New member here, just bought an xs1100 special

[cajun31]

As cajun31 pointed out, I missed checking the pilot screws in my carb rebuild. So today I took it off again, removed all the rubber parts and got to removing them.

All the parts looked good to my untrained eye, but I replaced everything anyway. This picture shows the old parts.

Two things happened that made the day interesting:

1. I checked the screws' positions before removing, and the #3 screw was all the way in. When I took it out, there was no spring inside!?! I'm convinced I just dropped it somewhere.
2. The #4 screw stripped. I ended up drilling it out, but I drilled off-center and couldn't use my screw extractor! 😬. As I began to panic, I decided to make decisions on how to fix it. If 1 hole got me in this mess, then a 2nd hole might get me out of it. So I drilled a 2nd hole next to the 1st one. Luckily, the two holes merged and created a new slot for me to use a screwdriver again. Luckily, it worked! I did score the edge of the hole a bit, but not enough to matter.

So with that tail-clenching fun behind me, I put the carb back together and reinstalled. I used a hanging gas tank with a splitter to see if removing the octy, plus the carb rework did anything.

After a few cranks, the bike fired up. Eventually, I could take it off choke, and even rev it! It was great to hear the sweet music. Keep in mind, I have yet to even ride this bike, and this was the first time I heard it in real life. I've had to resort to YouTube videos to watch others ride their XS.

I realized I didn't cap the old vacuum nipple, so that is next on the list, along with synching.

Also, it leaked gas as I tried restarting, but once it fired up, it stopped leaking. From what I can tell, it looks like it's leaking from the airbox? Wouldn't that mean the float valves are not working and the bowls are flooding? I replaced all those parts, and checked them, so I'd be surprised if they are the culprit.

Any thoughts?

Can honestly say have been there and done that with having to drill out a pilot screw. It really helps to soak it with penetrating oil but it doesn't always do the trick. Glad to see you got them out. With all the brass plugs still in place to begin with I would have to agree with you that you dropped that spring. The most important part was to have the spare parts with new o rings to reinstall. On the carb that you couldn't count how many turns it was... I would just start at two and a half turns out from lightly seated and go from there. I use the Gunson's Colortune tool to set all my pilot screws. Many on here like it and some hate it. I am sold on it. You obviously will need to plug the intake manifold nipple that the Octy was hooked up to in order for the bike to even start to run right. Gas coming out of your airbox is why I don't get rid of the Octy. Did you verify your float heights when back in the carbs? It is critical that they be set at 23mm from the base of the carb body with the gasket removed to the highest point of the float. That will help to stop the flooding into the airbox. When you notice the gas coming out of the airbox it is very dangerous to start the bike... especially while the carbs are not properly tuned. DAMHIK... but one little backfire can set your bike on fire. While I am tuning a new to me set of carbs I have both a fire extinguisher and a wet towel next to me if the event that occurs. You are getting close. You will need to get the pilot jets set properly and the carbs need to be synched. I am glad to hear that the drill bit tap die worked well for you.

[TheNannerpus]

As cajun31 pointed out, I missed checking the pilot screws in my carb rebuild. So today I took it off again, removed all the rubber parts and got to removing them.

All the parts looked good to my untrained eye, but I replaced everything anyway. This picture shows the old parts.

Two things happened that made the day interesting:

1. I checked the screws' positions before removing, and the #3 screw was all the way in. When I took it out, there was no spring inside!?! I'm convinced I just dropped it somewhere.
2. The #4 screw stripped. I ended up drilling it out, but I drilled off-center and couldn't use my screw extractor! 😬. As I began to panic, I decided to make decisions on how to fix it. If 1 hole got me in this mess, then a 2nd hole might get me out of it. So I drilled a 2nd hole next to the 1st one. Luckily, the two holes merged and created a new slot for me to use a screwdriver again. Luckily, it worked! I did score the edge of the hole a bit, but not enough to matter.

So with that tail-clenching fun behind me, I put the carb back together and reinstalled. I used a hanging gas tank with a splitter to see if removing the octy, plus the carb rework did anything.

After a few cranks, the bike fired up. Eventually, I could take it off choke, and even rev it! It was great to hear the sweet music. Keep in mind, I have yet to even ride this bike, and this was the first time I heard it in real life. I've had to resort to YouTube videos to watch others ride their XS.

I realized I didn't cap the old vacuum nipple, so that is next on the list, along with synching.

Also, it leaked gas as I tried restarting, but once it fired up, it stopped leaking. From what I can tell, it looks like it's leaking from the airbox? Wouldn't that mean the float valves are not working and the bowls are flooding? I replaced all those parts, and checked them, so I'd be surprised if they are the culprit.

Any thoughts?

[TheNannerpus]

wingnut
Your post is borderline prophetic. I worked in this today, read on.

cajun31
Your recommendation using the 1/8" drill and 4mm tap worked flawlessly. Thank you!

[wingnut]

Instead of the 4mm tap just screw a pointy sheet metal screw in the small hole you drilled and grab it with your small vicegrips and pull it out of your way. This way you avoid damaging the heads of the idle mixture screw. Speaking of those, they may be difficult to get out. Soak them in PB blaster and custom grind a screw driver to fit the screw slots. They are soft and you can create a drill it out situation if not careful.

[cajun31]

Three MNS under one roof........ cajun31 you are the man.

---Bax

What can I say... it's an addiction.

[Bax]

Three MNS under one roof........ cajun31 you are the man.

---Bax

[cajun31]

I've NEVER liked the octy! My MNS was the only bike I kept it, the rest, tossed it. My current ride is a '79 Special with a Standard tank. No octy, manual petcocks. When I put the stock tank back on, no octy. Just my personal preference.

You made me chuckle. Maybe that is the reason I like the octy. I own three MNS.

[DiverRay]

I've NEVER liked the octy! My MNS was the only bike I kept it, the rest, tossed it. My current ride is a '79 Special with a Standard tank. No octy, manual petcocks. When I put the stock tank back on, no octy. Just my personal preference.

[cajun31]

To pull the carbs:
1. Remove ALL the bolts holding the airbox on.
2.Loosen all the clamps holding the carbs on.
3. Remove the fuel lines and octy if you are still using it.
4. Remove the breather tube from the airbox and engine.
5. Pull the airbox to the rear of the bike as far as you can.
6. Grab the carbs from both sides, twist the rear down, and lever out the LEFT side of the bike.
7. disconnect the throttle cable.
Reverse order to install.

Ray when you say remove the octy are you telling him to completely remove it? It already clears everything as it sits? I might tell him to take the Octi screw out to free it up a bit ... but complete removal is unecessary. I have never had to completely remove the breather tube to get the carbs on and off. Maybe my tube is too flexible though. Probably a good idea if the tube if fairly stiff though. As for the airbox I agree with Bax, much easier to get on and off with the lower half removed. Also helps to do that so that you can get by without removing the breather hose. As clarification when Ray says to move the airbox as far to the rear as possible, you must first pop all the intake rubbers off the carbs. I do that step by pushing the airbox forward and down in one good strong motion. Then you make sure the metal bracket that holds the airbox in place with a bolt in the frame clears the frame in the same motion. You can then pull the airbox back and out of the way without taking it all the way off the bike. The air snorkel will slide back enough and then you simply rock the carbs out of the intake manifolds and then work the carbs out to the left side of the bike. As Ray stated ... make sure you take the throttle cable loose before trying to take the carbs all the way out.

[2WheelFun]

An Aussie, the barefoot mechanic has an excellent YouTube video on carb removal/install. You may find a tip or two on it.

[Bax]

Just going to add to Ray's procedure. Taking the lower air cleaner off the air box gives a bit more room to move the air box around

---Bax

[DiverRay]

To pull the carbs:
1. Remove ALL the bolts holding the airbox on.
2.Loosen all the clamps holding the carbs on.
3. Remove the fuel lines and octy if you are still using it.
4. Remove the breather tube from the airbox and engine.
5. Pull the airbox to the rear of the bike as far as you can.
6. Grab the carbs from both sides, twist the rear down, and lever out the LEFT side of the bike.
7. disconnect the throttle cable.
Reverse order to install.

[TheNannerpus]

cajun31

Oh man, thanks! I have a new clue to solving this bike's problems. I didn't know about this. I wondered what all the extra parts in the carb rebuild kits were about 😳. Sucks that I have to pull the carb again, but I need the practice.

[cajun31]

I did clean those things out, and they didn't seem all that dirty. But I went through a whole can of chemtool anyways. The outsides were far worse - a product of that leaking octy spraying gas all over, I think. Even the inside of the air box was sooty and greasy. I spent several hours degreasing that bike 😓, not perfection, but definite improvement.

The biggest PITA to me was getting the air inlet boots reattached.

My reinstall process was

1. Install intake manifold boots
2. Try installing airbox
3. Uninstall intake manifold boots
4. Retry installing airbox
5. Install intake manifold boots again
6. Squeeze in carb, attach to manifold boots
7. Fight for well over an hour with attaching those 🤬 air box boots

After all this it started up aaaaand........leaked like crazy from that darn octy, just like before I tore it apart. I have questions on that thing that I'll post separately.

At least it idled."

I was looking at the pictures you posted. Unless you have reinstalled the brass plugs (which I don't think you did) over the pilot screws then you have not yet cleaned the carbs well enough. Those plugs need to be removed so that you can inspect the pilot screw, spring, washer and rubber o ring in each one. The rubber o rings are probably old and crusty and need to be replaced. If you pursue that job what I have found to be the safest way to remove the plugs is to take a 1/8" drill bit and drill through the hole on the plug until the bit just gets through the brass then take a 4mm tap die and screw it into the plug. It will bottom out on the top of the pilot screw. Just keep turning it will also lift that plug straight up out of the pilot screw tunnel with no danger of breaking the tower. Once you have all the plugs removed, before removing the screws, lightly seat each screw one at a time by turning them clockwise until you just feel them seated. Important ... count the number of turns you go to seat each one and write that info down. You will want to set them the same when you reinstall them with new o rings. That will put you back to very close to where you are now and the bike should sitll start and idle correctly. Follow the tips on your other post concerning the OCTI and you will be back in business.

[TheNannerpus]

Congrats on your purchase...be prepared to become an expert on carb cleaning...

I did clean those things out, and they didn't seem all that dirty. But I went through a whole can of chemtool anyways. The outsides were far worse - a product of that leaking octy spraying gas all over, I think. Even the inside of the air box was sooty and greasy. I spent several hours degreasing that bike 😓, not perfection, but definite improvement.

The biggest PITA to me was getting the air inlet boots reattached.

My reinstall process was

1. Install intake manifold boots
2. Try installing airbox
3. Uninstall intake manifold boots
4. Retry installing airbox
5. Install intake manifold boots again
6. Squeeze in carb, attach to manifold boots
7. Fight for well over an hour with attaching those 🤬 air box boots

After all this it started up aaaaand........leaked like crazy from that darn octy, just like before I tore it apart. I have questions on that thing that I'll post separately.

At least it idled.