Running rich

[Getzapped]

here is a pic of the bike not that it matters lol

Dude! That is friggin awesome!

[BLOWCLVL]

Ok so I do not have the shared stack style carbs. Yay. Going to re do the float Heights now.

[motoman]

The needles on 1980 model carbs are not adjustable to my knowledge. Is there a jet kit in there? With that said, do you know what position the clip is in on the needles right now since you indicate they are adjustable? That changes things quite a bit it could be needle positioning is the culprit and not so much jetting.

Hard throttle giving black smoke... Does it bog down when you cwhack the throttle, what does it accelerate decently until it gets to higher RPM where it slows down? Another thing to check is the diaphragms themselves do not have holes. That would slow them lifting and cause rich running.

If those carbs are same as year of bike, and it has clip adjustable metering rods in them......they won't work correctly , period. Primary question pertaining to my initial statement.....are the adjustable mixture screws recessed or outside of carbs. If recessed, the bike has the later carbs(80-82). If exposed outside of carbs, then bike has the early carbs(78-79). The 78-79 carbs have a clip adjustable metering rods. The later(80-82) carbs have non-adjustable metering rods.
So, for beginnings, does bike have the early or later carbs? Lets us know on here, as that determines an array of answers depending on whether early or later carbs that may help the bikes dielemma.

[BLOWCLVL]

There is no jet kit. The needle are adjustable and they were at the middle setting. I just moved them to the top leanest setting and no difference. When I hard accelerate it pulls real hard up till about 5k then power is lost and sputters. The float Heights are now set at 23mm. Diaphragms are in great shape. Waiting on my 100 mains to come in.

[Bonz]

Did you establish whether you have the passageways that need plugs or not? I may have missed something in a post? If they have adjustable needles those needles may not be proper for those carbs as is being said.

However to me, the intake and Custom Exhaust are probably the main contributors to what you are dealing with. Definitely get the smaller Mains and let us know.

[motoman]

There is no jet kit. The needle are adjustable and they were at the middle setting. I just moved them to the top leanest setting and no difference. When I hard accelerate it pulls real hard up till about 5k then power is lost and sputters. The float Heights are now set at 23mm. Diaphragms are in great shape. Waiting on my 100 mains to come in.

You still haven't answered yet as to reference to idle mixture screw type(recessed or outside at top of carb venture). From what little bit you DID refer to(clip adjustable metering rods), guess at this point I'm gonna assume the earlier type carbs. So, with that, 23mm IS incorrect float setting for the earlier carbs., and has your fuel bowl levels way to high. If all else I asked for reference to is true, then those floats, with carb bank upside down need to be raised some 2 1/2 or 3mm. Someone will shim in for that static float level setting for the early carbs as I don't have the early XS11 and can't right off remember that setting for the early carbs.
So, at this point, you seriously need to tell us those idle mixture screws location(recessed or not?).

[motoman]

Did you establish whether you have the passageways that need plugs or not? I may have missed something in a post? If they have adjustable needles those needles may not be proper for those carbs as is being said.

However to me, the intake and Custom Exhaust are probably the main contributors to what you are dealing with. Definitely get the smaller Mains and let us know.

Main contributors at this point are.......what he has failed to tell us.......nuttin' to do with whatever intake and exhaust he's runnin.....your gettin' a bit ahead of yourself there.

[BLOWCLVL]

Did you establish whether you have the passageways that need plugs or not? I may have missed something in a post? If they have adjustable needles those needles may not be proper for those carbs as is being said.

However to me, the intake and Custom Exhaust are probably the main contributors to what you are dealing with. Definitely get the smaller Mains and let us know.

no passageway between the stacks.

[BLOWCLVL]

You still haven't answered yet as to reference to idle mixture screw type(recessed or outside at top of carb venture). From what little bit you DID refer to(clip adjustable metering rods), guess at this point I'm gonna assume the earlier type carbs. So, with that, 23mm IS incorrect float setting for the earlier carbs., and has your fuel bowl levels way to high. If all else I asked for reference to is true, then those floats, with carb bank upside down need to be raised some 2 1/2 or 3mm. Someone will shim in for that static float level setting for the early carbs as I don't have the early XS11 and can't right off remember that setting for the early carbs.
So, at this point, you seriously need to tell us those idle mixture screws location(recessed or not?).

The mixture screw is on the outside of the carb recessed in a small stack and is at 1 turn out. I had the floats set to 26mm already and someone here said that was incorrect and to set them at 23mm. The clip adjusting metering rods were in there when I got the bike. According to Yamaha they are the correct ones. I haven't received my 100 mains yet or my 140 pilots

[BLOWCLVL]

Taken from the service manual and set floats according to this.

[BLOWCLVL]

This is where my mixture screw is located.

[DiverRay]

Did the mixture screw look just like that? I know the plastic cap is probably missing, but the screw and spring are on TOP of the stack, not IN the stack.
If so, you probably need to set it up like a '79 carb, and NOT an '80 carb.

[BLOWCLVL]

Did the mixture screw look just like that? I know the plastic cap is probably missing, but the screw and spring are on TOP of the stack, not IN the stack.
If so, you probably need to set it up like a '79 carb, and NOT an '80 carb.

They are set in the stack a little not right on top.

[DiverRay]

So the top of the adjuster is BELOW the level of the stack?

[BLOWCLVL]

So the top of the adjuster is BELOW the level of the stack?

Yes sir it is.