Carburation

[DGXSER]

Cobia, thanks for the suggestion. I am right at the thread area now and do not want to risk tearing up the threads, besides, if the extractor broke off rather than breaking it loose, how tight must it be siezed up in there. I think any slot I cut will simply tear out again.

Mick,
thanks for the suggestion as well. I just put the headers back on with new gaskets and this has been through a couple tanks of gas from different stations. It has always popped on decel since I got it. And that was the first ride long enough for me to notice the slight studder at 2500-3000 RPM. Carbs are completely torn down except for this bloody dang mixture screw that won't give up and come out.

[bikerphil]

carb screw tower

As a last resort, I've heard of people cutting about a 1/4 inch off the pilot screw tower to be able to grab the screw head with a vise grips.

[MickT]

Ive done a few sets of them carbs, not a good thing to cut the carb body, I drilled out a pilot screw, have to be very very carefull , then taped out the body with a M8 tap, then used a float bowl drain plug to make an insert then re taped with a M6 tap same thread as the pilot screw 0.50 thread, when you drill it out us a 5mm drill bit, got to be dead square and streight but only drill down to the spring or you will ruin the carb all together




pic of insert


you might be able to save yourself from the insert trick if you are very carefull

[MickT]

CLICK HERE also find the info on here XS1100 UK forum

[skids]

Man, you could have been a brain surgeon! That is a great idea about using a plug and tapping it!

[DGXSER]

Again, thanks for the excellent suggestions. I wonder if someone welded the blinkin thing in place. Why the other three backed right out (after I counted the turns to bottom for resetting) and this one will not budge I wonder if it is cross threaded to start with.

I have measured the height of what is left after using a bur to cut a new groove more than once before I resorted to the extractor. In order to get low enough to get a grip on anything I would be into the threaded area. I am not to worried about tearing up the upper shaft above the threads, as it is just there as a guide and to put the factory cap on.

Mick, that is an excellent idea, however, I lack the tools required to be that precise in my drilling. At this point I think it will take an end mill in a good machine to drill both materials out that accurately. I don't have a drill press of any kind, so I am concerned anything I do will slip off the extractor for the brass and be off center or even into the aluminum. Even adding the plug, it needs to be a centered hole.

[Ivan]

see if you can find a machine shop, and ask if they can center drill it for you.



they make several sizes, and one would fit close enough to the tower hole that it wouldn't walk. this will get you a start on drilling and extracting.

[dbeardslee]

Don - If you really get in a fix, I've got some carb bodies off a special out in the man cave as well as a bunch of other parts. I might have some mixture screws for a special also. I don't know why I didn't think of 'em before. Completely disassembled and cleaned this past summer - then put 'em on a shelf and promptly forgot about 'em. I had three complete carbs when I started, so there should be parts for three out there now. If you change the bodies, you'll have to take the carbs off the rails - something I haven't done yet, but how hard can it be . Let me know.

[DGXSER]

I called a local shop who wants to look at ti and see if they can get it out for me.

Dbeardslee,
Thanks for the offer again! I will definitely give you a shout if I can not find a way to get this thing out.

[DGXSER]

Dahmik

Well,
It appears I should have left well enough alone. Now No.4 is cold at idle (it is the one with the mixture screw stripped off.) I decided after talking to several shops in town to try running it liek it is.

I got the rebuild kits today, installed all the new parts, reinstalled all of the old ones. checked the floats with a go-no go gage, they all were good. I did skip the bench test as I do not have a way to do that myself.

I got the carbs back ont he bike, everyhting hooked up, checked for fuel in all the bowls, fired it up and it ran pretty strong. Idles much higher than before, so I set the idle back down (not sure if it got changed durign all the car rides to the shops to see if anyone could get the screw out.).

Misses badly at low end under any kind of load. higher RPMs is better but still feels not quite there. I think I need to remove it all and get that #$%^^&##%^%^$^ screw out!! Maybe a local machine shop can help, or I may need to get ahold of DBeardslee for those spares he has.

Anyway, the fun of trying to fine tune something and making it worse. I almost know how Crazycnuk felt. (Almost, I read that whole thread, man did he fight it hard.)

[oldyam80sg]

Did you try the bread tie sync?I'm curious because i tried it, and it made the difference between riding and not riding.I had to turn down the knob because of the high idle, but other than that it got me by until i was able to sync properly.I don't know if i would ride it with #4 pipe being cold,i can personally tell you that with #2 not working because of crap underneath the needle valve it felt like riding a moped.I would wait until you get that screw out.My problem happened just when the weather was nice enough to ride.Remember patience.

[DGXSER]

Actually, idle is where it is best, sounds relatively ok. I rode the bike about five miles total round trip. Below 3500 it has no power and really rough. Above 4000 it starts to get power, above 5 it pulls like mad. Then at idle it does not sound to bad, but under load of any kind below about 4,000 it misses.

The more I think about it the more this sounds like pilot circuit issue. I have all new pilots, all new mains, all new float needles and seats. No 3 and 4 plugs look a little white on the sides of the electrode (not the center one).

The carbs are back apart, not sure how but I need to get that mix screw out now. No shop around me thinks they can get it, will try a local machine shop perhaps??

I also noticed that the springs on my new mixture screws are shorter than the ones on the existing/old mixture screws. Now I have to wonder what that will do to the mixture?? The screws are the same length, and I seated them then backed off to the setting before I took the carbs apart.

Like usual more questons than answers.

[DGXSER]

Ok, I have the K&L kits from George Fix on Ebay. I just spent an hour reading the different threads in the K&L kits including Proms research. I am not sure, but I think the holes in the sides of the pilots look smaller to me than the ones that were in there. I have also found that the needle end of the mixture screws is smaller ie...thinner, than the ones I had in there. Sooo, the idea of setting them where the old ones were set goes out the window as it does not equate to the same setting anymore if I am thinking this through correctly.

I am also very puzzled and concerned about this pilot jet issue. Two of my old ones got boogered up getting them out so I can't just go back to where I was.

[DGXSER]

Oldyam,

I did get a bread tie and tried to put it in, but I have no where near that gap. I did sync the carbs using a vacuum gage before I went to cleaning them, so I am thinking they should be reaosnably synced as is.

Step one is still get the old mixture screw out which is probably all buggered up from either the drill to put the extractor in, or the carb cleaner and PB blaster I tried to get backwards through the hole to free it up from the backside. right now, I think sleep is in order.

[DiverRay]

You can try to remove part of the tower with a dremel tool. Take to top down about 1/4", and the top of the screw should be easier to get at. Then use the diamond bit, as was mentioned, to put a new slot in the screw.