It's Greatest Wish Seems to be to Become a Static Display...

[Joab]

So, this 1979 XS1100SF, will not stay running. I bought it from a co-worker for 600, and I knew it would need work. I have carb rebuild kits coming, and a fairing and a set of petcocks off ebay.

My question, is there something else I should be looking at? Here is the issue.

The bike will only start if I hold the choke completely open. Its between 95-98 degrees outside, it will not even debate starting without the choke completely open.

The bike runs rough, and will sputter, and if God shines down on me, it will run for about 2 minutes, before finally giving up the ghost.

I have added Seafoam to the tank, and sprayed carb cleaner when I first picked it up.

As soon as the parts arrive, I will dig down and rebuild the carbs, and replace the petcocks. Is there anything else I'll need to look at? The guy I bought it from said the bike always ran and started great...a year ago.

Thanks for any light you can shed on the issues!

[CatatonicBug]

Sounds like a classic clogged carbs problem. These bikes will usually need the choke pulled for a bit to start, even in hot temps, but should at least TRY to start without it. Be sure to clean the carbs out thoroughly, then let us know if that improved the situation. Chances are, you don't need to wait for the kits, and can just clean the existing parts very well, and re-use them. Even the bowl gaskets can usually be re-used many times.

[Joab]

I'll give that a try this weekend then, if the kits haven't arrived yet. One more question. This interesting four position petcock...I take it in the up or down position, it isn't supposed to drain all the fuel onto my garage floor, right?

[bikerphil]

This interesting four position petcock...I take it in the up or down position, it isn't supposed to drain all the fuel onto my garage floor, right?

Lol, No. Your floats are probably stuck. Clean your carbs but remember not to dip them in caustic carb cleaner, very bad for the rubber seals.

[jetmechmarty]

In addition to the stuck floats and gummed up arteries in your carburetors, they probably also leak air at the butterfly seals and carb boots.

You can find the air leaks with a flammable aerosol like WD40 if you can keep it running long enough. Just don't set the bike on fire!

[DGXSER]

The four positions are...starting at 12:00....Reserve, then to the rear of the bike is Prime, down is ON and to the front of the bike is OFF.

If it is factory routed fuel system, it will have a vacuum operated valve over carb no 2 (commonly called the Octy or Octupus) that shuts off fuel when not running.

As Phil stated, if fuel is running all over out the air box, then you have a float valve stuck in one or more of the carbs. Like Bug suggested, take the carbs off and start the cleaning process. Even with new parts, you will need some time to clean the carb bodies, and passages properly. So start now and clean everything REALLY well.

Most folks use some brushes and spray carb cleaner along with some compressed air to clean them out completely. Do a search for "Carb Cleaning 101" and you will find some great info on how to dismantle and clean them up.

[natemoen]

And if your dumping gas out the bottom of the air box its also possible that your dumping gas into your cylinders and then its contaminating your oil. If your oil level seems to be getting higher it means there is gas in it. either way be careful not to run the bike if you get gas in the oil.

[Joab]

I'll have all weekend to mess with the fuel system on this thing, and get get everything looking pretty again. If the carbs arn't any more complicated then what the XS650 is running, it shouldn't be too bad. Since it hasn't probably had an oil change in a good year or more, I'll get that done also...after I fix the whole dumping fuel issue

[yamtom]

oil gas check

Hi,

Regarding the gas in oil issue, the litmus test as explained here often, is to stick something in the oil , a small stick or wire , pull it out, take it far away from other flammables etc, then light the oil with a match or lighter, if the oil catches fire, there is gas in the oil, if it does not catch fire, there is no gas in the oil.

[jetmechmarty]

Joab,

Carbs are nearly identical to XS650. Just don't interchange them. I learned it doesn't work well.

[Joab]

Yamtom- I will try the trial by fire trick tomorrow.

Marty - No fear of mixing the carbs, the 650 is in about a thousand pieces and five boxes in Minnesota still, at least for another couple weeks. After that, ill have to be careful with where I put what.

[Cobia]

Joab,
You don't usually have to take the carbs off the rail brackets unless you have a butterfly seals or choke seals problem. Just take them apart individually and return the parts where they came from. I use numbered 16oz plastic cups (beware, they don't like gasoline very much) for each carb. The inexpensive ($2) carb spray cleaner from wally world or Advance auto works great. Count on using about three cans and use eye protection and nitrile gloves. That shiite burns like a MF. After you visually confirm that cleaner is coming out of at the other end of all of the circuits when you spray it with the straw, then you're ready to re-assemble. And don't forget the choke circuit at the bottom of the float bowl, it can be a biatch.

[XS1100_OEM4ME]

Clean

So, this 1979 XS1100SF, will not stay running. I bought it from a co-worker for 600, and I knew it would need work. I have carb rebuild kits coming, and a fairing and a set of petcocks off ebay.

My question, is there something else I should be looking at? Here is the issue.

The bike will only start if I hold the choke completely open. Its between 95-98 degrees outside, it will not even debate starting without the choke completely open.

The bike runs rough, and will sputter, and if God shines down on me, it will run for about 2 minutes, before finally giving up the ghost.

I have added Seafoam to the tank, and sprayed carb cleaner when I first picked it up.

As soon as the parts arrive, I will dig down and rebuild the carbs, and replace the petcocks. Is there anything else I'll need to look at? The guy I bought it from said the bike always ran and started great...a year ago.

Thanks for any light you can shed on the issues!

Shut that bitch down IMHO. R/I carbs, clean, then clean again. Make "sure" everything is set to "exact" spec, float hight, jet size. mid needle hight. "CHANGE YOUR OIL". If you have run with bad carbs, you could/prob. have some gas in your oil. Sync. carbs with gage's and color tune plugs after some miles to see how your work is doing

[fredintoon]

I'll give that a try this weekend then, if the kits haven't arrived yet. One more question. This interesting four position petcock...I take it in the up or down position, it isn't supposed to drain all the fuel onto my garage floor, right?

Hi Joab,
if the gas is dripping out of the airbox one or more of the carb floats is sunk.
If the gas is pouring straight out of the gas tap spigots you have amateur night at the octopus valve.
Some folks love the octopus. Others toss it away and run 2 fuel lines instead of 9.
Ask the search function about the octopus valve and see what is said.

[Joab]

Ok, well, it looks like I am going to need a synch tool for when I put everything back together. Will this work?

http://cgi.ebay.com/ebaymotors/CARB-...motiveQ5fTools