the coil...thru that 1st plug which would get the lion's share of voltage, and then thru the engine and then back up thru the other plug...but if the volts are very low....may be just enough to almost adequately fire the first plug, but not enough left over to properly fire the second paired plug.

This is that rare scenario where both 1-2 plugs or 3-4 plugs that would normally be linked by fuel problems, could actually be ignition problem due to very low voltage only adequately firing the first/primary plug in the coil pair...and if they are both on the same side ie. 1-2 or 3-4, then you can have that type of pairing of fouled/sooty plugs which would normally be fuel problem related, but in actuality be an ignition/low voltage problem. JAT.

T.C.

I'll be changing out the carbs first to either confirm or eliminate a carb issue. Thanks TC

To answer your other questions, this is an SG (not Okie) all stock except Harley mufflers and a drilled airbox.

Greg,
The hard starting problem after hot you describe sounds like LOTS of XS11's to me.

Bohn's bike has done that forever. Takes forever to start. Has to open the throttle wide open when cranking, and finally starts like it's flooded.
Yet, his bike has been tuned as well as you can get one tuned, gets 40 mpg, but continues to do that.

My Maxim used to do the same thing, until I put the Dynajet kit in, and finally hit paydirt when I got the needle steps on their leanest settings. That stopped the problem, after I got them synched well. That solved a MULTITUDE of problems.

I've always thought it's a combined problem the 11's carbs have.
Engine warms up, you shut it off, put it on the sidestand, gas percolates in the bowls, causing a flooding vapor situation, the more the starter cranks, the lower the voltage goes to the coils and ignition...
'Cause when they finally start, they seem to be flooded.

But... I do understand your frustration... IIRC, it didn't use to do that, right?

All I can tell ya is it seems to be a common problem.
I just posted to a guy on COG that's describing the same problem he has with a '93 Virago...

This isn't Okie Bob, it's the other SG. It starts great, it's an idle issue when the engine get up to temp, seems to get worse if I'm in traffic. Embarrassing.

[motoman]

just inform us here if the earlier carb bank eliminated the issue being carbs.

[BA80]

Got a set all put together with stock size mains and pilots. I'll try and screw up the ambition to install them tonight.

I'm gonna have to swap out the top half of the airbox or drill the nipples on the existing one too for the bowl vent hoses.

[TopCatGr58]

Got a set all put together with stock size mains and pilots. I'll try and screw up the ambition to install them tonight.

I'm gonna have to swap out the top half of the airbox or drill the nipples on the existing one too for the bowl vent hoses.

Hey Greg,

Why go thru all that bother for just a test setup?? Just put some fuel filters on the ends of the vent hoses and leave them hanging in the wind or zip tie them under the tank??

T.C.