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Hello, XS/XJer's! I'm a new member, and this is my first post here, but I'm not new to using this forum or my XS1100 SH. I've had my 81 XS1100 Special since March of 1995... over 18 years now. It's all-stock: stock exhaust, fuse, airbox, etc... no custom upgrades, although tires and fuel lines aren't original, and seat was recovered. Aside from pulsating front brakes from day one and an odometer that's been stuck on 100 miles since I bought it, everything was just great until 2005.
I got it out that year, and it would only run on 3 cylinders. Ah, that's what I get for not prepping it for winters! So I tore down the carbs and cleaned all the jets in July of that year. Put it back together, fired up, ran all cylinders great as usual again! But oh no! The next time I go to ride, gas is all over the floor! OK, so something must have gotten stuck in the seat, so I better turn off the petcocks for now. But I found it did the same thing even if the petcocks were set to "off." Pulled the carbs again, cleaned out the seats again, and used the off-bike float level test. No go - still overflowing on one or more carbs. So I didn't even bother installing the carbs and set everything aside storing the bike in my walk-out basement.
In May of 2006, I ordered all new needles, seats, o-rings, petcocks/octopus rebuild kit. But the bike continued to sit in my basement for just over 8 years with no carbs on it, no type of storage prep. I had intended to get back to it years sooner, but time got a way from me at I involved myself with other interests, and it wasn't until a week ago that I finally took a wrench to those carbs again. I completely disassembled short of the butterflies/throttle shafts. After soaking metal parts in carb cleaner (not the bodies) and then cleaning & verifying all passages on carbs were clear, I reassembled. I, of course, verified the float levels and that it wasn't leaking using the off-bike method shown on this forum... using a level, transparent tubing, taking care to get accurate readings after allowing the fuel to resettle after moving the tube up/down. It looked good, just like here:
http://www.xs11.com/forum/showthread.php?t=76
Plus... no more leaks!
There was some rust in the tank, so I treated that by rotating the over several days using Evaporust - it worked, and I installed rebuilt petcocks and added gas. I was concerned about the cylinders/rings/pistons after being in one position for 8 years, so I let some penetrating oil soak in the cylinders for a day, then got out all I could, and verified the engine turned by hand. After charging the old battery with a slow charge, it cranked it well also. OK, so I installed the carbs (was much more difficult this time), hooked up new fuel lines, the gas tank, installed the plugs, and finally fired it up. There was some heavy blue smoke for a while, and I let it warm up a while... still running rough. Then I changed the oil and filter... putting in 20W50.
After that, it still smoked after it warmed up out of the left exhaust, even after a short ride, but then I took it for a 20 mile ride, and it performed mostly well, except when RPMs got down around 2000 rpm, a little hesitation and lack of power. At 2500+, it was pretty good... as I remembered it. And the next time I started it and let it warm up, it no longer smoked, either! What was really bothering me was that while idling, the throttle would no longer pop up instantly like it used to. It would hesitate before increasing rpms at a slower increase in RPMs than it used to, just as the lower RPMs shows hesitation and performance issues on the ride. And the idle wouldn't lock-in and stay consistent if left idling after warming up. I hoped some minor mixture adjustments and carb sync would dial it in.
The plugs looked lean across the board to me, so I enriched the mixture. Then I did the carb sync and brought them all in line, even swapping guages to verify consistency. The problem is... that didn't help at all with the low RPM hesitation and idle issue I was having. Another 1/4 turn on the mixture screw seemed to make no difference, which was then 1/2 turn richer than when I had torn it down to begin with. The fuel enrichment circuit would bring the RPM's up above 2000 rpm, so that wasn't helpful for comparing throttle response, which was pretty bad around 1000 to 1500 rpm.
Since I had meticulously verified the float fuel levels off the bike, I knew I was good there, so I read a LOT of posts here on the subject. Beyond what I had already mentioned, common responses to people reporting similar problems with various years/models here were suggestions regarding the intake boots leaking, vacuum hoses attached incorrectly, obstructed carb passages/jets, pickup coil wires, pickup coil gap, ignition coils, TCI, broken mixture screw tips, missing/bad mixture screw o-ring, leaking diaphragms, weak diaphragm springs, incorrect jets, low compression (rings/valves), fuel feed/octopus, petcock position, valve adjustment, plugs, plug gap, plug wires, bad/E10 fuel, air filter, nest/obstruction for air intake, ignition advance, timing problem, incorrect jets, incompatible air filter pods, tipover switch, fusebox, bad electrical connections, use SeaFoam, ride 200 miles to unstick rings (after sitting for years), needle jet adjustment, ballast resister.
Well, I used the techniques recommended to check for vacuum leaks and pretty much figured I had already addressed all the carburetor possibilities. Same jets, etc. had been working great in 2004. So I put a timing light on the #1, then #2 plug wires and watched it fire as someone had suggested... looking for inconsistency in the flashing. It looks like the flashing was cutting out for a fraction of a second at time, particularly when I gave it throttle at idle. Ah ha, so I must have an ignition problem, right where I'm seeing the biggest problem, when giving throttle at low RPM, and that common recommendation about checking the pickup coil wires looks spot on. So I unscrewed the screw holding the bundle of 4 wires together where they flex and pulled at each one while idling, the the engine didn't miss a beat. It was late, and I repeated that test the next day, but it kept idling away. Then I did the timing light test again, and I didn't see the cut-out this time, at least, not much, even though the idling and throttle off idle was crappy as always. OK, so now I'm back to the fuel system again.
Since I thought it was running lean, I did a few tests where I sprayed some starting fluid in the air intake during idle while immediately giving it heavy throttle. The engine revved up instantly as I had so fondly remembered.
I repeated that a few times successfully. But within seconds of stopping with the starting fluid, it was back to a hesitating weak throttle off idle.
Although I had meticulously checked my float levels using the off-bike tube technique, I figured I would go ahead and check again... now on-bike. What the????
On the center stand in my garage, the levels in all carbs were about 9mm lower EACH than they had been from my off-bike test prior to installing the carbs. I moved the tubing up and down to verify it was settling at this significantly lower float fuel level. Then I put some boards under the front tire to get the carbs level from front to back, and that narrowed the gap a little, but it was still about 7mm lower than my off-bike measurement, meaning 7mm below spec. The carbs are warmer now, but I don't see how that would account for this. This is specifically what I had taken extra time in advance to prevent. 
The only thing I can figure is that I knocked my level off during my pre-mount test, but I didn't even get one carb right. That was very surprising. I'm on the right track here, aren't I?
Well, it seems being that low in float fuel level would certainly explain idle and low-rpm issue, which I suspected was a lean fuel mixture as mentioned above. But that means I'll need to pull the carbs again.... which I did NOT want to do. And speaking of the carbs... when I reinstalled them after my first cleaning back in 2005, I didn't have that much trouble getting them back on. But this time, after having the carbs off the bike for 8 full years, they would not go back on completely. The boots must have contracted and/or stiffened over 8 years without having carbs in them.
I read over some tips about applying lubrication and watched the youtube video about installing carbs linked from this site, but none of those were helping at all. After doing the airbox side successfully with the airbox remaining loosened, the engine side of the carbs would go into the boots a short ways, just short of the groove on the carb. I couldn't get them in any further. The boot clamps were very loose, there were no obstructions, the airbox and carbs weren't being obstructed by anything that I could see. I verified all 4 carbs were just inside each of the boots' full circumference. Trying to beat it in with the palm of my hand, rubber mallot, block of wood, the aid of lubrication over the contact area... nothing was working. I spent quite a while and broke out in a sweat multiple times in frustration.
Then I thought to try using a 5 ft long 2x3 that I had lying around, and I put one end down by the foot peg and the middle area against the edge of the carbs, and I used my shoulder to put some force on the upper part of the 2x3 to get leverage, and the carbs went right in the rest of the way! 
I hadn't seen this tip suggested anywhere, but it sure helped in this situation, and I preferred that over beating on the carbs as shown in the video in the first place.
About those pulsating front brakes... well, the front brake are soft compared to what they used to be, and there isn't any pulsating now. After braking, both disks feel equally warm. Anyway, after 8 years of sitting, I know the all brakes needs disassembled and a thorough cleaning along with new brake fluid. My very first internet search on the XS1100 back in the 90's was regarding sticking brakes, when I found out about the tiny hole that gets clogged up.
Anyway, this forum has been a great resource. I got some good ideas from this site. If there's one thing frustrating about the forum, it's when you're following a thread where someone with a problem is getting various suggestions, so you're reading along anxious to see what the solution is, only to see the thread end... unknown as to what the fix was. Oh well. The suggestions and info given are valuable none the less. So thanks to all of those who have helped out.
I got it out that year, and it would only run on 3 cylinders. Ah, that's what I get for not prepping it for winters! So I tore down the carbs and cleaned all the jets in July of that year. Put it back together, fired up, ran all cylinders great as usual again! But oh no! The next time I go to ride, gas is all over the floor! OK, so something must have gotten stuck in the seat, so I better turn off the petcocks for now. But I found it did the same thing even if the petcocks were set to "off." Pulled the carbs again, cleaned out the seats again, and used the off-bike float level test. No go - still overflowing on one or more carbs. So I didn't even bother installing the carbs and set everything aside storing the bike in my walk-out basement.
In May of 2006, I ordered all new needles, seats, o-rings, petcocks/octopus rebuild kit. But the bike continued to sit in my basement for just over 8 years with no carbs on it, no type of storage prep. I had intended to get back to it years sooner, but time got a way from me at I involved myself with other interests, and it wasn't until a week ago that I finally took a wrench to those carbs again. I completely disassembled short of the butterflies/throttle shafts. After soaking metal parts in carb cleaner (not the bodies) and then cleaning & verifying all passages on carbs were clear, I reassembled. I, of course, verified the float levels and that it wasn't leaking using the off-bike method shown on this forum... using a level, transparent tubing, taking care to get accurate readings after allowing the fuel to resettle after moving the tube up/down. It looked good, just like here:
http://www.xs11.com/forum/showthread.php?t=76
Plus... no more leaks!
There was some rust in the tank, so I treated that by rotating the over several days using Evaporust - it worked, and I installed rebuilt petcocks and added gas. I was concerned about the cylinders/rings/pistons after being in one position for 8 years, so I let some penetrating oil soak in the cylinders for a day, then got out all I could, and verified the engine turned by hand. After charging the old battery with a slow charge, it cranked it well also. OK, so I installed the carbs (was much more difficult this time), hooked up new fuel lines, the gas tank, installed the plugs, and finally fired it up. There was some heavy blue smoke for a while, and I let it warm up a while... still running rough. Then I changed the oil and filter... putting in 20W50.
After that, it still smoked after it warmed up out of the left exhaust, even after a short ride, but then I took it for a 20 mile ride, and it performed mostly well, except when RPMs got down around 2000 rpm, a little hesitation and lack of power. At 2500+, it was pretty good... as I remembered it. And the next time I started it and let it warm up, it no longer smoked, either! What was really bothering me was that while idling, the throttle would no longer pop up instantly like it used to. It would hesitate before increasing rpms at a slower increase in RPMs than it used to, just as the lower RPMs shows hesitation and performance issues on the ride. And the idle wouldn't lock-in and stay consistent if left idling after warming up. I hoped some minor mixture adjustments and carb sync would dial it in.
The plugs looked lean across the board to me, so I enriched the mixture. Then I did the carb sync and brought them all in line, even swapping guages to verify consistency. The problem is... that didn't help at all with the low RPM hesitation and idle issue I was having. Another 1/4 turn on the mixture screw seemed to make no difference, which was then 1/2 turn richer than when I had torn it down to begin with. The fuel enrichment circuit would bring the RPM's up above 2000 rpm, so that wasn't helpful for comparing throttle response, which was pretty bad around 1000 to 1500 rpm.
Since I had meticulously verified the float fuel levels off the bike, I knew I was good there, so I read a LOT of posts here on the subject. Beyond what I had already mentioned, common responses to people reporting similar problems with various years/models here were suggestions regarding the intake boots leaking, vacuum hoses attached incorrectly, obstructed carb passages/jets, pickup coil wires, pickup coil gap, ignition coils, TCI, broken mixture screw tips, missing/bad mixture screw o-ring, leaking diaphragms, weak diaphragm springs, incorrect jets, low compression (rings/valves), fuel feed/octopus, petcock position, valve adjustment, plugs, plug gap, plug wires, bad/E10 fuel, air filter, nest/obstruction for air intake, ignition advance, timing problem, incorrect jets, incompatible air filter pods, tipover switch, fusebox, bad electrical connections, use SeaFoam, ride 200 miles to unstick rings (after sitting for years), needle jet adjustment, ballast resister.
Well, I used the techniques recommended to check for vacuum leaks and pretty much figured I had already addressed all the carburetor possibilities. Same jets, etc. had been working great in 2004. So I put a timing light on the #1, then #2 plug wires and watched it fire as someone had suggested... looking for inconsistency in the flashing. It looks like the flashing was cutting out for a fraction of a second at time, particularly when I gave it throttle at idle. Ah ha, so I must have an ignition problem, right where I'm seeing the biggest problem, when giving throttle at low RPM, and that common recommendation about checking the pickup coil wires looks spot on. So I unscrewed the screw holding the bundle of 4 wires together where they flex and pulled at each one while idling, the the engine didn't miss a beat. It was late, and I repeated that test the next day, but it kept idling away. Then I did the timing light test again, and I didn't see the cut-out this time, at least, not much, even though the idling and throttle off idle was crappy as always. OK, so now I'm back to the fuel system again.
Since I thought it was running lean, I did a few tests where I sprayed some starting fluid in the air intake during idle while immediately giving it heavy throttle. The engine revved up instantly as I had so fondly remembered.
I repeated that a few times successfully. But within seconds of stopping with the starting fluid, it was back to a hesitating weak throttle off idle.Although I had meticulously checked my float levels using the off-bike tube technique, I figured I would go ahead and check again... now on-bike. What the????
On the center stand in my garage, the levels in all carbs were about 9mm lower EACH than they had been from my off-bike test prior to installing the carbs. I moved the tubing up and down to verify it was settling at this significantly lower float fuel level. Then I put some boards under the front tire to get the carbs level from front to back, and that narrowed the gap a little, but it was still about 7mm lower than my off-bike measurement, meaning 7mm below spec. The carbs are warmer now, but I don't see how that would account for this. This is specifically what I had taken extra time in advance to prevent. The only thing I can figure is that I knocked my level off during my pre-mount test, but I didn't even get one carb right. That was very surprising. I'm on the right track here, aren't I?Well, it seems being that low in float fuel level would certainly explain idle and low-rpm issue, which I suspected was a lean fuel mixture as mentioned above. But that means I'll need to pull the carbs again.... which I did NOT want to do. And speaking of the carbs... when I reinstalled them after my first cleaning back in 2005, I didn't have that much trouble getting them back on. But this time, after having the carbs off the bike for 8 full years, they would not go back on completely. The boots must have contracted and/or stiffened over 8 years without having carbs in them.
I read over some tips about applying lubrication and watched the youtube video about installing carbs linked from this site, but none of those were helping at all. After doing the airbox side successfully with the airbox remaining loosened, the engine side of the carbs would go into the boots a short ways, just short of the groove on the carb. I couldn't get them in any further. The boot clamps were very loose, there were no obstructions, the airbox and carbs weren't being obstructed by anything that I could see. I verified all 4 carbs were just inside each of the boots' full circumference. Trying to beat it in with the palm of my hand, rubber mallot, block of wood, the aid of lubrication over the contact area... nothing was working. I spent quite a while and broke out in a sweat multiple times in frustration.
Then I thought to try using a 5 ft long 2x3 that I had lying around, and I put one end down by the foot peg and the middle area against the edge of the carbs, and I used my shoulder to put some force on the upper part of the 2x3 to get leverage, and the carbs went right in the rest of the way! I hadn't seen this tip suggested anywhere, but it sure helped in this situation, and I preferred that over beating on the carbs as shown in the video in the first place.About those pulsating front brakes... well, the front brake are soft compared to what they used to be, and there isn't any pulsating now. After braking, both disks feel equally warm. Anyway, after 8 years of sitting, I know the all brakes needs disassembled and a thorough cleaning along with new brake fluid. My very first internet search on the XS1100 back in the 90's was regarding sticking brakes, when I found out about the tiny hole that gets clogged up.
Anyway, this forum has been a great resource. I got some good ideas from this site. If there's one thing frustrating about the forum, it's when you're following a thread where someone with a problem is getting various suggestions, so you're reading along anxious to see what the solution is, only to see the thread end... unknown as to what the fix was. Oh well. The suggestions and info given are valuable none the less. So thanks to all of those who have helped out.
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