surging, poor idle, fuel leaking from carb overflow tube

[Gorminrider]

Well, that's a possibly new one! Thanks for this report,prosnomonkey!

Yes, lubricate by all means but if the cable is connected to the surging issue that cable+housing is possibly really defective and in that case, you should replace it. It Could be a broken strand inside, catching the housing and that is dangerous....if a bunch of rust comes out when you are oiling it, turf it and replace.
a bit different issue, but Ive had this cable-routing issue myselfwhere turning the bars pulls on the throttle. I used pull-ties to hold it to the frame under the tank once I had it so moving the handlebars doesn't affect the throttle. It can be difficult to get it the routing just right and when I use the adjustment at the handlebars to (temporarily!) adjust the idle, the "turning acceleration" can show up again on one bike even now.... Oh, usually, it wouldn't cause surging unless it's in the parking lot making sharp slow turns but that's not so safe either...

I wonder if Possibly somebody has put taller handlebars on without lengthening the cable ...?

[prosnomonkey]

Yes there are taller handlebars but there seems to be plenty of slack in the cable. I was able to loosen the cable so that there a little slack in it when it's completely at idle. I have to turn the throttle grip about 1/4 - 1/2 inch before the slack is taken up. At idle, the handlebars can move the whole range without moving the throttle cable. However, if I put some tension on it, say at 1/2 throttle, the cable gets tighter and opens the carbs up when I flick the housing with my finger. It doesn't seem to release though. I'm going to get some oil on it tonite and see what happens

[Gorminrider]

yes, a bit of slack at idle at the twist is a good thing for most of us.

Maybe a squashed cable housing might be pinching the cable too...? Wiggling or pulling on the housing at half throttle will of course tweak your throttle if the ends are lifting out of their "cups" at the carb and twist grip. Therefore, the housing should be held to the frame so that these ends stay happy and relaxed in their cups.

[prosnomonkey]

You have got to be kidding me!!! I lubed up the throttle cable and by golly the surging has pretty much gone away! I took the bike for a test run that turned into an hour and a half ride and it only surged once or twice and very little at that. What an enjoyable ride it turned out to be. I did notice that as the gas tank got emptier, the surging came back a little more, but nowhere near as bad as before. I can't believe I rode long enough to go through most of a tank of gas!

So it seems the throttle cable was a major part of the problem, and I will probably end up replacing it in the near future, though it seems to be ok for now. Although I wonder about the occasional surging that I experienced...? Could it still be the throttle cable or is there another ghost wandering about? There was no pattern to it except I noticed it more when the tank was maybe 1/4 full. At this point I was near home again and although I should have gassed up again and kept going, I didn't. Oh well, looks like I have to go for another ride tomorrow for more "testing"

I can't express enough my gratitude to all of you for your help! THANK YOU THANK YOU THANK YOU!!!

[Gorminrider]

hi,prosnomonkey! more good news,eh! perhaps the surging is a bit of stickiness at the carb float needle too...less fuel in tank, less pressure on the needle- or maybe the strainer in the tank is a bit choked.

But keep on it -You don't want surging.

[prosnomonkey]

The float needles didn't stick at all (I checked when I had them off) but I did notice one was not as responsive (springy??) as the other, so this maybe something to look at... as much as I do not want to take the carbs apart AGAIN. As for the strainer in the tank, I took the petcock off and there was just a hole in the bottom of the tank, didn't seem to be anything inside that would strain/filter anything. The screens on the petcock seemed ok but it might be worth taking it off and having another look. I did notice that when I put the petcock at PRIme and waited, that gas began leaking out of the swtich/lever area after 15 seconds or so, not sure if this is normal but makes sense as the carbs get filled, the gas has to go somewhere. Petcock seemed to flow well when I had the tank off and set it to PRIme and drained the tank, but did not flow at all when on REServe or ON

[Gorminrider]

No, it shouldn't leak around the tap with PRI on.and it doesn't make sense. for a Motorcycle to drip gas at any time.s

......since the vacuum-activated Run and Res(reserve) is apparently functioning,is there any dripping while you are riding? ie:Imagine the headlines-"Motorcycle Explodes and Burns at Stoplight"

fingers crossed, but Occassionally, just turning the tap a few times stops the leaking on a tap that hasn't been moved much in its life.

[prosnomonkey]

no it doesn't leak at any other time ... I wouldn't be riding it otherwise. Also it doesn't always leak on PRI. Yesterday I moved the tap to PRI to start the bike and no leak, so I'll keep an eye on that. Rode the bike to the gas station and filled her up, did some errands around town and there was no surging, did not use much of the tank of gas tho

Edit: I just checked prices on the float needle and bike bandit has it at $48 while Boulevard has it at $40. Buying two on a "maybe this is the problem" seems like a pretty steep price. Is there any way I might test this theory before sending another $100 down the fuel line? As stated in above post, neither one "sticks" as Gorminrider suggested and the springs inside seemed not very springy... are they supposed to be quite springy or a little soft?

[Nessism]

Places like Z1 Enterprises sell float needles separate.

[prosnomonkey]

I took it for a short ride today, about 50 miles started with a full tank. It surged a little bit at the beginning, but did not seem to do so any other time in the ride. I haven't tuned the carbs except for a bench tune and making sure the adjustment needles at 2.5 turns out as well as setting the float height correctly. Going to attempt to sync the carbs as shown elsewhere on the forum tommorw and see if I notice a difference in performance.

Again thanks for all the help! Nessism, thanks for the heads up about Z1. They sell the float needles in a six pack for $25. I wonder if anybody needs 4 of them?

[prosnomonkey]

Did some riding and data collection today, this is what I found:
All the previous riding I have done was with the Fuel Adjusment screws at 2 1/2 turns out
When I turned the screws to 3 turns out, the surging got worse as in it happened more often and the surge was more dramatic
When I turned the screws back in to only 2 turns out, the surging almost went away.
Do I need turn the screws further in to eliminate the surging say to 1 1/2 turns out? Will the engine run too lean? Anybody know what might be going on here?

Secondly, When I got home just out of curiosity, I put the bike on the center stand, and while the engine was running, I pulled the spark-plug caps off. When I pulled the right hand spark plug cap, the bike died almost immediatly. I replaced it, restarted the bike and pulled the left hand spark plug cap, but this time the bike just kept running albeit at a lower idle. (Right/Left as one sits on the bike)

Is this normal? I assume not, as I had read somewhere else here that this is another way to sync the carbs

Thanks again for your time

[Gorminrider]

I don't know what's going on- I can only guess.... surging and idle-mix are two different issues, to me, anyways, and I worry when it seems fiddling with one issue fixes the other...

The more the throttle is opened ,the less important the idle-mixture is.

However, it may be a clue that turning the idlemix screws IN is reducing fuel at the manifold....

per idle mix,
here's a place to look:

http://members.dslextreme.com/users/bikecliff/images/highest_rpm_plug_chop.html

here's a pdf:

http://members.dslextreme.com/users/storagecliff1/images/Adjusting_Idle_Mixture_on_CV_Carbs.pdf

as to "...as I had read somewhere else here that this is another way to sync the carbs" yes,it has been suggested as a way to synch two-cylinder bikes,because they are much simpler than the fours but synching is done at the throttle plate opening and not the idle mixture. Idle mixture and valves and plugs etc is done First. Synching is the final act...

[Gorminrider]

...I forgot to include this guess...perhaps the vacuum slides are sticking...

AND...it may be that the "surge" is when your bike is finally operating properly. You would feel a surge when the cylinder that wasn't working suddenly does.

[prosnomonkey]

I checked the slides when I did the bench sync by moving them up and down with my fingers and they seemed to be operating ok... smooth up and down movement with no hesitation. Is there another test I should do? I am going to go ahead and replace the float needles and the throttle cable to make sure this is not the issue
Jeremy

[Gorminrider]

good, good... it took me awhile to realize one of mine was sticking so I had to mention it. again.That new throttle cable is a little money well spent by the sound of it. ...new floatneedles is great but of course they seal to "seats". I've not yet had a problem with these myself, beyond cleaning 'em and checking for corrosion .

and I guess you've been over the wiring to be sure there's no possibility a wire to the coil or ignition is intermittently grounding or open circuiting.