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

[Incubus]

Hi y'all, it's time for my semi-annual make Succubus idle pursuit. In this corner, is Succubus, the 1979 XS1100F - the reigning champion. In the other corner is Patrick, the frustrated suitor. I've kind of left Succubus alone since fall. It was better for both of us that way.

How much does this b**** taunt me? I left her sitting in the garage watching as I restored a 1969 Honda CB750. Then I rebuilt a 1987 Honda Shadow VT1100. Both run great (and idle). Succubus sat since probably September. This week, after months of her gathering dust, I put a charge on the battery, touched the starter button and she roared immediately to life. But idle? Yeah right. maybe in another space-time continuum.

I now have seven vintage bikes. I've rebuilt them all from lawn art to self-ambulatory machines. Six of them run and idle beautifully. I don't know why I can get Hondas, Suzukis, Kaws and even other Yamahas to idle, but not this bike.

So it's back to it. The Meeting os the Minds is coming up and Succubus is going to bring me there, even if I have to tether her in the bed of the truck and ride the cargo with my wife pilots the diesel.

I'm pretty sure I've got a vacuum issue since number one cylinder doesn't like to fire consistently unless I'm cranking into a wheelie. This is my game plan. Please offer suggestions of anything else I can try.

I plan to pull the carbs and carb holders and put a Ford gasket under carb holder number one, ala John. I plan to replace (again) all the rubber caps on the vacuum ports and the vacuum line that runs from carb number to to that thing under the left side cover whose name escapes me. While I have the carbs off I plan to clean the pilot circuits yet again and check the new (last summer) slow jet on number one for blockage.

What else can I check?

A few clues:
1. The carbs have been cleaned about 600 times. The carb holders are new and have no cracks at all.
2. when I switch the plug wires from one and four, the problem stays with cylinder one. so I don't think I have a spark issue.
3. When I have the bike on full choke it idles at about four grand or more. The idle drops immediately when I let off the choke.
3. The bike idles, but only above about 3000. At that idle all four cylinders pop. bewlo 2000 rpm the engine tails off and dies.
4. On the road, the bike runs exceptionally well as long as I keep the idle up. if the engine speed falls the engine falters.

I have to go change into a wifebeater tee shirt. Maybe intimidation will help.

In the meantime, how's about a suggestion or two....

Patrick

[wingnut]

Sounds like pilot jet problems to me. I take it they are clean but are they the right ones? Think there is a thread on the number of holes in the sides and if they are from a kit they are not worth a damn. I would get 4 new OEM pilots and start from there. I used 4 from the first set of kits I bought and the bike ran but very badly at low rpm. installed the OEMs and purred like a kitten.

[79XS11F]

My 79 xs1100 idles nice at 900 RPM and this is I did it...
I REPLACED the coils (NOS parts) and installed new plugs that have were gapped to spec.
I put in a NOS Stock air filter and make sure all air passages including those in the air box were completely clean.
I confirmed that the the carbs were not just clean, but that they function properly.
I REPLACED the fuel petcocks (NOS PARTS).
I Installed fuel filters on the fuel lines.
I rebuilt all timing components and REPLACED the pick-up coils again using NOS parts.
I took the bike for a run to bring her up to FULL operation temperature before syncing the carbs using 4 gauges.
I color tuned the pilots and set the idle to the factory spec.
All that tune up work was done after I completely cleaned and rebuilt the head and cleaned the carbon off the tops of the pistons.
Keep at it and you'll win her over.

Rob

[Incubus]

Succubus doesn't get any more stuff until she starts putting out....

[HobbyMan]

I have found that this technique doesn't work too well. You just gotta keep throwing money at here untill you get results. Hmm... That works on several levels Anyway... How compression on the #1?

[skids]

When they reach a certain age they seem less interested in putting out and they still expect "stuff."

Originally posted by Succubus
Succubus doesn't get any more stuff until she starts putting out....

[Incubus]

The compression seems good, HobbyMan, although I haven't put a gauge to it this time around. I vaguely remember it being good. I put a Ford thermostat gasket (as per John) between the number one carb holder and the head. I turned the engine with the starter and held my hand over the end of the carb holder. The vacuum was strong enough that the starter could not pull past it with a full charge on the battery.

I've got the carbs off today, resetting the float heights, cleaning the needle valves and doing a visual inspection of the jets. I sprayed carb cleaner through number one, but tonight I'll probably tear is down completely and just hose everything out.

I checked the airbox for obstructions and found none and I cleaned the K&N stock air filter. I also found a hose clamp on one of my Hondas that is a little smaller than the stock carb clamp. If I can get it on it will make sure there are no leaks from the carb.

Succubus has sat long enough that everything looks just a little unfamiliar, so I get to figure it out all over again. This is kind of what I wanted. Still, I had the carbs pulled within 20 minutes.

No bike has beaten me yet.

Patrick

[ross]

xs11's and wifebeaters.....

hey there Succubus....hear ya about thowing money at the problem.....the "rebel devil" restoration fund is way dry....but with a little $$ ($15 or so) you can come up with some very cool tools that will help you unlock the mystery of the XS11....vacuum gauge and a laser thermometer.....to sync and double check pipe temps.....with it, i got the pipes burning with about 10 degrees between all 4 pipes....took her out and she ran like a dream....i haven't checked the plugs yet, but i know she is really close...mind you my pipe temps before i started were over 100 degrees different......AND it doesn't require removing the carbs.....all i know is she ran pretty good before i started, but got her out on the highway today and wound her out.....100 mph at 6k rpm....and lots of throttle left to go.....took her up to about 110 and then the "pucker factor" kicked in and had to back her down....good thing i did...michigan state trooper 1/4 mile ahead on the cross over....luckly he was running laser on the oncoming lanes....of course it would of been funny as h*ll to have him pull me over and ask me just how fast i was going....to which i would of replied, "XSively fast officer!" (as he runs the number of my original 1979 michigan cycle plate).......let me know as i'm still messing with mine, but i can feel her getting faster and running better the more i fine tune it.....let me know if i can help....btw, this is my first carb rebuild and i have learned much wisdom from my mistakes and members of the family....ross

[81xsproject]

Patrick, you have mentioned cleaning, but are you using compressed air to blow through all the passages. If so, are you using your fingers to force the air through the various pilot passages? What I do after spraying plenty of cleaner in from all sides (pilot tower, idle mixture hole, and pilot air jet) is put the into the pilot AIR jet hole and give it a few good shots paying attention to all the places spray SHOULD come shooting out (pilot tower, 3 holes in the throat, and sometimes you can see some come out the mixture screw hole). Then I respray and try to isolate the individual passages respraying cleaner after ever session of air. This can amount to being a bit of a finger contortionist. While blasting the air from the pilot air jet, I block BOTH ends of the main jet tower, install and lightly seat the mixture screws and with the same. This doesn't totally isolate, but it helps. The spray should come mostly out of the pilot jet tower and some from the 3 holes in the throat. Then I install the pilot cap screws and do the same thing. Then I remove the idle mixture screw, spray down in there, block the 3 holes in the throat with my finger and force compressed air from the top of the idle mixture tower.

Do each passage from one carb to the next the same way. This will give you a comparison. My best example of this was on a set of bowls. I noticed that on bowl REALLY seemed to shoot out the carb spray. I thought the others might all be clogged. Turns out that one was missing the starter jet.

Doing it this way, you will notice if for instance one carb never shoots spray out of the 3 holes or something. Hope this helps. PS compressed air is king of clean carbs.

[planedick]

Again...

I have to mention that a PROPER synch is probably THE MOST IMPORTANT part of the carb restoration process. A bad or not idle is the first indication of out of synch carbs.....

[Incubus]

Maybe I can live with a 2500 rpm....

Because my XS11F idles at that speed and runs like a bat outta hell. I can shift through all the gears, find first without grinding, find neutral easily.

But I don't want to. Here's where I stand now....

I do not believe I have a problem with vacuum, at least anymore. Nos. two through four cylinders run great and no 1 kicks in at about 2500 rpm. The number one plug is wet when it doesn't fire, and when I pull the no. 1 plug and ground it to a head nut I get a powerful looking blue spark.

So now I'm going to look at timing before I synch it again. I get some minor backfiring on acceleration. Two questions:

1. I forget - where do I hook up an external dwell/tach? Obviously I don't need to check dwell, but I have no points to attach to to check engine speed. I do not trust my onboard tach for these tests.

2. I remember that my timing bar is a little bent, but I don't remember which way. Should the cam timing mark line up at TDC on Nos 1 and 4? I'd rather not pull the valve cover to check, since I will almost certainly destroy the gasket. That's just the way my luck rolls. I have a dial gauge, though

I remember now why V-twins are allowed bigger displacement when they compete against fours. This bike has noticeably more high end torque than my VT1100 Shadow.

Reliability is close. I can feel it....

Patrick

[TopCatGr58]

Hey Patrick,

You've cleaned the carbs enumerable times, perhaps you've cleaned them too much and possibly damaged the throttle plate/butterfly shaft seals?? Have you checked that lately for possible vacuum leak? I know it might be kinda hard to tell if you have a change in engine speed with it already running at 2500 when trying to find a vacuum leak!

Wet plug sounds more like flooding, vs. not being able to draw the fuel at low rpms due to vacuum leak or clogged pilot circuit??

As for the tach connection, you'll want to use the negative terminal on one of the ignition coils, not the PUC's!

The "T" on the timing plate is what lines up with the indicator when at TDC for #1, not the "C" mark! The "C" mark is for adjusting the cam chain tension.
T.C.

[thewiz]

I, for one ....

am glad to see you back posting again. Frankly, Patrick, your posts are some of the most well written, entertaining and certainly challenging found here on this site. Keep posting, you are one very funny man !! Once you get this thing fixed, I hope you still continue to post about something

Not meaning to make light of your efforts, but have you swapped the plug outa' #1 into another hole? Also, how about finding a local MC shop with an ultrasonic cleaning tank?? ... I have found that they are usually more than willing to soak 'em for a small fee ... and the results are incomparable ...

[Incubus]

Cleaned the carbs too much?!?

That is a frightening concept, TC, and one that I thought I would never read on a vintage bike forum. If, however, you are interested in the type of material that can be found several layers below the veneer that our carbs came from the factory with, just ask. I cleaned off so many layers that the American Paleontology Institute has been calling asking if I found any old bones or teeth.

The answer is no - no dinosaurs - but at one point I did think I stumbled upon some valuable mineral deposits.

I have not, however, immersed the carbs in anything. Just B-12 and compressed air. The slow jet passages are so clean now that when I shine a light on them the glare is visible from outer space.

I delayed the timing thing yesterday and instead I synched the carbs. The engine revs so smoothly now that it sounds like a purr. I even got the idle down to about 1500. It's amazing how smoothly this old bike will idle on three cylinders. It is driving me bat**** crazy.

I rode Succubus around yesterday for an hour or so, my Vetter Cyclesound blasting out the entire LA Woman CD by The Doors twice. Young women along the route were rushing into their houses to quickly reappear in very small bikinis so they could dance to my tunes, so seductive is an old guy on an old bike listening to old music. It was cool.

And this bike flat kicks ass when I keep the revs up. Anything over 3000 rpm and she's a purring chick magnet.

Unless the seal on the butterfly is leaking, then I have eliminated vacuum leak as a cause of the problem. Tonight I go back to the spark side. Can anyone suggest any spot in the electrical system that could discourage spark on just one cylinder? The plug wire has been clipped, the plug cap is new (and the second new cap I've tried), and lately I've been recirculating the plugs from number one to the other three cylinders so they can be cleaned by actual fire.

Patrick

[DiverRay]

Patrick,
If #1 is WET at idle (or the attempt to idle) , Then you need to look at the carb one more time. I would start with the floats, and then the jet and screw for the low speed mixture.
ALL FLOATS ARE AT 26mm????
NO BROKEN NEEDLE ON THE ADJUSTMENT SCREW????
ALL FOUR JETS ARE THE SAME????
If the answers to these questions are all yes, then look once more at the float, and VERIFY that they are parallel, and move ONLY up and down. IF there is too much "side to side", they can bind on the carb body, and flood.