carb/fuel problems?

[joejoe]

I have an 80 1100 special that I picked up from a friend who let it sit for 3 years. I took the carbs apart and cleaned them. I got it to the point that it would start but only 1 and 2 were firing. I finally got it to the point that 3 would also fire. I tried taking it apart and fiddled some more and then I couldn't get it to fire up at all. I got so frustrated that I pushed it onto my truck and dropped it off at the shop. 3 1/2 hours of labour later they got it running and synced the carbs.
This is my problem. It does start but is really sluggish until it is really warmed up. In fact it will even back fire on me sometimes if I don't start off with it revved up to 3 or 4 thousand rpm when I am first starting off. I am warming it up enough to turn the choke off before I am starting.
Here is some info that may have some affect.
It has been 5-10 celsius 40-50 farenheit.
I don't have an air box but individual air filters.
Supposedly it was ported previously
I do not have the fuel line octopus. I just have 2 lines that connects the tank to the carbs
I have noticed that it can be a little sluggish even at 4000 rpm if I am on the highway and at a constant cruising speed.
My first bike for the first 10 years was an '82 XJ 650 and I would expect them to run similarily but with the XS having more pep.
Any suggestions will be greatly appreciated. I had sold my XJ about 3 years ago and have been bound to 4 wheels until now. I really would like to resolve these issues so that I can get rid of my frustrations and be left with the excitement of being back on two wheels.

Thanks

[Ken Talbot]

If you are new to the XS11, you could be running with two dead cylinders due to a broken pick-up coil wire and you wouldn't know the difference. More likely, you need to do at least one more carb cleaning. When these bikes sit for a few years, the carbs will plug up in all sorts of fine orifices. Until they are absolutely clean, and that means every jet has to be completely removed, and cleaning wires and solvent and compressed air run through every passage, they will simply not run properly. Once you get it right, you will find almost no similarity to the performance of a 650. Have patience, but keep at it.....

[TopCatGr58]

Hey there JoeJoe,

Okay, first, you may want to find out IF that shop put any parts in, and if they used K&L kits, cause the pilot jets are the wrong ones, way too rich, which are notorious for causing excessively rich conditions in the pilot circuit which also affects the throttle response even around 4K, hence possibly a reason for poor throttle roll on.

Secondly, the pilot screws/idle adjusting screws that are on the top of the carbs in a small round hole right next to the intake mounts, were capped off in the 80-81 series carbs with a brass plug. So... if those have NOT been removed, then the pilot/idle circuit has NOT really been thoroughly cleaned, and you'll need to drill them out and remove them to be able to remove the pilot screws as part of a cleaning process.

Well, with the heads being ported, that should just help the flow, but might even make it lean, depending on what the mains are, would be nice to know what size your main jets are. But right now, it sounds like it's actually too rich in the pilot circuit, which does contribute a fair amount to the low/mid throttle range!!

Now that the carbs have been synched, you can take them off the bike as a complete set, leave them attached to the bracket, and you won't loose much of the synch adjustment while you clean them. Just some of my thoughts!?
T.C.

[joejoe]

Thanks for the input. So the outside temperature shouldn't affect it much? I went out to a movie with my wife and it was being a little sluggish. On the way home though it had cooled down a few degrees and was really windy. The bike behaved a lot worse under these conditions. When I called the shop and told them of its behavior when I first got it home they suggested that the temperature (it was below freezing at the time) probably was causing the problem.
I think that the only parts that the shop put in was gaskets on the intake valves because I guess that they were leaking. The shop supplies total was only about $26.00.
As for the coils I have replaced both with dyna coils so there shouldn't be any problem there.

Thanks

[TopCatGr58]

Hey there again JoeJoe,

Now hold on a minute, the cold air can be a factor, but only to a point of it warming up a bit. The colder/denser air requires more fuel to mix with it and the cold engine needs that as well until the internal operating temps reach nominal, so that's why the fuel enrichment circuit/choke!

An ambient temp of 40-50 degrees should actually help it to run cause it will provide a better cooling effect vs. 80-90 degree temps. A few years ago on a rally ride to Alexandria Bay, NY, I drove all day from Va. in May, got near Lake Ontario, 30 mile an hour crosswind coming off the lake, temps in the 40's, and the bike ran just fine for hours, although I about froze to death!

You mentioned 4K rpm, that's a really barely above the lugging rpm, and so if it's very cold, and it's not warmed up enough, and you're in high gear at 60+mph and trying to roll on from 4k, yes, I would expect it to act sluggish as well.

With those previous problems with only 2 firing, but on the same side, kinda rules out the ignition system, but what Ken was talking about was the PickUp coils on the left engine side under the timing cover, which controls the signals to the TCI and the main ignition coils, but would effect cylinders in pairs of 1-4 and 2-3.

As for the parts, there aren't any "Gaskets" on the valves, intake or exhaust, but there are valve stem seals, but that would involve pulling the head, cams, etc., to replace along with much more time$$ so I doubt that was it!? You will probably need to pull the gastank, fully empty it out, even use some Sea Foam mixed in there to further clean it out, and drain it using the RESERVE valve to remove built up gum/varnish and even rust particles from innards, then install some inline fuel filters.

Then after recleaning the carbs, put some fresh gas, and Sea Foam in the tank and run a tankful thru it, and add Sea Foam every few tanks thereafter to help keep it cleaned out!

Check your vacuum hoses for cracks, especially the one to the vacuum modulator on the ignition side, if it's leaking, it will cause poor off throttle/roll on response. Should probably replace the fuel lines as well ensuring there aren't any kinks or big dips/bends running too far below the carb bodies!
Keep at it! Your statement about a little more "pep" will be rather "under"stated once you get ALL of the HORSES unleashed in this wonderful machine!!
T.C.

[joejoe]

Maybe there shouldn't be gaskets on the intake valve. But I can see that they used a liquid gasket on them against the engine and they had mentioned that as well.
As I am sure you can tell, I am far from a mechanical expert. Although a have probably quadrupled my knowledge in the past month. Sorry for my coil mixup. I had learned that the ignition coils fired 1&4 and 2&4 simultaniusly. I don't have the problem with it not firing on all 4 cylinders anymore. I think that it was the carbs for those cylinders weren't cleaned well enough yet.
So on a cool day, should my bike be able to warm up enough just idling or would you suggest that I would need to get a few blocks under me before it will start to warm up to optimal operating temperature.
Another question for you. I understand that the air pressure here is between 13.5-14 psi. So my compression should be 121-126. I am getting 136 on 1 and 2. I ran out of time last night and haven't checked the other 2 yet. Is the high reading a good sign, a bad sign or anything I should be reading into this.

Thanks

[randy]

joejoe,

More important than the compression number itself, is that all four reading should be within 10%. For instance 150PSI + / - 15PSI.

This will help ensure a smooth running engine.

[TopCatGr58]

Hey JoeJoe,

Surprisingly, compression ratios and calculating PSI values from atmospheric pressure doesn't work exactly. Stock values are around 142 plus/minus 14. Like Randy said, better that they are within 10% of each other. However, those values are pretty good.

As for the alleged gaskets, I think you're talking about the Intake manifolds, the rubber parts that mount to the head, and have the carbs mounted to them. A vacuum leak could have caused you some problems, and they may have found or suspected that when they were working on the carbs!?

Most folks don't necessarily wait for the bike to reach full warmed up temps, once you get it running, you can drive it, just need to push the choke lever in after a few minutes. It's a two stage choke, so usually using the full amount to get it started and then pushed in to stage 2 when you drive off, and then all the way in soon thereafter. But, some wait until the idle starts to rise on full choke, then stage 2, and then again wait until idle starts to rise, then all the way in and drive off!? Your choice.

Congrats on getting it running better, again highly recommend the Sea Foam to further assist in the cleaning process!! Enjoy!
T.C.

[joejoe]

Sorry, I meant intake manifolds. As I mentioned earlier I am new to this mechanic stuff. Although I am not calling anything gizmos and thingamabobs. Thanks for your patience with me.
Your last reply T.C. brings up another issue. I may have lost something on the choke when I took the carbs off the first time as I now have to hold it or it turns off. So when I start it I shove a stick in to wedge it on. I imagine that it would help to have the two stage system working properly so that I could start off with it on the second stage as you mentioned. This is what I used to do with my maxim and it worked great. Although the engines appeared to be designed very similarily I do realize that I should not assume that if something worked for the old bike that it will work for this one.

Thanks again

[TopCatGr58]

Hey Joe,

You probably did loose something, there is a spring and bb type ball that fits into a little hole on IIRC the #1 carb body, where the choke actuating rod is, there is a little indent on the back side of the rod, and the bb presses into it to hold it in position. With it out, there's nothing holding the rod, so the spring tension keeps pulling it shut. You may be able to find some replacements?
T.C.