Well, she sure is resilient, even if she's a b***

[Incubus]

Suppose, y'all, for the sake of conjecture - which is all I am left with at this point - that at some point during this rebuild the tip of a pilot screw had broken off and gotten jammed in that little tiny hole in the carb barrel. Now further suppose that this needle tip was dislodged and removed, but that the hole might have gotten a wee bit enlarged. Not drilled-out enlarged, just distended a bit by the tip removal process. Would that prevent idling and cause flooding? Could it be remedied by screwing the air screw in just a little further?

I haven't messed with the air screws much as yet, beyond making sure they were not broken and setting them at the default adjustment. I figured that would be more of a fine-tuning thing, not a get-it-working thing.

Patrick

[Ken Talbot]

If it is the early style carbs with the sharp pointy needle, and if that needle did get stuck and break off, and if the broken piece got removed, there is no way on earth that the unmodified broken-off screw will ever work.

However, you can chuck the broken needle in a drillpress, use a good one for a shape guide, and apply a file lightly to the spinning needle to reshape it. The reshaped needle will work.

??

[DiverRay]

Patrick,
Just had a thought about a problem I had. Pull the float bowls, and VERIFY that the screws on the bottom of the idle jets are STILL ON. I had one come off on E.Liberty's bike when I did his carbs. Ran like junk,(PC statement) and was way rich on one cylinder. IF it was running well for a little while, that may be the problem.

[thewiz]

If what you're asking is ....

Would the hole in the venturi, if it had become enlarged when you used the push pin method to remove the broken off screw tip, cause the carb to malfunction? My guess is yes ... I have one #2 carb exactly that way and that is why I keep it in a pile of parts. I just don't trust it. Actually I never got the screw tip out, even with the deft hand of the great Promster, himself, prying on it .... abandoned the whole rack and bought another one. My thinking was that even when I did get it out (an ultrasonic soak would probably do it) that carb still would always be suspect because of the slightly larger hole. Is that about the way you're feeling? Someone probably has a body for a carb that isn't f**k'd up.

[Incubus]

Ken, it's not the needles that are bad. Those were either good or replaced. I am wondering if the hole the needle slides into could have been reamed out when a broken needle was forced out. I've read that drilling them out will mess up the idle, maybe forcing a broken tip back out could have also enlarged the hole.

Ray, it's only number one carb that gives me fits. The plug in the slow jet tower is there. I distinctly remember putting it back in yesterday.

The plug is definitely getting wet, so fuel is getting sucked in. It just isn't doing anything with it when it gets there.

Maybe I should just find another set of carbs and see if that fixes it.

Patrick

[thewiz]

Maybe I should just find another set of carbs and see if that fixes it.

Think you're onto something now ...

[Incubus]

Are the later carbs easier to work with than the early carbs like mine? I seem to remember that the air screw was sealed beneath a cap....

[thewiz]

the later carbs are ...

a different animal, Patrick. The idle mix screw did come plugged and in a different place on the carb body, but can be unplugged and most already are. The float bowl venting is different so there is not that double T fitting between 1&2 and 3&4 where the upper hose goes to the air box as on your carbs. The needle and seats are press in ... and to the best of my knowledge the circuitry is different as is the jetting as well ... everything geared toward lower emissions... is what comes to my mind. IMHO, probably not the 'best of all worlds' swap ...

[TopCatGr58]

Hey Patrick,

To answer your 1 plug good, 1 plug bad on the same coil....yes... there was an Xsive that had this actually on both of his coils.

Turned out that he wasn't getting the full 12 volts....or even 9 with those using the ballast resistor....and so the reduced voltage caused it to only generate enough power to push the spark thru the first plug wire and plug, but not enough to push it farther thru the engine and back up the other plug/wire!!!

So...you could first check the voltage for the suspect coil. Then If it's good, you could totally swap the coils, so the 2-3 coil would be connected to the 1-4 control/wires and vice versa, and put the 2-3 plugs onto the 1-4 and vice versa, and see IF the problem moves?? But if it stays with #1, then that will further confirm carb as the most likely problem.

GNEPIG posted a recent reply about the reamed out pilot hole messing up the usual 1 1/2 turns out setting down to 1/8 to 1/4 turns out!!!

Also, be sure your float doesn't slowly leak/sink? Keep at it!
T.C.

[Incubus]

A sinking float.... hmmmm......

That would actually explain a couple of things. Could it be that simple?

Guess I have to kill 16 minutes and pull the carbs again.

[Dragon Tamer]

Pat,
If I am reading between the lines properly I got that you have NOT tried adjusting the idle mixtures as of yet? Even a slightly enlarged hole should not keep you from being able to adjust the mixture. Remember that they do NOT have to completely shut off the fuel flow! I would screw that sucker down snug and see what happens. If it makes a difference (and it should) work from there.
A reminder though, if that works you may have to re-sync her to get the full benefit. When I give the Dragon her tune up I screw each mixture needle down until I hear a difference and then back it out slightly, then I sync the system. As I have stated before, the Dragon does not like to stay in sync so I have to do this about twice a year but have found that just syncing the carbs without setting the idle mixture does not give me as good a result as going through the proceedure completely.