Compression problem

[B.B.]

Thanks everyone for the help. I will have the carbs back off today HOPEFUllY (between church) and take some pics. I did some research last year and thought that the carbs were original. I thought it said the 80 xs special had the plastic floats and did not have the rubber plug in the pilot jet but with the pics I post you can tell me for sure(since I usually don't know what i am talking about).

DGXSER-to your questions. I removed and cleaned the jets with the bread wire like the forum suggest and cleaned every orifice I could see and get to. I replaced the O-rings but did Not replace the float neddle valve or the seat. Were can I get them? Also to your Q's "As to the idle (You do know about the choke/enrichment, yes? You did clean out the enrichment jets in the bowls, yes?" I am not sure were that is exactly but like I said I removed everything and gave it a good cleaning.

Since yesterday the carbs leaked very little and a few taps with the screwdriver staightened it right up. I left the petcocks on all night and no leak. Yeah.

I put seafoam in the gas tank and put some in the crank case oil. After doing that the bike did not smoke nearly as bad from the exhaust pipe or were it connects to the cylander. But it smoked a lot from the breather hose. Not sure what that means? Was going to try and fog the carbs like the form suggest but can not find the seafoam creep stuff anywhere in our area.

Just an update so far. The carbs are not leaking now the bike cranks and idles low for a couple minutes while I tweek the throttle to keep it running. then it picks up and idles high for about 5 to 10 minutes then idles way back down and wants to die again. And it seems to be running rough.

Thanks again for the help I will post pics of the carbs and we can start over. Hopefully with some better results.

[DGXSER]

Ok, first off, you do not want to put load on the engine with the seafoam in the oil. Run the engine at idle for about 15-20 minuted then dump that oil and put fresh clean oil and filter in.

You may get away from replacieng the needle and seat, but I would anyway. If not now, you will probably need to in a year or two. Several places to get them, Parts-n-more, ebay, I think bikebandit or any of those will have them.

As to the enrichment jet, if you look in the float bowl, in the bottom, you will see a little nipple with a hole in it. That is the jet I speak of. It connects to the hole in the edge of the float bowl where the brass nipple on the carb body goes in. That jet often gets plugged up.

If you have not cleaned that jet, and they are plugged or dirty, then you will not get enough fuel till the engine gets good and warm. In that case, you may have your idle set up real high for warm operation to keep it running till it warms up. Then it idles up high, and then if your mixture is off the plugs may be fouling. Have you tuned the mixture or synched the carbs? The bike will need to be good and warmed up for that process.

[WMarshy]

Remember to remove the emulsion tubes during your cleaning. There is a good maintenance thread with pictures on how to remove them without damaging them. You need to spend a little time in this section of the forum ...

http://www.xs11.com/forum/forumdisplay.php?f=30

Sounds to me like your sync is way out, rpm shouldn't drift very much if at all from cold start to warm idle

[GLoweVA]

Something else to add to the list of things to fix. Exhaust leak at #1 cylinder to header pipe. COuld just be a bad exhuast gasket or just a loose header flange.

The smoke coming from #1 and the lower compression from #1 means that's where your issue is. The smoke coming from the crankcase breather tube is from the same source. It sounds like the rings are not sealing well and you're getting blow by so there's the smoke into the crankcase and if the rings aren't doing their job then your probably getting some oil into that cylinder too.
Because you've got some compression (and not zero) and it's not backfiring then it sounds like the valves are seating correctly, so it's got to be the rings.

Check that spark plug and see if it's oily or gassy, white or black & sooty.
You may be able to get those rings in #1 to work themselves in okay.
If the engine had been sitting for years, at least one valve must have been open and it might have been #1 and thus that cylinder got a little rusty and the rings got 'frozen'.

[B.B.]

[QUOTE=GLoweVA;382848]Because you've got some compression (and not zero) and it's not backfiring then it sounds like the valves are seating correctly, so it's got to be the rings.QUOTE]

The bike does backfire.

I am about to take the carbs off and take pics. I cranked the bike today and it acts totally different. yesterday to start it you had to open the throttle all the way and when it cranked you had to rev the throttle to keep it running for a little bit and the it would idle up. Today I cranked it using no throttle and when you try to rev it up it would die. so i could not touch the throttle. But it idled good for a few minutes. Then died and I couldn't get it to start.

It ran for about 8 minutes and only smoked from the breather hose. Not from pipe or cylander 1. Just seems to change so much its confussing.

[DGXSER]

Did you get the Seafoam out of the crankcase, change the oil? You really do not want that stuff in there for long when running. It could be the source of your smoking form the breather. Other could be you over filled when you added the seafoam. Just thoughts on that.

Until you get the carbs sorted and somewhat tuned, starting and idling will be a mixed bag for sure.

[B.B.]

Ok so here we go. The carbs were pretty bad. hope this is what you need

[B.B.]

Does someone know were i can get the #4 carb and does it matter if it is the #4 or not? The float rocker arm is broke off of that one.

[DGXSER]

You definitely have the newer style carbs. Did you pull the emulsion tube out?, that is the part in the center tube that the main jet screws into. It pushes out the top of the carb.

As to the carb body, I do not have one. You could use a no 2 in a pinch, but you would need to plug the vacuum port for the vac advance on it. No1 and or No 3 would have hte fuel inlets on the wrong side. If you are really talented, you could probably drill out the fuel inlet on the opposite side and fill it in whre it is now. That would be outside my range of skills though.

[B.B.]

You definitely have the newer style carbs. Did you pull the emulsion tube out?, that is the part in the center tube that the main jet screws into. It pushes out the top of the carb.

As to the carb body, I do not have one. You could use a no 2 in a pinch, but you would need to plug the vacuum port for the vac advance on it. No1 and or No 3 would have hte fuel inlets on the wrong side. If you are really talented, you could probably drill out the fuel inlet on the opposite side and fill it in whre it is now. That would be outside my range of skills though.

OK since they are newer carbs can I find them easier? Because I deffinatly can not do what you were suggesting and only half of what you were saying to do.
And No I have not pulled the emision tube yet but I stopped tearing it apart so I could get the pics posted.
Thanks for letting me know about the carbs. Is it going to be a certian type carb that I need to look for?

[natemoen]

Those things are nasty looking! That broken post is a possible cause for the fuel leaks, but if the tips of those needles are hard they need to be replaced.

BUT we still don't know for sure what carbs they are we need to know if there is a hole that goes between the main jet tunnel and the pilot jet tunnel. That is the determining factor between the late model carbs and the hybrid carbs

[DGXSER]

True, they could be the "hybrid" or I like to call "bastardized" set from the 80 models. You have the later style carb bodies, and the float bowl drains would indicate they are the 80 models. In that first year for the new style, there were some sets produced with the same crossover between the pilot jet and main jet tunnels. The only way to know is to look in the tunnel to the pilot jet to see if there is an opening leading up toward that main jet tunnel, or remove the emulsion tubes (which you need to do anyway) and look for the hole there as well. I give it about an 85% chance there is no crossover, but I have seen one of these sets before. To get the emulsion tubes out I use a wooden dowel and hammer to drive them out, given the condition of the carbs, you will need to be driven out. When you go to pull the pins on the floats, there is a tool you can make designed by Ken that will keep you form breaking off the post.

There are several ways to repair the broken post (which I did not see any broken in the pics). But post in the parts wanted section for a no 4 carb body, someone may have one they will sell you.

[GLoweVA]

Brian, those carbs definitely need some serious cleaning!
As far as the smoking less now, that may just be the rings getting broken back in. You may find that your compression numbers are getting a little better now.
The backfiring could also be because of a too lean condition. By the look of those carbs, if they're not suppling enough fuel then you'd be too lean.

As far as the 1980 carbs, I've got a G and a SG and my G has the crossover hole and thus the plugs in the pilot jet, while my SG does not and no plugs.
Your pics show no rubber plugs there, so I'd assume you have no crossover hole, but the only way to be sure is to look once you get those emulsion tubes out.
I didn't see the #4 float post broken in the pics. Is it the pin or the support post?

Also when you go to break those things down for the cleaning, make sure you pull the idle mix screws out too. Check the tech section here for the carb cleaning 101 thread/post/sticky.

[crazy steve]

Carb ID guide.... http://www.xs11.com/forum/showthread.php?t=35964 ... and rebuild pictorial...http://www.xs11.com/forum/showthread.php?t=36017

[trdriver71]

i wouldn't worry right now about the smoke it is likely the atf that you put in the cylinders burning out anyway but you have to get those carbs cleaned.