Motor dying in the middle of traffic :(

[anarchy18]

No, if your bike is dieing at idle, it is not the cold weather. Cold weather will require a longer warm up time with the choke on, but once at opperating temp, it will idle fine if all else is correct. Your carbs are causing the problem. I would make sure that the emulsion tubes are crystal clean, and the jets also. Next, I would set the floats to the higest spec. for your bike. Make "SURE" no fuel mix screw tip is broke off in the carb body, then start at 2 1/4 turns out, that is rich, but you can tune down and will help with warm up in your cold temp's. Sync the carbs with your gauge and the valves I told you about and set your idle at around 1200 RPM. If your carbs are realy clean (especialy the emulsion tubes) and you have good fuel flow to them (ie, no lines going down below the bowl hight then back up). After you have it idleing right you can turn the fuel mix screws in 1/4 turn each, then ride for a while and do it again till the idle drops slightly, then back out 1/8th turn, should be good

Cool Dude! Ill try this right here. But what are emulsion tubes? Fuel lines shouldnt get below the carb bowls? Someone told me that didnt matter. Hmmm And what floatbowl heighth do I need? Do u know? Fuel Mix srew and Pilot screw are they the same thing? Which is where? Tips breaking off inside the carb sounds commen the way you mention it!!!!!!

About my Carbtune Pro i contacted <morgan@carbtune.com> in England and asked them why mine are missing and for $5 and a self addressed envelope they are gonna send me the rest of whats missing in my kit. If not i go the aquarium stuff route

[natemoen]

Cool Dude! Ill try this right here. But what are emulsion tubes?

The emulsion tubes are what the main jet screws into and the needle drops down into. Once you pull the main jet out and the diaphragm and needle out the emulsion tube van be pushed out from the main jet hole and it will pop out into the intake area.

Fuel lines shouldnt get below the carb bowls? Someone told me that didnt matter.

Nope should not matter. The pressure of gravity will keep the fuel flowing into the carbs until the fuel level in the tank and lines drops to the level of the T in between the carbs. It can slow the fuel flow slightly (not much) as the fuel level gets lower though.

Hmmm And what floatbowl heighth do I need? Do u know?

For the American models, might be different for the German one though, it would be 23mm from the float bowl mating surface (gasket removed) to the very top edge of the float without compressing the float.

Fuel Mix srew and Pilot screw are they the same thing? Which is where? Tips breaking off inside the carb sounds commen the way you mention it!!!!!!

It is very common that the tips of the pilot screws (fuel mix, idle screws, same thing) to break off on the early model carbs because the tips of them are pointed. Here in America they changed the screws in '80 and they went to a blunt tipped screw and then the tips didn't break off like the early ones, so it was no longer and issue. These screws are going to be located right in in the center of the front intake bell on the carb. Yours will most likely (since it is German I am not positive) be just in front of all the choke parts on the carb in the center of the intake bell on the top inside a tower that will have a plug covering the top. You need to remove that plug, if you havent ever removed that plug then most likely your carbs are not clean down there either.

About my Carbtune Pro i contacted <morgan@carbtune.com> in England and asked them why mine are missing and for $5 and a self addressed envelope they are gonna send me the rest of whats missing in my kit. If not i go the aquarium stuff route

You will most likely get a 4 inch piece of clear tubing with a very small hole down the middle. what you will do it cut it in 4 equal pieces. Then you will cut something like 4 inches off the end of the black hoses and then shove the little clear pieces into the end of the black hose and then put the short black piece onto the other side of the little clear piece. If that made sense.

[Lonerider62]

Usually when you are experiencing running problems it's because of a problem with fueling or ignition, not that really cold weather can't make starting an issue. After you get the engine warmed up, the problem you are having is doutfully the cool weather. I ride in temps quite a bit lower than 0 C.

[skids]

Don't forget also that the black box need a minimum voltage to fire the plugs (10v?). They can show a "skin charge" but have no real capacity. Roll up to a traffic light and ... nothin! Gel type batteries seem to be even worse for that problem. When they are through, they are through.

[motoman]

Engaging the choke was the first thing I tried and almost choked on gas fumes and my eyes watered etc after that and it didnt really help her stay running any better either.////////Either way....way rich in the pilot circuit, and not necessarily the jets either.

[cywelchjr]

You are so correct Sir, I am a Moron, how could I have missed that, of course the Year matters I only have one year now 1979 I apoligize for being so dumb I will stop trying to help others as it is clear I am stupid

I was just pointing out that he was talking about an 81 which is different and has different carbs than a 79 which I was not sure if you were aware of. I know that some owners of 80+ bikes are not aware of the adjustable needles on the 79 and earlier carbs. I certain did not mean to imply you were a moron as you are clearly an intelligent guy. The whole point of the site is to help each other, cause I don't think any of us knows everything.

[cywelchjr]

Cool Dude! Ill try this right here. But what are emulsion tubes? Fuel lines shouldnt get below the carb bowls? Someone told me that didnt matter. Hmmm And what floatbowl heighth do I need? Do u know? Fuel Mix srew and Pilot screw are they the same thing? Which is where? Tips breaking off inside the carb sounds commen the way you mention it!!!!!!

About my Carbtune Pro i contacted <morgan@carbtune.com> in England and asked them why mine are missing and for $5 and a self addressed envelope they are gonna send me the rest of whats missing in my kit. If not i go the aquarium stuff route

What CAN happen if the fuel lines go below the carb bowls is that sometimes you can get a bubble of air in the line that can cause fuel delivery problems. It does seem to be a rare occurance from what I've seen though. That said, I personally like to run my fuel line from each petcock to the carb set on the other side, it keeps them from getting pinched and makes it easy to do tuneups as it's easy to turn the tank around and put the tank where the seat normally sits facing backwarks. It also tends to make it so they don't go below the carb bowls as well, even though AFAIK it doesn't matter.

[XS1100_OEM4ME]

+1

+1. if it goes below the bowls it makes a "sump" like the sump trap on your sink, it is a place for crap to build up and for air to get traped, it you dont need too, why do it

What CAN happen if the fuel lines go below the carb bowls is that sometimes you can get a bubble of air in the line that can cause fuel delivery problems. It does seem to be a rare occurance from what I've seen though. That said, I personally like to run my fuel line from each petcock to the carb set on the other side, it keeps them from getting pinched and makes it easy to do tuneups as it's easy to turn the tank around and put the tank where the seat normally sits facing backwarks. It also tends to make it so they don't go below the carb bowls as well, even though AFAIK it doesn't matter.

[anarchy18]

What CAN happen if the fuel lines go below the carb bowls is that sometimes you can get a bubble of air in the line that can cause fuel delivery problems. It does seem to be a rare occurance from what I've seen though. That said, I personally like to run my fuel line from each petcock to the carb set on the other side, it keeps them from getting pinched and makes it easy to do tuneups as it's easy to turn the tank around and put the tank where the seat normally sits facing backwarks. It also tends to make it so they don't go below the carb bowls as well, even though AFAIK it doesn't matter.

Thats sounds like a good idea right there, crossing the lines!!! I have had problems with mine getting pinched just cause I've had as little as 1" or 2" of too much hose. Especially with really cheap thin walled fuel line. Curls up real easy

[anarchy18]

Well this might be the reason my honda has a delayed throttle response?

+1. if it goes below the bowls it makes a "sump" like the sump trap on your sink, it is a place for crap to build up and for air to get traped, it you dont need too, why do it

I have a Honda Sabre where I have to run my fuel line from the tank to below the carb float bowls in order to be able to add a inline fuel filter. The petcock itself used to have a fuel filter attached to the top of it which was up inside the gas tank but that broke off and looked better cause you didnt see it like that funky setup I have now.

Theres not much room between the tank and where the fuel lines turn and run under the carbs (maybe like 4 inches) and then up into them.

If I dont put enough hose for the inline fuel filter to hang under the carbs the filter will rest against my motor. That can melt the filter or it will scratch my paint job when i ride. EITHER WAY IT LOOKS FUNKY, I NEED AN ALTERNATIVE!!!

[anarchy18]

The emulsion tubes are what the main jet screws into and the needle drops down into. Once you pull the main jet out and the diaphragm and needle out the emulsion tube van be pushed out from the main jet hole and it will pop out into the intake area.



Nope should not matter. The pressure of gravity will keep the fuel flowing into the carbs until the fuel level in the tank and lines drops to the level of the T in between the carbs. It can slow the fuel flow slightly (not much) as the fuel level gets lower though.



For the American models, might be different for the German one though, it would be 23mm from the float bowl mating surface (gasket removed) to the very top edge of the float without compressing the float.



It is very common that the tips of the pilot screws (fuel mix, idle screws, same thing) to break off on the early model carbs because the tips of them are pointed. Here in America they changed the screws in '80 and they went to a blunt tipped screw and then the tips didn't break off like the early ones, so it was no longer and issue. These screws are going to be located right in in the center of the front intake bell on the carb. Yours will most likely (since it is German I am not positive) be just in front of all the choke parts on the carb in the center of the intake bell on the top inside a tower that will have a plug covering the top. You need to remove that plug, if you havent ever removed that plug then most likely your carbs are not clean down there either.



You will most likely get a 4 inch piece of clear tubing with a very small hole down the middle. what you will do it cut it in 4 equal pieces. Then you will cut something like 4 inches off the end of the black hoses and then shove the little clear pieces into the end of the black hose and then put the short black piece onto the other side of the little clear piece. If that made sense.

Im starting to understand some stuff alittle better THANKS TO YOU GUYS!!! EVERYTIME I COME TO THIS SITE I LEARN SOMETHING NEW!!!

Colortuning, I just heard of it. Is it a must, do I need it, how important is it? Someone told me it dont matter cause it only checks your bike at idle without a load on it. He said its useless and other guys swear on it!!!

WHO THINKS I WILL STILL NEED IT after adjusting the pilot screws and synching the carbs the way I've been taught to do it on here without the colortune?

[natemoen]

Im starting to understand some stuff alittle better THANKS TO YOU GUYS!!! EVERYTIME I COME TO THIS SITE I LEARN SOMETHING NEW!!!

Colortuning, I just heard of it. Is it a must, do I need it, how important is it? Someone told me it dont matter cause it only checks your bike at idle without a load on it. He said its useless and other guys swear on it!!!

WHO THINKS I WILL STILL NEED IT after adjusting the pilot screws and synching the carbs the way I've been taught to do it on here without the colortune?

The colortune is for adjusting your idle screws. If you can set the idle screws by other means then you do not need it.

[bikerphil]

I use a colortune sometimes just to get the mixture screws in the ballpark, then fine tune from there reading the spark plug(s) color. Instead, when you sync the carbs you can adjust the mix screws to obtain the highest vacuum reading. That usually gets them right on target.

[Cobia]

Anarchy,
After reading through this string two things come to mind.
One - Your're running oil which too thick for your temps, and
Two - Since you're apparently starving for fuel at idle, check your tank vent. It's under your tank filler cap. There's a hole in the middle that needs to be clear in order for the tank to "vent" and not cause a vacuum which will prevent the fuel from freeflowing into your carbs. This "starving" typically more evident at higher speeds but it's worth checking. Also, check your plugs to see if they're wet (black and oily) or dry (they look almost unused) they're the best indicator of how much fuel is reaching the cylinders at the different fuel rates.

[anarchy18]

Hey, pulled the plugs they were black and sooty but dry!!! I'll definately check out that vent hole on the tank but I also think its time to pull my carbs and inspect em.